ORGANOSILICON COMPOUND AND RUBBER COMPOSITION COMPRISING THE SAME

Abstract

The present invention provides an organosilicon compound that has a novel structure, that makes it possible to obtain a rubber material excellent in mechanical properties, fuel economy, and grip performance, and that is preferably obtained from a naturally occurring material; and a rubber composition comprising the organosilicon compound.

Claims

1. An organosilicon compound represented by the following general formula [A], [B], [1], or [2], or a condensate comprising at least one organosilicon compound selected from organosilicon compounds represented by the following general formulas [A], [B], [1], and [2] as a condensation component: ##STR00025## wherein R.sup.a, R.sup.b, and R.sup.c are each independently any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom, and at least one of Ra, R.sup.b, and RC is any of a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom; R.sup.d is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; L.sup.1 is a single bond or a divalent organic group; R.sup.e, R.sup.f and R.sup.g are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms; and p1 is 0 or 1; ##STR00026## wherein R.sup.h is any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a carboxyl group having 2 to 18 carbon atoms, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, and a halogen atom; R.sup.i and R.sup.j are each independently a substituted or unsubstituted alkylene group having 1 to 8 carbon atoms; W.sup.2 is any of C(O), O, NR.sup.13, and CR.sup.14R.sup.15, and R.sup.13, R.sup.14 and R.sup.15 are a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms or hydrogen; R.sup.k is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; L.sup.2 is a single bond or a divalent organic group; R.sup.l, R.sup.m and R.sup.n are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms; and p2 is 0 or 1; ##STR00027## wherein R.sup.1, R.sup.2, and R.sup.3 are each independently any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom, and at least one of R.sup.1, R.sup.2, and R.sup.3 is any of a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom; R.sup.4 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; R.sup.5 is hydrogen or an organic group; and R.sup.6 is hydrogen or an amino-protecting group; and ##STR00028## wherein R.sup.7 is any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a carboxyl group having 2 to 18 carbon atoms, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, and a halogen atom; R.sup.8 and R.sup.9 are each independently a substituted or unsubstituted alkylene group having 1 to 8 carbon atoms; W.sup.1 is any of C(O), O, NR.sup.13, and CR.sup.14R.sup.15, and R.sup.13, R.sup.14 and R.sup.15 are a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms or hydrogen; R.sup.10 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; R.sup.11 is hydrogen or an organic group; and R.sup.12 is hydrogen or an amino-protecting group.

2. The organosilicon compound according to claim 1, wherein the divalent organic group is a linear linking group having bonds at both ends and optionally having a side chain, and when a distance between the two bonds is counted with the number of atoms, the distance is 10 or less.

3. The organosilicon compound according to claim 2, wherein the linear linking group is one or a combination of two or more selected from a linear alkylene group, NH, and C(O).

4. The organosilicon compound according to claim 2, wherein the side chain is a substituent or a hydrocarbon group optionally having a substituent.

5. The organosilicon compound according to claim 2, wherein the side chain is a natural -amino acid side-chain group or a group derived from a natural -amino acid side-chain group.

6. The organosilicon compound according to claim 1, wherein the monovalent hydrocarbon group having 1 to 10 carbon atoms represents an alkyl group having 1 to 4 carbon atoms or a phenyl group.

7. The organosilicon compound according to claim 1, wherein in the formula [1], R.sup.1, R.sup.2, and R.sup.3 are each independently a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, and R.sup.4 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms.

8. A rubber composition comprising a rubber; a silica filler; and an organosilicon compound represented by the following general formula [A], [B], [1], or [2], or a condensate comprising at least one organosilicon compound selected from organosilicon compounds represented by the following general formulas [A], [B], [1], and [2] as a condensation component; ##STR00029## wherein R.sup.a, R.sup.b, and R.sup.c are each independently any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom, and at least one of R.sup.a, R.sup.b, and R.sup.c is any of a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom; R.sup.d is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; L.sup.1 is a single bond or a divalent organic group; R.sup.e, R.sup.f and R.sup.g are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms; and p1 is 0 or 1; ##STR00030## wherein R.sup.h is any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a carboxyl group having 2 to 18 carbon atoms, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, and a halogen atom; R.sup.i and R.sup.j are each independently a substituted or unsubstituted alkylene group having 1 to 8 carbon atoms; W.sup.2 is any of C(O), O, NR.sup.13, and CR.sup.14R.sup.15, and R.sup.13, R.sup.14 and R.sup.15 are a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms or hydrogen; R.sup.k is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; L.sup.2 is a single bond or a divalent organic group; R.sup.l, R.sup.m and R.sup.n are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms; and p2 is 0 or 1; ##STR00031## wherein R.sup.1, R.sup.2, and R.sup.3 are each independently any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom, and at least one of R.sup.1, R.sup.2, and R.sup.3 is any of a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a hydroxy group, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a carboxyl group having 2 to 18 carbon atoms, and a halogen atom; R.sup.4 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; R.sup.5 is hydrogen or an organic group; and R.sup.6 is hydrogen or an amino-protecting group; and ##STR00032## wherein R.sup.7 is any of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, a siloxy group having a substituted or unsubstituted alkoxy group having 1 to 4 carbon atoms, an aminoalkoxy group having 1 to 18 carbon atoms, an alkylaminoalkoxy group having 2 to 18 carbon atoms, a dialkylaminoalkoxy group having 3 to 18 carbon atoms, a hydroxy group, a carboxyl group having 2 to 18 carbon atoms, a polyalkylene glycol monoalkyl ether group represented by C.sub.aH.sub.2a+1O((CH.sub.2).sub.bO).sub.c wherein a is 1 to 18, b is 1 to 6, and c is 1 to 18, and a halogen atom; R.sup.8 and R.sup.9 are each independently a substituted or unsubstituted alkylene group having 1 to 8 carbon atoms; W.sup.1 is any of C(O), O, NR.sup.13, and CR.sup.14R.sup.15, and R.sup.13, R.sup.14 and R.sup.15 are a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms or hydrogen; R.sup.10 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms and optionally having an aromatic ring; R.sup.11 is hydrogen or an organic group; and R.sup.12 is hydrogen or an amino-protecting group.

9. The rubber composition according to claim 8, wherein the divalent organic group is a linear linking group having bonds at both ends and optionally having a side chain, and when a distance between the two bonds is counted with the number of atoms, the distance is 10 or less.

10. The rubber composition according to claim 9, wherein the linear linking group is one or a combination of two or more selected from a linear alkylene group, NH, and C(O).

11. The rubber composition according to claim 9, wherein the side chain is a substituent or a hydrocarbon group optionally having a substituent.

12. The rubber composition according to claim 9, wherein the side chain is a natural -amino acid side-chain group or a group derived from a natural -amino acid side-chain group.

13. The rubber composition according to claim 8, wherein the monovalent hydrocarbon group having 1 to 10 carbon atoms represents an alkyl group having 1 to 4 carbon atoms or a phenyl group.

14. The rubber composition according to claim 8, wherein in the formula [1], R.sup.1, R.sup.2, and R.sup.3 are each independently a substituted or unsubstituted alkoxy group having 1 to 18 carbon atoms, and R.sup.4 is a substituted or unsubstituted divalent hydrocarbon group having 1 to 18 carbon atoms.

15. The rubber composition according to claim 8, further comprising at least one selected from a vinyl organosilicon compound, an amino organosilicon compound, an alkyl organosilicon compound, an epoxy organosilicon compound, a methacrylic organosilicon compound, a (protected) mercapto organosilicon compound, a (poly)sulfide organosilicon compound, and condensates thereof.

16. The rubber composition according to claim 8, wherein the rubber is one or two or more selected from natural rubber (NR), polyisoprene rubber (IR), styrene-butadiene copolymer rubber (SBR), polybutadiene rubber (BR), acrylonitrile-butadiene copolymer rubber (NBR), chloroprene rubber (CR), ethylene-propylene copolymer rubber (EPDM), and butyl rubber (IIR).

17. The rubber composition according to claim 8, wherein the silica filler is a wet silica having a BET specific surface area of 20 to 300 m.sup.2/g.

18. A rubber material using the rubber composition according to claim 8.

19. A tire, a belt, or an anti-vibration rubber using the rubber material according to claim 18.

Description

EXAMPLES

[0202] Hereinafter, the present invention will be more specifically described with reference to Examples and Comparative Examples. However, the present invention is not limited by the following Examples unless departing from the gist of the present invention, and can also be carried out by appropriately adding modifications within a scope applicable to the gist described above and below, and all such modifications are encompassed within the technical scope of the present invention.

Example 1

Synthesis of Thioester-Type Triethoxysilane Having BOC Alanine Residue (Organosilicon Compound 1)

[0203] Into a 300 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 10.0 g (52.9 mmol) of BOC-alanine (N-(tert-butoxycarbonyl)-L-alanine manufactured by Tokyo Chemical Industry Co., Ltd.), 100 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 12.6 g (52.9 mmol) of 3-mercaptopropyttriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.65 g (5.3 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 12.0 g (58.1 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred for 3 hours. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 17.1 g (yield 79%) of an organosilicon compound 1 represented by the following formula [7], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0204] .sup.1H-NMR (500 MHz, CDCl.sub.3) 5.0-4.9 (m, 1H), 4.4-4.3 (m, 1H), 3.8 (q, J=7.0 Hz, 6H), 2.9 (t, J=7.5 Hz, 2H), 1.8-1.6 (m, 2H), 1.5 (s, 9H), 1.4 (d, J=7.0 Hz, 3H), 1.2 (t, J=7.0 Hz, 9H).

##STR00015##

Example 2

Synthesis of Thioester-Type Triethoxysilane Having BOC-Valine Residue (Organosilicon Compound 3)

[0205] Into a 300 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 10.0 g (46.0 mmol) of BOC-valine (N-(tert-butoxycarbonyl)-L-valine, manufactured by Tokyo Chemical Industry Co., Ltd.), 100 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 11.0 g (46.0 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.56 g (4.6 mmol) of N,N-dimethyl-4-aminopyridine

[0206] Our Ref. F18-118 (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 10.5 g (50.6 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred for 3 hours. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 17.0 g (yield 85%) of an organosilicon compound 3 represented by the following formula [8], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0207] .sup.1H-NMR (400 MHz, CDCl.sub.3) 5.0 (d, J=9.6 Hz, 1H), 4.3 (dd, J=4.8 Hz and 9.6 Hz, 1H), 3.8 (q, J=6.8 Hz, 6H), 2.9 (t, J=7.6 Hz, 2H), 2.3-2.2 (in, 1H), 1.7-1.6 (m, 2H), 1.5 (s, 9H), 1.2 (t, J=6.8 Hz, 9H), 1.0 (d, J=6.8 Hz, 3H), 0.9 (d, J=6.8 Hz, 3H), 0.7-0.6 (m, 2H).

##STR00016##

Example 3

Synthesis of Thioester-Type Triethoxysilane Having BOC-Leucine Residue (Organosilicon Compound 4)

[0208] Into a 500 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 11.3 g (45.3 mmol) of BOC-leucine monohydrate (N-(tert-butoxycarbonyl)-L-leucine monohydrate, manufactured by Tokyo Chemical Industry Co., Ltd.), 113 g of N,N-dimethylformamide (DMF) (manufactured by Wako Pure Chemical Industries, Ltd.), 10.8 g (45.3 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.55 g (-4.5 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 10.3 g (49.9 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred overnight. After the completion of the reaction, the reaction solution was separated by adding 100 g of ethyl acetate and 1.00 g of ultrapure water, and the separated aqueous phase was extracted twice with 100 g of ethyl acetate. The extracted organic phase was washed with ultrapure water and a 15 wt % aqueous sodium chloride solution sequentially, dried with magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 11.0 g (yield 54%) of an organosilicon compound 4 represented by the following formula [9], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0209] .sup.1H-NMR (400 MHz, CDCl.sub.3) 4.8 (d, J=8.4 Hz, 1H), 4.4-4.3 (m., 1H), 3.8 (q, J=6.8 Hz, 6H), 2.9 (t, J=7.2 Hz, 2H), 1.7-1.6 (m, 5H), 1.5 (s, 9H), 1.2 (t, J=6.8 Hz, 9H), 0.9 (d, J=6.4 Hz, OH), 0.7-0.6 (in, 2H).

##STR00017##

Example 4

Synthesis of Thioester-Type Triethoxysilane Flaying BOC-isoleucine Residue (Organosilicon Compound 5)

[0210] Into a 500 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 11.2 g (46.5 mmol) of BOC-isoleucine hemihydrate (N-(tert-butoxycarbonyl)-L-isoleucine hemihydrate, manufactured by Tokyo Chemical Industry Co., Ltd.) 112 g of DMF (manufactured by Wako Pure Chemical Industries, Ltd.), 10.1 g (46.5 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.57 g (4.6 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 10.6 g (51.1 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred overnight. After the completion of the reaction, the reaction solution was separated by adding 100 g of ethyl acetate and 100 g of ultrapure water, and the separated aqueous phase was extracted twice with 100 g of ethyl acetate. The extracted organic phase was washed. with ultrapure water and a 15 wt % aqueous sodium chloride solution sequentially, dried with magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 11.9 g (yield 57%) of an organosilicon compound 5 represented by the following formula [10], which was a colorless transparent liquid, was obtained. The physical property is shown. below.

[0211] .sup.1H-NMR (400 MHz, CDCl.sub.3) 5.0 (d, J=9.2 Hz, 1H), 4.3 (dd, J=4.4 Hz and 9.6 Hz, 1H), 3.8 (q, J=6.8 Hz, 6H), 2.9 (t, J=7.6 Hz, 2H), 2.14.9 (br, 1H), 1.7-1.6 (m, 2H), 1.5 (s, 9H), 1.5-1.3 (m, 1H), 1.2 (t, J=6.8 Hz, 9H), 1.2-1.0 (m, 1H), 0.9 (d, J=6.8 Hz, 3H), 0.9 (t, J=7.2 Hz, 3H), 0.7-0.6 (m, 2H).

##STR00018##

Example 5

Synthesis of Thioester-Type Triethoxysilane Having BOC-Glutamic Acid Residue (Organosilicon Compound 6)

[0212] Into a 500 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 13.0 g (52.6 mmol) of BOC-glutamic acid (N-(tert-butoxycarbonyl)-L-glutamic acid, manufactured by Tokyo Chemical Industry Co., Ltd.), 130 g of DMF (manufactured by Wako Pure Chemical Industries, Ltd.), 25.1 g (105.2 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 1.28 g (10.5 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 23.9 g (115.7 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred overnight. After the completion of the reaction, the reaction solution was separated by adding 300 g of ethyl acetate, 100 g of hexane and 400 g of ultrapure water, and the separated aqueous phase was extracted twice with 200 g of ethyl acetate. The extracted organic phase was washed with ultrapure water and a 15 wt % aqueous sodium chloride solution sequentially, dried with magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 15.6 g (yield 43%) of an organosilicon compound 6 represented by the following formula [11], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0213] .sup.1H-NMR (400 MHz, CDCl.sub.3) 5.0 (d, J=8.8 Hz, 1H), 4.4-4.3 (in, 1H), 3.8 (q, J=6.8 Hz, 12H), 2.9 (t, J=6.8 Hz, 4H), 2.7-2.6 (m, 2H), 2.3-2.2 (m, 1H), 2.0-1.9 (m, 1H), 1.8-1.6 (m, 4H), 1.5 (s, 9H), 1.2 (t, J=6.8 Hz, 18H), 0.8-0.6 (m, 4H).

##STR00019##

Example 6

Synthesis of Thioester-Type Triethoxysilane Having BOC-Methionine Residue (Organosilicon Compound 7)

[0214] Into a 200 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 12.0 g (4.8.1 mmol) of BOC-methionine (N-(tert-butoxycarbonyl)-L-methionine, manufactured by Tokyo Chemical Industry Co., Ltd.), 120 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 11.5 g (48.1 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.59 g (4.8 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 10.9 g (52.9 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred for 4 hours. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 19.6 g (yield 87%) of an organosilicon compound 7 represented by the following formula [12], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0215] .sup.1H NMR (400 MHz, CDCl.sub.3) 5.2 (d, J=8.4 Hz, 1H), 4.5-4.4 (m, 1H), 3.8 (q, J=7.2 Hz, 6H), 2.9 (t, J=7.2 Hz, 2H), 2.6-2.4 (m, 2H), 2.2-2.0 (m, 1H), 2.1 (s, 3H), 1.9-1.8 (in, 1H), 1.7-1.6 (m, 2H), 1.4 (s, 9H), 1.2 (t, J=7.2 Hz, 9H), 0.7-0.6 (m, 2H).

##STR00020##

Example 7

Synthesis of Thioester-Type Triethoxysilane Having BOC-Phenylalanine Residue (Organosilicon Compound 8)

[0216] Into a 300 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 14.0 g (52.8 mmol) of BOC-phenylalanine (N-(tert-butoxycarbonyl)-L-phenylalanine, manufactured by Tokyo Chemical Industry Co., Ltd.), 140 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 12.5 g (52.8 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical industry Co., Ltd.), and 0.64 g (5.3 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 12.0 g (58.0 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred for 4 hours. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 22.7 g (yield 89%) of an organosilicon compound 8 represented by the following formula [13], which was a white solid, was obtained. The physical property is shown below.

[0217] .sup.1H-NMR (400 MHz, CDCl.sub.3) 7.4-7.3 (m, 2H), 7.3-7.2 (m, 1H), 7.2-7.1 (m, 2H), 5.0 (d, J=8.8 Hz, 1H), 4.6 (dd, J=6.8 Hz and 14.0 Hz, 1H), 3.8 (q, J=6.8 Hz, 6H), 3.2 (dd, J=5.5 Hz and 14.0 Hz, 1H), 3.1 (dd, J=7.0 Hz and 14.0 Hz, 1H), 2.9 (t, J=7.2 Hz, 2H), 1.8-1.6 (m, 2H), 1.4 (s, 9H), 1.2 (t, J=6.8 Hz, 9H), 0.8-0.6 (m, 2H).

##STR00021##

Example 8

Synthesis of Thioester-Type Triethoxysilane Having BOC-6-Alanine Residue (Organosilicon Compound 9)

[0218] Into a 300 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 12.0 g (63.4 mmol) of BOC--alanine (N-(tert-butoxycarbonyl)--alanine, manufactured by Tokyo Chemical Industry Co., Ltd.), 120 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 15.1 g (63.4 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 0.77 g (6.3 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 14.4 g (69.8 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred overnight. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=9/1), whereby 24.2 g (yield 93%) of an organosilicon compound 9 represented by the following formula [14], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0219] .sup.1H-NMR (400 MHz, CDCl.sub.3) 4.9 (br, 1H), 3.8 (q, J=7.2 Hz, 6H), 3.5-3.3 (m, 2H). 2.9 (t, J=7.2 Hz, 2H), 2.8 (t, J=6.0 Hz, 2H), 1.7-1.6 (m. 2H), 1.2 (t, J=7.2 Hz, 9H), 0.7-0.6 (m, 2H).

##STR00022##

Example 9

Synthesis of Thioester-Type Triethoxysilane Having BOC-6-Aminohexanoic Acid Residue (Organosilicon Compound 10)

[0220] Into a 1000 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 15.0 g (114.4 mmol) of 6-aminohexanoic acid, 119 g of 1N aqueous sodium hydroxide solution (manufactured by Wako Pure Chemical Industries, Ltd.), and 203 g of tetrahydrofuran (THF) (manufactured by Wako Pure Chemical Industries, Ltd.). While stirring the contents of the flask with the magnetic stirrer, 25.0 g (114.4 mmol) of di-tert-butyl dicarbonate (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the resulting mixture was stirred overnight. After the completion of the reaction, the reaction solution was acidified with hydrochloric acid (manufactured by Wako Pure Chemical Industries, Ltd.), and the resulting solution was extracted twice by adding 200 g of ethyl acetate. The extracted organic phase was washed with ultrapure water and a 15 wt % aqueous sodium chloride solution sequentially, dried with magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain 28.0 g of crude BOC-6-aminohexanoic acid, which was a colorless transparent liquid. The obtained compound was used in the next reaction without purification.

[0221] Into a 500 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 28.0 g of crude BOC-6-aminohexanoic acid, 265 g of dichloromethane (manufactured by Wako Pure Chemical Industries, Ltd.), 27.3 g (114.4 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), and 1.4 g (11.4 mmol) of N,N-dimethyl-4-aminopyridine (manufactured by Wako Pure Chemical Industries, Ltd.). After cooling to 5 C. while stirring the contents of the flask with the magnetic stirrer, 26.0 g (125.8 mmol) of N,N-dicyclohexylcarbodiimide (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto. Then, the resulting mixture was heated to room temperature and stirred for 5 hours. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel. chromatography (n-hexane/ethyl acetate=9/1), whereby 44.4 g (yield in two steps 86%) of an organosilicon compound 10 represented by the following formula [15], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0222] .sup.1H-NMR (400 MHz, CDCl.sub.3) 4.6-4.5 (br, 1H), 3.8 (q, J=6.8 Hz, 6H), 3.1-3.0 (m, 2H), 2.9 (t, J=7.2 Hz, 2H), 2.5 (t, J=7.2 Hz, 2H), 2.7-2.6 (m, 4H), 1.5-1.4 (m, 2H), 1.4 (s, 9H), 1.4-1.3 (m, 2H), 1..2 (t, J=6.8 Hz, 9H), 0.7-0.6 (m, 2H).

##STR00023##

Example 10

Synthesis of Boc Protected 3-Mercaptopropyltriethoxysilane (Organosilicon Compound 11)

[0223] Into a 500 mL three-necked flask equipped with a thermometer and a magnetic stirrer were added 10.0 g (41.9 mmol) of 3-mercaptopropyltriethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), 300 g of acetonitrile (manufactured by Wako Pure Chemical Industries, Ltd.), and 15.1 g (109.1 mmol) of potassium carbonate (manufactured by Wako Pure Chemical Industries, Ltd.). While stirring the contents of the flask with the magnetic stirrer, 11.9 g (54.5 mmol) of di-tert-butyl dicarbonate (manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto, and the resulting mixture was stirred at room temperature for 2 days. After the completion of the reaction, the reaction solution was filtered, and the filtrate was concentrated under reduced pressure. The concentrated residue was purified by silica gel chromatography (n-hexane/ethyl acetate=50/1), whereby 10.7 g (yield 76%) of an organosilicon compound 11 represented by the following formula [16], which was a colorless transparent liquid, was obtained. The physical property is shown below.

[0224] .sup.1H-NMR (400 MHz, CDCl.sub.3) 3.8 (q, J=6.8 Hz, 6H), 2.8 (t, J=7.2 Hz, 2H), 2.8-2.7 (m, 2H), 1.5 (s, 9H), 1.2 (t, J=6.8 Hz, 9H), 0.8-0.7 (m, 2H).

##STR00024##

Examples 11 to 20 and Comparative Example 1

Production of Rubber Composition

[0225] A kneading test was performed using LABO PLASTOMILL 10C100 equipped with 250 cc Banbury mixer type attachment BR-250 (manufactured by Toyo Seiki Co., Ltd.). The apparatus temperature was set to oil circulation heating of 90 C., and the rotor rotation speed of the mixer was kept constant at 60 rpm. The test was performed with a compounding based on 100 g of rubber. The test procedure was as follows. The rubber component was masticated for 30 seconds, the agents shown iii Ingredients (I) of Table 1 were then added, and the resulting mixture was kneaded for 30 seconds. Next, the agents shown in Ingredients (II) of Table 1 were added, the resulting mixture was kneaded for 3 minutes, and then the kneaded product was discharged. Note that the amounts of the organosilicon compounds in Examples and Comparative Examples were adjusted so that the amounts of sulfur in the organosilicon compounds in Examples and Comparative Examples were the same. After cooling the discharged kneaded product with a 6-inch roll of room temperature, the crosslinking components shown in Ingredients (III) of Table 1 were added, and the resulting mixture was kneaded for 6 minutes to obtain a sheet (uncrosslinked sheet) having a thickness of about 2 mm. The next day, the uncrosslinked sheet was subjected to hot press crosslinking at 160 C. for 20 minutes to obtain a test sample (crosslinked sheet).

Tensile Test

[0226] A No. 3 dumbbell-shaped test piece was punched out from the crosslinked sheet and subjected to a tensile test in accordance with JIS K6251 using Technograph TG-2kN manufactured by Minebea.

Dynamic Viscoelasticity Test 1

[0227] A test piece of 4 mm width40 mm length2 mm thickness was punched out from the crosslinked sheet and subjected to a measurement using DMS61.00 manufactured by Seiko Instruments Inc. under the conditions of a distance between chucks of 20 mm, an initial load of 1000 mN, a tensile strain of 10 m, and a vibration of 10 Hz. The measurement temperature range was from 20 C. to 20 C., and the temperature was raised at a rate of 2 C./min to measure a value of tan at 0 C.

Dynamic Viscoelasticity Test 2

[0228] A test piece of 4 mm width25 mm length2 mm thickness was punched out from the crosslinked sheet and subjected to a measurement using Rheogel-4000 manufactured by UBM under the conditions of a distance between chucks of 20 mm, an initial strain of 5%, a dynamic amplitude of 0.5%, and a vibration of 10Hz. The measurement temperature range was kept constant at 60 C.

Abrasion Test

[0229] A test piece (crosslinked sheet) in accordance with JIS K6264 was prepared and subjected to a measurement at a tilt angle of 15 using an Akron abrasion tester in accordance with JIS K6264-2. The applied load was 44.1 N, and the rotation speed of the test piece was 250 rotations per minute.

[0230] The compounding ingredients used in Examples and Comparative Examples are shown below.

[0231] *1 SL552 manufactured by JSR Corporation

[0232] *2 Nipsil AQ (BET specific surface area: 215 m.sup.2/g) manufactured by Tosoh Silica Corporation

[0233] *3 Sunthene 41.5 manufactured by Nippon Oil Corporation

[0234] *4 STEARIC ACID SAKURA manufactured by NOF Corporation

[0235] *5 Nocrac 6C manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.

[0236] *6 CABRUS-2 ((poly)sulfide organosilicon compound) manufactured by Osaka Soda Co., Ltd.

[0237] *7 Zinc Oxide of No.2 manufactured by Sakai Chemical Industry Co., Ltd.

[0238] *8 Nocceler D (guanidine crosslinking accelerator) manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.

[0239] *9 Nocceler CZ (sulfonamide crosslinking accelerator) manufactured by Ouchi Shinko Chemical Industrial Co., Ltd.

[0240] *10 Colloidal sulfur manufactured by Hosoi Chemical Industry Co., Ltd.

TABLE-US-00001 TABLE 1 Unit: parts by mass Example Example Example Example Example Example Example Example Example Example Comparative 11 12 13 14 15 16 17 18 19 20 Example 1 rubber styrene- 100 100 100 100 100 100 100 100 100 100 100 component butadiene rubber *1 Ingredients silica *2 40 40 40 40 40 40 40 40 40 40 40 (I) softening agent *3 20 20 20 20 20 20 20 20 20 20 20 stearic acid *4 2 2 2 2 2 2 2 2 2 2 2 antiaging agent *5 1 1 1 1 1 1 1 1 1 1 1 Ingredients silica *2 40 40 40 40 40 40 40 40 40 40 40 (II) organosilicon 10.7 compound 1 organosilicon 6.4 compound 2 *6 organosilicon 11.4 compound 3 organosilicon 11.8 compound 4 organosilicon 11.8 compound 5 organosilicon 9.0 compound 6 organosilicon 12.3 compound 7 organosilicon 12.7 compound 8 organosilicon 10.7 compound 9 organosilicon 11.8 compound 10 organosilicon 8.8 compound 11 Ingredients zinc oxide *7 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0 (III) accelerator 1 *8 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 accelerator 2 *9 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 1.8 sulfur *10 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5

[0241] The test results of Examples and Comparative Example obtained by the above tests are shown in Table 2.

TABLE-US-00002 TABLE 2 Example Example Example Example Example Example Example Example Example Example Comparative 11 12 13 14 15 16 17 18 19 20 Example 1 Tensile TSb 16.3 17.4 16.6 18.2 17.4 19.5 19.9 18.7 19.0 13.8 16.5 Test (MPa) Eb 285 290 275 290 265 350 340 285 285 250 300 (%) Dynamic 0.359 0.342 0.391 0.299 0.366 0.307 0.325 0.371 0.282 0.387 0.193 Viscoelasticity Test 1 tan at 0 C. Dynamic 0.110 0.108 0.100 0.109 0.100 0.141 0.119 0.107 0.111 0.104 0.168 Viscoelasticity Test 2 tan at 60 C. Abrasion Test 0.26 0.23 0.25 0.21 0.26 0.25 0.19 0.23 0.18 0.24 0.30 (cc/1000 rotations)

[0242] As shown in Table 2, as compared with Comparative Example 1 using the most widely used polysulfide organosilicon compound, each of Examples 11 to 20 using the organosilicon compounds of the present invention had a larger value of tan at 0 C., which suggested that the grip performance was excellent, and had a smaller value of tan at 60 C., which suggested that the fuel economy was excellent. Usually, when the value of tan at 60 C. becomes smaller, the value of tan at 0 C. also tends to become smaller. On the other hand, Examples 11 to 20 using the organosilicon compounds of the present invention are favorable in that those are excellent in both grip performance and fuel economy.

[0243] Furthermore, it was suggested that Examples 11 to 20 using the organosilicon compounds of the present invention are not inferior in mechanical properties and abrasion resistance as compared with Comparative Example 1.

[0244] In addition, the organosilicon compounds of the present invention used in Examples 11 to 17 are favorable in that those are derived from sustainable materials, unlike the polysulfide organosilicon compound, which is currently used widely

INDUSTRIAL APPLICABILITY

[0245] By using the organosilicon compound of the present invention, it is possible to provide a rubber composition and a rubber material that are excellent in grip performance and fuel economy. Therefore, such a rubber composition and such a rubber material can be suitably used for the production of rubber parts to be dynamically used, such as a tire tread, an anti-vibration rubber, and a belt.