Disubstituted diaryloxybenzoheterodiazole compounds

Abstract

A process for the preparation of a disubstituted diaryloxybenzoheterodiazole compound having general formula (XII): ##STR00001## wherein: Z represents a sulfur atom, an oxygen atom, a selenium atom; or a group NR.sub.6 wherein R.sub.6 is selected from linear or branched C.sub.1-C.sub.20 alkyl groups, or from optionally substituted aryl groups; R.sub.2 and R.sub.3, identical or different, represent a hydrogen atom, provided that R.sub.1 does not represent a hydrogen atom; or R.sub.1, R.sub.2 and R.sub.3 are selected from linear or branched C.sub.1-C.sub.20 alkyl groups optionally containing heteroatoms, optionally substituted cycloalkyl groups, optionally substituted aryl groups, optionally substituted, linear or branched C.sub.1-C.sub.20 alkoxy groups, optionally substituted phenoxy groups, or a cyano group; or R.sub.1 and R.sub.2, may optionally be bound together so as to form, together with carbon atoms to which R.sub.1 and R.sub.2 are bound, a saturated, unsaturated, or aromatic, cyclic or a polycyclic system containing from 3 to 14 carbon atoms, optionally containing one or more heteroatoms selected from oxygen, sulfur, nitrogen, silicon, phosphorus, or selenium; or R.sub.2 and R.sub.3 may optionally be bound together so as to form, together with carbon atoms to which R.sub.2 and R.sub.3 are bound, a saturated, unsaturated, or aromatic, cyclic or a polycyclic system containing from 3 to 14 carbon atoms, saturated, unsaturated, or aromatic, optionally containing one or more heteroatoms selected from oxygen, sulfur, nitrogen, silicon, phosphorus, or selenium; wherein R.sub.a and R.sub.b, which are different, represent a hydrogen atom; or are selected from linear or branched C.sub.1-C.sub.20 alkyl groups optionally containing heteroatoms, optionally substituted cycloalkyl groups, optionally substituted aryl groups, optionally substituted linear or branched C.sub.1-C.sub.20 alkoxy groups, optionally substituted phenoxy groups, —COOR.sub.c groups wherein R.sub.c is selected from linear or branched C.sub.1-C.sub.20 alkyl groups, —CON(R.sub.c).sub.2, wherein R.sub.c has the same meanings described above, or —N(R.sub.c).sub.2 groups wherein R.sub.c has the same meanings described above.

Claims

1. A process for the preparation of a disubstituted diaryloxybenzoheterodiazole compound having general formula (XII): ##STR00051## wherein: Z represents a sulfur atom, an oxygen atom, a selenium atom; or a group NR.sub.6 wherein R.sub.6 is selected from linear or branched C.sub.1-C.sub.20 alkyl groups, or from optionally substituted aryl groups; R.sub.2 and R.sub.3, identical or different, represent a hydrogen atom, provided that R.sub.1 does not represent a hydrogen atom; or R.sub.1, R.sub.2 and R.sub.3 are selected from linear or branched C.sub.1-C.sub.20 alkyl groups optionally containing heteroatoms, optionally substituted cycloalkyl groups, optionally substituted aryl groups, optionally substituted, linear or branched C.sub.1-C.sub.20 alkoxy groups, optionally substituted phenoxy groups, or a cyano group; or R.sub.1 and R.sub.2, may optionally be bound together so as to form, together with carbon atoms to which R.sub.1 and R.sub.2 are bound, a saturated, unsaturated, or aromatic, cyclic or a polycyclic system containing from 3 to 14 carbon atoms, optionally containing one or more heteroatoms selected from oxygen, sulfur, nitrogen, silicon, phosphorus, or selenium; or R.sub.2 and R.sub.3 may optionally be bound together so as to form, together with carbon atoms to which R.sub.2 and R.sub.3 are bound, a saturated, unsaturated, or aromatic, cyclic or a polycyclic system containing from 3 to 14 carbon atoms, saturated, unsaturated, or aromatic, optionally containing one or more heteroatoms selected from oxygen, sulfur, nitrogen, silicon, phosphorus, or selenium; wherein R.sub.a and R.sub.b, which are different, represent a hydrogen atom; or are selected from linear or branched C.sub.1-C.sub.20 alkyl groups optionally containing heteroatoms, optionally substituted cycloalkyl groups, optionally substituted aryl groups, optionally substituted linear or branched C.sub.1-C.sub.20 alkoxy groups, optionally substituted phenoxy groups, —COOR.sub.c groups wherein R.sub.c is selected from linear or branched C.sub.1-C.sub.20 alkyl groups, —CON(R.sub.c).sub.2 wherein R.sub.c has the same meanings described above, or —N(R.sub.c).sub.2 groups wherein R.sub.c has the same meanings described above, comprising: (a′.sub.1) causing at least one fluorinated disubstituted diaryloxybenzoheterodiazole compound having general formula (IV): ##STR00052## wherein Z, R.sub.2 and R.sub.3 have the same meanings described above, to react with at least one substituted phenol having general formula (XIII): ##STR00053## wherein R.sub.b has the same meanings described above, said fluorinated disubstituted diaryloxybenzoheterodiazole compound having general formula (IV) and said substituted phenol having general formula (XIII) being used in equal molar ratios, obtaining a reaction mixture comprising at least one disubstituted fluorinated monoaryloxybenzoheterodiazole compound having general formula (XIIa): ##STR00054## wherein Z, R.sub.2, R.sub.3 and R.sub.b have the same meanings described above; (b′.sub.1) adding directly to the reaction mixture obtained in step (a′.sub.1) at least one substituted phenol having general formula (XIV), said substituted phenol having general formula (XIV) being used in equal molar ratios or in molar excess with respect to said fluorinated disubstituted diaryloxybenzoheterodiazole compound having general formula (IV): ##STR00055## wherein R.sub.a has the same meanings described above, obtaining a disubstituted diaryloxybenzoheterodiazole compound having general formula (XV): ##STR00056## wherein Z, R.sub.2, R.sub.3, R.sub.a and R.sub.b have the same meanings described above; (c′.sub.1) causing at least one disubstituted diaryloxybenzoheterodiazole compound having general formula (XV) obtained in the step (b′.sub.1) to react with at least one compound selected from N-haloimides selected from N-bromosuccinimide, N-bromophthalimide, N-iodosuccinimide, and N-iodophthalimide, obtaining a disubstituted halogenated diaryloxybenzoheterodiazole compound having general formula (XVI): ##STR00057## wherein Z, R.sub.2, R.sub.3, R.sub.a and R.sub.b have the same meanings described above, and X is a halogen atom selected from bromine or iodine; (d′.sub.1) causing at least one disubstituted halogenated diaryloxybenzoheterodiazole compound having general formula (XVI) obtained in the step (c′.sub.1) to react with at least one aryl-boron compound having general formula (VIII): ##STR00058## wherein R.sub.1 has the same meanings described above, provided that the R.sub.1 substituent does not represent a hydrogen atom, and the R.sub.7 substituents represent a hydrogen atom, or are selected from linear or branched C.sub.1-C.sub.10 alkyl groups, or from optionally substituted cycloalkyl groups, or the two R.sub.7 substituents may optionally be bound together so as to form, together with other atoms to which the two R.sub.7 substituents are bound, a cyclic compound.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the graph for the value of the power (P) generated expressed in mW (shown as the ordinate) as a function of the distance (d) from the edge to which the photovoltaic cell was attached, expressed in cm (shown as the abscissa).

(2) FIG. 2 shows the value of the power (P) generated expressed in mW (shown as the ordinate) obtained (the example number is shown as the abscissa).

(3) For a better understanding of the present invention and in order to put it into practice, a number of illustrative and non-limiting examples are described below.

(4) 4,7-di-(thien-2′-yl)-2,1,3-benzothiadiazole (DTB) was obtained as described in Example 1 of international patent application WO 2012/007834 in the name of Applicant, the contents of which are incorporated herein as a reference.

EXAMPLE 1

Synthesis of methyl 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoate having formula (IIa)

(5) ##STR00036##

(6) Methyl 4-hydroxybenzoate (Aldrich) (453 mg; 3 mmoles) and potassium carbonate (Aldrich) (1 g; 7.2 mmoles) were added to a suspension of 5,6-difluoro-4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (Sunatech) (1 g; 3 mmoles) in N,N-dimethylformamide (Aldrich) (12 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere: the reaction mixture obtained was heated to 100° C. and held at said temperature, under stirring, for 5 hours, at the end of which phenol (Aldrich) (564 mg; 6 mmoles) was added and the whole was held under stirring, at 92° C., for 12 hours. Subsequently, after cooling to ambient temperature (25° C.), distilled water (30 ml) was added to the reaction mixture obtained and the whole was extracted with dichloromethane (Aldrich) (3×50 ml), The organic phase obtained was washed to neutral with distilled water (3×25 ml) and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: in a gradient from n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9/1 (v/v) to n-heptane (Aldrich)/dichloromethane (Aldrich)/ethyl acetate (Aldrich) in a ratio of 8/1.5/0.5 (v/v/v)], obtaining 1.5 g of methyl 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoate having formula (IIa) (yield=92%).

EXAMPLE 2

Synthesis of methyl 4-{6-[4-(methoxycarbonyl)phenoxy]4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate, having formula (IIb)

(7) ##STR00037##

(8) Methyl 4-hydroxybenzoate (Aldrich) (882 mg; 5.8 mmoles) and potassium carbonate (Aldrich) (952 mg; 6.9 mmoles) were added to a suspension of 5,6-difluoro-4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (Sunatech) (928 mg; 2.8 mmoles) in N,N-dimethylformamide (Aldrich) (12 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere: the reaction mixture obtained was heated to 92° C. and held at said temperature, under stirring, for 12 hours. Subsequently, after the addition of 20 ml of distilled water, there was obtained a precipitate which was recovered by filtration and washed with distilled water (30 ml) obtaining 1.6 g of methyl 4-{6-[4-(methoxycarbonyl)phenoxy]-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIb) (yield=95%).

EXAMPLE 3

Synthesis of methyl 4-[4,7-bis(5-bromo(2-thienyl))-6-phenoxybenzo[3,4-c]1,2,5-thiadazo-5-yloxy]benzoate having formula (a)

(9) ##STR00038##

(10) N-bromosuccinimide (Aldrich) (566.4 mg; 3.2 mmoles) was added to a suspension of methyl 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoate having formula (IIa) obtained as described in Example 1 (800 mg; 1.5 mmoles) in tetrahydrofuran (Aldrich) (8.3 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere, the reaction mixture obtained was left in the dark, under stirring, at ambient temperature (25° C.) for 12 hours. Subsequently, after the addition of 20 ml of distilled water, a precipitate was obtained which was recovered by filtration and washed with distilled water (30 ml), obtaining 945 mg of methyl 4-[4,7-bis(5-bromo(2-thienyl))-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy]benzoate having formula (a) (yield=90%).

EXAMPLE 4

Synthesis of methyl 4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxy benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIc)

(11) ##STR00039##

(12) 2,5-dimethylphenylboronic acid (Aldrich) (510 mg; 3.4 mmoles) and a 2.17 M aqueous solution of potassium carbonate (Aldrich) (1.4 g in 4.8 ml of water; 10.4 mmoles) were added to a solution of methyl 4-[4,7-bis(5-bromo(2-thienyl))-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy]benzoate (a) obtained as described in Example 3 (900 mg; 1.3 mmoles) in 1,4-dioxane (Aldrich) (30 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. After the air present had been removed by means of three vacuum/nitrogen cycles, palladium-tetrakistriphenylphosphine (Aldrich) (75.0 mg; 0.065 mmoles) was added, obtaining a reaction mixture which was heated to 95° C. and held at said temperature, under stirring, for 14 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (3×25 ml). The organic phase obtained was washed to neutral with distilled water (3×25 ml), and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: n-heptane (Aldrich)/dichloromethane (Aldrich) mixture in a ratio of 9/1 (v/v)], obtaining 828.7 mg of methyl-4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxy benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIc) (yield=85%).

EXAMPLE 5

Synthesis of methyl 4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-phenoxy benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IId)

(13) ##STR00040##

(14) 2,6-dimethylphenylboronic add (Aldrich) (510 mg; 3.4 mmoles) and a 2.17 M aqueous solution of potassium carbonate (Aldrich) (1.4 g in 4.8 ml of water; 10.4 mmoles) were added to a solution of methyl 4-[4,7-bis(5-bromo(2-thienyl))-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy]benzoate obtained as described in Example 3 (900.0 mg; 1.3 mmoles) in 1,4-dioxane (Aldrich) (30 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. After the air present had been removed by means of three vacuum/nitrogen cycles, palladium-tetrakistriphenylphosphine (Aldrich) (75.0 mg; 0.065 mmoles) was added, obtaining a reaction mixture which was heated to 95° C. and held at said temperature, under stirring, for 14 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (3×25 ml). The organic phase obtained was washed to neutral with distilled water (3×25 ml), and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: n-heptane (Aldrich)/dichloromethane (Aldrich) mixture in a ratio of 9/1 (v/v)], obtaining 828.7 mg of methyl-4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-phenoxy benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IId) (yield=85%).

EXAMPLE 6

Synthesis of methyl 4-{4,7-bis(5-bromo(2-thienyl))-6-[4-(methoxycarbonyl) phenoxy]-benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (b)

(15) ##STR00041##

(16) N-bromosuccinimide (Aldrich) (478 mg; 2.7 mmoles) was added to a suspension of methyl 4-{6-[4-(methoxycarbonyl)phenoxy]-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate obtained as described in Example 2 (720 mg; 1.2 mmoles) in tetrahydrofuran (Aldrich) (18 ml) in a 100 ml flask equipped with a magnetic stirrer, under an inert atmosphere: the reaction mixture obtained was left in the dark, under stirring, at ambient temperature (25° C.), for 12 hours. Subsequently, after the addition of 20 ml of distilled water, there was obtained a precipitate which was recovered by filtration and washed with distilled water (30 ml), obtaining 773 mg of methyl 4-{4,7-bis(5-bromo(2-thienyl))-6-[4-(methoxycarbonyl)phenoxy]benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (b) (yield=85%).

EXAMPLE 7

Synthesis of methyl 4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-4-(methoxy carbonyl)phenoxylbenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIe)

(17) ##STR00042##

(18) 2,6-di-methylphenylboronic acid (Aldrich) (373.7 mg; 2.5 mmoles) and a 2.1 M aqueous solution of potassium carbonate (Aldrich) (1 g; 7.2 mmoles) were added to a solution of methyl 4-(4,7-bis(5-bromo(2-thienyl))-6-[4-(methoxycarbonyl)phenoxy]benzo[3,4-c]1,2,5-thiadiazo-5-yloxyl-benzoate obtained as described in Example 6 (700 mg; 0.92 mmoles) in 1,4-dioxane (Aldrich) (20 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. After the air present had been removed by means of three vacuum/nitrogen cycles, palladium tetrakis(triphenylphosphine) (Aldrich) (47.9 mg; 0.041 mmoles) was added, obtaining a reaction mixture which was heated to 85° C. and held at said temperature, under stirring, for 14 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (3×25 ml). The organic phase obtained was washed to neutral with distilled water (3×25 ml), and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: n-heptane (Aldrich)/dichloromethane (Aldrich) mixture in a ratio of 9/1 (v/v)], obtaining 594.7 mg of methyl 4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-[4-(methoxy carbonyl)phenoxy]benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIe) (yield=80%).

EXAMPLE 8

Synthesis of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy) benzoic acid having formula (c)

(19) ##STR00043##

(20) Sodium hydroxide (Aldrich) (1.1 g; 28.0 mmoles) was added to a suspension of methyl 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoate haying formula (IIa) obtained as described in Example 1 (1.5 g; 2.8 mmoles) in ethanol (Aldrich) (50 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. The reaction mixture was heated to 80° C. and held at said temperature, under stirring, for 5 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (50 ml). The aqueous phase obtained was acidified to pH 1 through the addition of a 0.1M solution of hydrochloric acid (Aldrich) and extracted with dichloromethane (3×50 ml). The organic phase obtained was washed with brine and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure obtaining 1.4 g of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoic acid having formula (c) (yield=95%),

EXAMPLE 9

Synthesis of 2-[4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)phenylcarbonyloxy]ethyl-2-methylprop-2-enoate having formula (Ia)

(21) ##STR00044##

(22) 2-hydroxyethyl methacrylate (HEMA) (Aldrich) (370.5 mg; 2.85 mmoles) and 4-(N,N-dimethylamino)pyridine (46.4 mg; 0.38 mmoles) were added to a suspension of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoic acid obtained as described in Example 8 (501.6 mg; 0.95 mmoles) in anhydrous dichloromethane (Aldrich) (17 ml) in a 100 ml flask equipped with a magnetic stirrer, under an inert atmosphere. A 0.35 M solution of 1-ethyl-[3-(3-dimethylamino)propyl]carbodiimide hydrochloride (WSC) (Aldrich) in anhydrous dichloromethane [236.7 mg; 1.2 mmoles in 3.4 ml of anhydrous dichloromethane (Aldrich)] was added dropwise to the suspension so obtained, at 0° C., under stirring, over 30 minutes. After 15 minutes, under stirring, at said temperature, the reaction mixture was heated to 20° C. and left at said temperature, under stirring, for 12 hours. Subsequently, the reaction mixture was poured into water (25 ml) and extracted with dichloromethane (Aldrich) (3×50 ml). The organic phase obtained was washed to neutral first with a 0.1 M aqueous solution of hydrochloric acid (Aldrich) (20 ml), then with a saturated aqueous solution of sodium bicarbonate (Aldrich) (30 ml) and finally with brine, and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a neutral alumina column [eluent in a gradient from n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9/1 (v/v) to n-heptane (Aldrich)/dichloromethane (Aldrich)/ethyl acetate (Aldrich) in a ratio of 8.5/1/0.5 (v/v/v)], obtaining 500 mg of 2-[4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)phenylcarbonyloxy]ethyl-2-methyl-prop-2-enoate having formula (Ia) (yield=82%).

EXAMPLE 10

Synthesis of 4-[6-(4-carboxyphenoxy)-4,7-di(2-thienyl)benzo[c],1,2,5-thiadiazo-5-yloxy]benzoic acid having formula (d)

(23) ##STR00045##

(24) Sodium hydroxide (Aldrich) (2 g; 50 mmoles) was added to a suspension of methyl 4-(6-[4-(methoxycarbonyl)phenoxy]-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzoate having formula (IIb) obtained as described in Example 2 (1.5 g; 2.5 mmoles) in ethanol (Aldrich) (83 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. The reaction mixture was heated to 80° C. and held at said temperature, under stirring, for 5 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (1×50 ml). The aqueous phase obtained was acidified to pH 1 through the addition of a 0.1 M solution of hydrochloric acid (Aldrich) and extracted with dichloromethane (3×50 ml). The organic phase obtained was washed with brine and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure obtaining 1.3 g of 4-[6-(4-carboxyphenoxy)-4,7-di(2-thienyl)benzo[c]1,2,5-thiadiaza-5-yloxy]benzoic acid having formula (d) (yield=91%).

EXAMPLE 11

Synthesis of 2-{4-[6-(4-([2-(2-methylprop-2-enoyloxy)ethyl]oxycarbonyl}phenoxy)-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy]phenyl carbonyloxy}ethyl 2-methyl-prop-2-enoate having formula (Ib)

(25) ##STR00046##

(26) 2-hydroxyethyl methacrylate (HEMA) (Aldrich) (741 mg; 5.7 mmoles) and 4-(N,N-dimethylamino)pyridine (92.7 mg; 0.76 mmoles) were added to a suspension of 4-[6-(4-carboxyphenoxy)-4,7-di(2-thienyl)benzo[c]1,2,5-thiadiazo-5-yloxy]benzoic acid obtained as described in Example 8 (543.4 mg; 0.95 mmoles) in anhydrous dichloromethane (Aldrich) (34 ml) in a 100 ml flask equipped with a magnetic stirrer, under an inert atmosphere. A 0.32 M solution of 1-ethyl-[3-(3-dimethylamino)propyl]-carbodiimide hydrochloride (WSC) (Aldrich) in anhydrous dichloromethane [473.5 mg; 2.5 mmoles in 7.8 ml of anhydrous dichloromethane (Aldrich)] was added dropwise to the suspension so obtained, at 0° C., under stirring, over 30 minutes. After 15 minutes under stirring at said temperature, the reaction mixture was heated to 20° C. and left at said temperature, under stirring, for 12 hours. Subsequently, the reaction mixture was poured into water (50 ml) and extracted with dichloromethane (Aldrich) (3×50 ml). The organic phase obtained was washed to neutral first with a 0.1 M aqueous solution of hydrochloric acid (Aldrich) (30 ml), then with a saturated aqueous solution of sodium bicarbonate (Aldrich) (40 ml) and finally with brine, and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a neutral alumina column [eluent n-heptane (Aldrich)/dichloromethane (Aldrich)/ethyl acetate (Aldrich) in a ratio of 8/1/1 (v/v/v)], obtaining 541.3 mg of 2-{4-[6-(4-{[2-(2-methylprop-2-enoyloxy)ethyl]oxycarbonyl}phenoxy)-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy]phenylcarbonyloxy}ethyl 2-methylprop-2-enoate (having formula (Ib) (yield=72%).

EXAMPLE 12

Synthesis of 4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoic acid having formula (e)

(27) ##STR00047##

(28) Sodium hydroxide (Aldrich) (440 mg; 11 mmoles) was added to a suspension of methyl 4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate (6) obtained as described in Example 5 (825 mg; 1.1 mmoles) in ethanol (Aldrich) (25 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere. The reaction mixture was heated to 80° C. and held at said temperature, under stirring, for 5 hours. Subsequently, the reaction mixture was poured into distilled water (50 ml) and extracted with dichloromethane (Aldrich) (1×50 ml). The aqueous phase obtained was acidified to pH 1 through the addition of a 0.1M solution of hydrochloric acid (Aldrich) and extracted with dichloromethane (3×50 ml). The organic phase obtained was washed with brine and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure obtaining 730 mg of 4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoic acid having formula (e) (yield=90%).

EXAMPLE 13

Synthesis of 2-(4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}phenylcarbonyloxy)ethyl-2-methylprop-2-enoate having formula (Ic)

(29) ##STR00048##

(30) 2-hydroxyethyl methacrylate (HEMA) (Aldrich) (370 mg; 2.85 mmoles) and 4-(N,N-dimethylamino)pyridine (46.4 mg; 0.38 mmoles) were added to a suspension of 4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoic acid obtained as described in Example 12 (700 mg; 0.95 mmoles) in anhydrous dichloromethane (Aldrich) (17 ml) in a 100 ml flask equipped with a magnetic stirrer, under an inert atmosphere. A 0.35 M solution of 1-ethyl-[3-(3-dimethylamino)propyl]-carbodiimide hydrochloride (WSC) (Aldrich) in anhydrous dichloromethane [236.7 mg; 1.2 mmoles in 3.4 ml of anhydrous dichloromethane (Aldrich)] was added dropwise to the suspension so obtained, at 0° C., under stirring, over 30 minutes. After 15 minutes under stirring at said temperature, the reaction mixture was heated to 20° C. and left at said temperature, under stirring, for 12 hours. Subsequently, the reaction mixture was poured into water (25 ml) and extracted with dichloromethane (Aldrich) (3×50 ml). The organic phase obtained was washed to neutral first with a 0.1 M aqueous solution of hydrochloric acid (Aldrich) (20 ml), then with a saturated aqueous solution of sodium bicarbonate (Aldrich) (30 ml) and finally with brine, and subsequently dried on sodium sulfate. Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a neutral alumina column [eluent in a gradient from n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9/1 (v/v) to n-heptane (Aldrich)/dichloromethane (Aldrich)/ethyl acetate (Aldrich) in a ratio of 8.5/1/0.5 (v/v/v)], obtaining 644 mg of 2-(4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}phenylcarbonyloxy) ethyl-2-methylprop-2-enoate having formula (Ic) (yield=80%).

EXAMPLE 14

Synthesis of 5-(4-methoxyphenoxy)-6-phenoxy-4,7-di(2-thienyl)benzo[c]1,2,5-thiadiazole having formula (XIIIa)

(31) ##STR00049##

(32) 4-methoxyphenol (Aldrich) (314 mg; 2.5 mmoles) and potassium carbonate (Aldrich) (873 mg; 6.3 mmoles) were added to a suspension of 5,6-difluoro-4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (Sunatech) (851 mg; 2.5 mmoles) in N,N-dimethylformamide (Aldrich) (9 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere: the reaction mixture obtained was heated to 95° C. and held at said temperature, under stirring, for 4 hours, at the end of which there was added phenol (Aldrich) (387 mg; 4.1 mmoles) and the whole was held under stirring, at 92° C., for 12 hours. Subsequently, after cooling to ambient temperature (25° C.), distilled water (30 ml) was added to the reaction mixture obtained and the whole was extracted with dlchloromethane (Aldrich) (3×50 ml). The organic phase obtained was washed to neutral with distilled water (3×25 ml) and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: in a gradient from n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9.5/0.5 (v/v) to n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9/1 (v/v)], obtaining 1.2 g of methyl 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy) benzoate having formula (XIIIa) (yield=93%).

EXAMPLE 15

Synthesis of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy) benzenecarbonitrile having formula (XIIIb)

(33) ##STR00050##

(34) 4-hydroxybenzonitrile (Aldrich) (143 mg; 1.2 mmoles) and potassium carbonate (Aldrich) (414 mg; 3 mmoles) were added to a suspension of 5,6-difluoro-4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (Sunatech) (400 mg; 1.2 mmoles) in N,N-dimethylformamide (Aldrich) (5 ml) in a 100 ml flask equipped with a magnetic stirrer, thermometer and condenser, under an inert atmosphere; the reaction mixture obtained was heated to 100° C. and held at said temperature, under stirring, for 5 hours, at the end of which phenol (Aldrich) (188 mg; 2 mmoles) was added and the whole was held under stirring, at 92° C., for 12 hours. Subsequently, after cooling to ambient temperature (25° C.), distilled water (30 ml) was added to the reaction mixture obtained and the whole was extracted with dichloromethane (Aldrich) (3×50 ml). The organic phase obtained was washed to neutral with distilled water (3×25 ml) and subsequently dried on sodium sulfate (Aldrich). Residual solvent was removed by distillation under reduced pressure. The residue obtained was purified by elution on a silica gel chromatography column [eluent: in a gradient from n-heptane (Aldrich)/dichloromethane (Aldrich) in a ratio of 9/1 (v/v) to n-heptane (Aldrich)/dichloromethane (Aldrich)/ethyl acetate in a ratio of 8/1.5/0.5 (v/v/v)], obtaining 560 mg of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy)benzenecarbonitrile having formula (XIIIb) (yield=92%).

EXAMPLE 16 (Comparative)

(35) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 49.5 mg of 4,7-di-(thien-2″-yl)-2,1,3-benzothiadiazole (DTB), were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was subsequently deposited uniformly on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of a yellow color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(36) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(37) The main surface of the polymer sheet [that coated with the thin film containing 4,7-di-(thien-2′-yl)-2,1,3-benzothiadiazole (DTB)] was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(38) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(39) It will be seen that, in the absence of edge effects, the mean power generated was 5.69 mW (FIG. 1).

EXAMPLE 17

(40) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 107.8 mg of methyl 4-{6-[4-(methoxycarbonyl)phenoxy]-4,7-di(2-thienyl) benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIb) obtained as described in Example 2, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of a red color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(41) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet

(42) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured.

(43) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(44) It will be seen that, in the absence of edge effects, the mean power generated was 7.25 mW (FIG. 1).

EXAMPLE 18

(45) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 92.6 mg of 5-(4-methoxyphenoxy)-6-phenoxy-4,7-di(2-thienyl)benzo[c]1,2,5-thiadiazole having formula (XIIIa) obtained as described in Example 14, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of a red color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(46) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 as then applied to one of the edges of the polymer sheet.

(47) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(48) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(49) It will be seen that, in the absence of edge effects, the mean power generated was 3.21 mW (FIG. 1).

EXAMPLE 19

(50) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 91.7 mg of 4-(6-phenoxy-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy) benzenecarbonitrile having formula (XIIIb) obtained as described in Example 15, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(51) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(52) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured.

(53) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(54) It will be seen that, in the absence of edge effects, the mean power generated was 6.99 mW (FIG. 1).

EXAMPLE 20

(55) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 135.2 mg of methyl 4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-phenoxy benzo[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IId) obtained as described in Example 5, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(56) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(57) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(58) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(59) It will be seen that, in the absence of edge effects, the mean power generated was 12.19 mW (FIG. 1).

EXAMPLE 21

(60) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 145.6 mg of 4-{4,7-bis[5-(2,6-dimethylphenyl)(2-thienyl)]-6-[4-(methoxy carbonyl) phenoxy]benzo-[3,4-c]1,2,5-thiadiazo-5-yloxy}benzoate having formula (IIe) obtained as described in Example 7, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm. An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(61) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(62) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(63) It will be seen that, in the absence of edge effects, the mean power generated was 11.23 mW (FIG. 1).

EXAMPLE 22

(64) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 115.3 mg of 2-[4-(6-phenoxy-4,7-6(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy) phenylcarbonyl-oxy]ethyl 2-methylprop-2-enoate having formula (Ia) obtained as described in Example 9, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(65) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(66) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(67) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(68) It will be seen that, in the absence of edge effects, the mean power generated was 8.29 mW (FIG. 1).

EXAMPLE 23

(69) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 143.4 mg of 2-{4-[6-(4-{[2-(2-methylprop-2-enoyloxy)ethyl]oxycarbonyl}phenoxy)-4,7-di(2-thienyl)benzo[3,4-c]1,2,5-thiadiazo-5-yloxy]phenylcarbonyl oxy}ethyl 2-methylprop-2-enoate having formula (Ib) obtained as described in Example 11, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm.

(70) An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(71) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(72) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(73) It will be seen that, in the absence of edge effects, the mean power generated was 9.13 mW (FIG. 1).

EXAMPLE 24

(74) 6 g of Altuglas VSUVT 100 polymethyl methacrylate (PMMA) and 152.8 g of 2-(4-{4,7-bis[5-(2,5-dimethylphenyl)(2-thienyl)]-6-phenoxybenzo[3,4-c]1,2,5-thiadiazo-5-yloxy}phenylcarbonyloxy)ethyl-2-methylprop-2-enoate having formula (Ic) obtained as described in Example 13, were dissolved in 30 ml of 1,2-dichlorobenzene (Aldrich). The solution obtained was then uniformly deposited on a sheet of polymethyl methacrylate (dimensions 300 mm×90 mm×6 mm) using a film-forming device of the “Doctor Blade” type and the solvent was allowed to evaporate off at ambient temperature (25° C.), in a gentle flow of air, for 24 hours. From this there resulted a transparent sheet of orange color imparted by the film, the thickness of which was ranging from 100 μm to 50 μm. An IXYS-KXOB22-12 photovoltaic cell having a surface area of 1.2 cm.sup.2 was then applied to one of the edges of the polymer sheet.

(75) The main surface of the polymer sheet (that coated with the thin film) was then illuminated with a light source of power 1 sun (1000 W/m.sup.2) and the electrical power generated through the effect of the illumination was measured

(76) The power (P) measurements have been realized by illuminating a portion of sheet of dimensions 100 mm×90 mm, at an increasing distance (d) from the edge to which the photovoltaic cell was attached. These measurements at a variable distance from the photovoltaic cell allow the quantification of the contribution of wave guide, edge and autoabsorption effects.

(77) It will be seen that, in the absence of edge effects, the mean power generated was 14.67 mW (FIG. 1).