PROCESS FOR REDUCING THE CHLORINE CONTENT OF ORGANOTETRAPHOSPHITES

Abstract

Universally usable process for reducing the chlorine content of organotetraphosphites.

Claims

1. Process for reducing the chlorine content in an organotetraphosphite of one of the general formulae I and II: ##STR00013## where R.sup.1, R.sup.2, R.sup.3, R.sup.4 are each independently selected from: H, (C.sub.1-C.sub.12)-alkyl; V and W are each independently selected from: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-heteroalkyl, (C.sub.4-C.sub.20)aryl (C.sub.4-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-(C.sub.4-C.sub.20)-aryl, (C.sub.4-C.sub.20)-aryl-COO(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl-CONH(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl-CON[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.4-C.sub.20)-heteroaryl, (C.sub.4-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-cycloalkyl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl-(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.4-C.sub.20)-aryl, CO(C.sub.4-C.sub.20)-heteroalkyl, (C.sub.4-C.sub.20)-aryl-CO(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl-CO(C.sub.4-C.sub.20)-aryl; X and Y are each independently selected from O and N; where, in the case that X is O, n=1, and, in the case that Y is O, m=1, and, in the case that X is N, n=1 or 2, and, in the case that Y is N, m=1 or 2; Z is selected from: (C.sub.1-C.sub.14)-alkyl-, (C.sub.4-C.sub.20)-aryl-, (C.sub.4-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl-, (C.sub.1-C.sub.14)-heteroalkyl-, (C.sub.4-C.sub.20)-heteroaryl-, CO(C.sub.4-C.sub.14)-heteroaryl-, CO(C.sub.4-C.sub.20)-aryl-, (C.sub.3-C.sub.12)-cycloalkyl-, (C.sub.3-C.sub.12)-heterocycloalkyl-, (C.sub.4-C.sub.20)-aryl-CO(C.sub.4-C.sub.20)-aryl-, (C.sub.1-C.sub.14)-alkyl-O(C.sub.1-C.sub.14)-alkyl-; where the alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl and heteroaryl groups mentioned are optionally mono- or polysubstituted; comprising the following process steps: a) contacting the organotetraphosphite with a solution comprising at least one solvent and at least one base, where the at least one solvent is selected from aromatics, alcohols, acetone, ethyl acetate, acetonitrile and ethers, and where the at least one base is selected from amine bases, alkoxides, pyridine, pyridine derivatives, N-methyl-2-pyrrolidone, triethylamine and triethanolamine, b) adjusting the temperature to a value in the range from 20 C. to +15 C., c) removing the purified organotetraphosphite.

2. Process according to claim 1, wherein the at least one solvent is selected from acetonitrile, ethyl acetate, ethanol, propanol, toluene.

3. Process according to claim 1, wherein the solution with which the organotetraphosphite is contacted in step a) contains, as well as the at least one solvent and the at least one base, also max. 5% water based on the solvent content.

4. Process according to claim 1, wherein the at least one base is selected from triethylamine and dimethylaminobutane.

5. Process according to claim 1, where X and Y are O.

6. Process according to claim 1, where X and Y are N.

7. Process according to claim 1, where V and W are each independently selected from: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl, (C.sub.4-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.4-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-(C.sub.4-C.sub.20)-aryl, (C.sub.4-C.sub.20)-aryl-COO(C.sub.1-C.sub.12)-alkyl.

8. Process according to claim 1, where V and W are, or just one of the substituents V and W is, ##STR00014## where R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9 are independently selected from H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, -phenyl, COO(C.sub.1-C.sub.12)-alkyl.

9. Process according to claim 1, where Z is selected from: ##STR00015## where R.sup.10, R.sup.11, R.sup.12, R.sup.13, R.sup.14, R.sup.15, R.sup.16, R.sup.17 are each independently selected from: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl, -halogen (such as Cl, F, Br, I), COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-CON[(C.sub.1-C.sub.12)-alkyl].sub.2, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, COOH, OH, SO.sub.3H, SO.sub.3Na, NO.sub.2, CN, NH.sub.2, N[(C.sub.1-C.sub.12)-alkyl].sub.2.

10. Process according to claim 1, wherein the organotetraphosphite used in process step a) has a chlorine content of 1500 ppm to 100 000 ppm.

11. Process according to claim 1, wherein the purified organotetraphosphite has a chlorine content of <1000 ppm.

12. Process according to claim 1, where R.sup.1, R.sup.3, R.sup.4 are H.

13. Process according to claim 1, where R.sup.2 is tert-butyl.

14. Process according to claim 1, where the organotetraphosphite has one of the structural formulae III, IV, V, VI, VII, VIII, IX, X, XI, XII, XIII, XIV and XV: ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022##

Description

EXAMPLE 1: SYNTHESIS OF (III)

[0094] To a stirred solution of 6-chlorodibenzo[d,f][1,3,2]dioxaphosphepine (0.548 g; 2.188 mmol) in THF (4 ml) is added dropwise at 0 C. a mixture of Hostanox 03 (ethylenebis[3,3-bis(3-tert-butyl-4-hydroxyphenyl)butyrate]) (0.395 g; 0.497 mmol), triethylamine (0.62 ml) and THF (6 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0095] Purification by column chromatography (hexane/dichloromethane, 1:4, R.sub.f=0.4) gives 0.449 g (0.272 mmol; 54%) of the tetraphosphite (III).

[0096] Analysis (calc. for C.sub.96H.sub.94O.sub.16P.sub.4=1651.68 g/mol): C, 71.41 (71.26) %; H, 5.73 (5.74) %; P, 7.53 (7.50) %.

[0097] .sup.31P-NMR (CD.sub.2Cl.sub.2): 145.4 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.37 (36H); 1.92 (6H); 3.17 (4H); 3.93 (4H); 7.07 . . . 7.59 (44H) ppm.

[0098] ESI-TOF HRMS: m/e 1652.55888 (M+H).sup.+.

EXAMPLE 2: SYNTHESIS OF (IV)

[0099] To a stirred solution of 4,8-di-tert-butyl-6-chloro-2,10-dimethoxydibenzo[d,f][1,3,2]dioxaphosphepine (2.387 g; 5.644 mmol) in THF (12 ml) is added dropwise at 0 C. a mixture of Hostanox 03 (ethylenebis[3,3-bis(3-tert-butyl-4-hydroxyphenyl)butyrate]) (1.019 g; 1.282 mmol), triethylamine (1.6 ml) and THF (12 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h. Purification by column chromatography (hexane/dichloromethane, 1:8, R.sub.f=0.28) gives 1.437 g (0.614 mmol; 48%) of the tetraphosphite (IV).

[0100] Analysis (calc. for C.sub.138H.sub.174O.sub.24P.sub.4=2340.74 g/mol): C, 70.82 (70.81) %; H, 7.57 (7.49) %; P, 5.19 (5.29) %.

[0101] .sup.31P-NMR (CD.sub.2Cl.sub.2): 139.9 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.27 (36H); 1.43 (72H); 1.93 (6H); 3.16 (4H); 3.88 (24H), 3.93 (4H), 6.83 . . . 7.17 (28H) ppm.

[0102] ESI-TOF HRMS: m/e 2341.14642 (M+H).sup.+.

EXAMPLE 3: SYNTHESIS OF (V)

[0103] To a stirred solution of bis(2,4-di-tert-butylphenyl) phosphorochloridite (3.381 g; 7.086 mmol) in THF (15 ml) is added dropwise at 0 C. a mixture of Hostanox 03 (ethylenebis[3,3-bis(3-tert-butyl-4-hydroxyphenyl)butyrate]) (1.280 g; 1.61 mmol), triethylamine (2 ml) and THF (15 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0104] Purification by column chromatography (hexane/dichloromethane, 1:1, R.sub.f=0.57) gives 3.6 g (1.41 mmol; 87%) of the tetraphosphite (V).

[0105] Analysis (calc. for C.sub.162H.sub.230O.sub.16P.sub.4=2557.44 g/mol): C, 76.26 (76.08) %; H, 9.05 (9.06) %; P, 4.93 (4.84) %.

[0106] .sup.31P-NMR (CD.sub.2Cl.sub.2): 130.7 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.37 (72H); 1.39 (36H); 1.47 (72H); 1.91 (6H); 3.16 (4H); 3.92 (4H), 7.00. 7.47 (36H) ppm.

[0107] ESI-TOF HRMS: m/e 518.37751; 647.46192; 1135.27566.

EXAMPLE 3a: ALTERNATIVE SYNTHESIS OF (V)

[0108] In a 250 ml Schlenk flask, 9.2 g (0.044 mol) of 2,4-di-tert-butylphenol were admixed with 140 ml of dried toluene and 7 ml (0.050 mol) of triethylamine.

[0109] In a 500 ml Schlenk flask, 7.2 g (0.005 mol) of the chlorophosphite (10) were dissolved in 110 ml of dried toluene and cooled to 0 C. in an ice bath.

[0110] The 2,4-di-tert-butylphenol/toluene/Et.sub.3N solution was added gradually to the chlorophosphite/toluene solution which had been cooled down to 0 C. beforehand.

[0111] On completion of addition, the mixture was warmed to room temperature gradually and while stirring overnight.

[0112] For workup, the amine hydrochloride obtained was filtered off. The residue obtained was washed with 30 ml of dried toluene. The mother liquor obtained was concentrated to dryness under reduced pressure.

[0113] Yield: 12.5 g

[0114] Chlorine content titration: 0.21/0.21% by weight

EXAMPLE 4: SYNTHESIS OF (VI)

[0115] To a solution of the chlorophosphite (10) (0.441 g; 0.367 mmol) in toluene (5 ml) is added dropwise at 0 C. while stirring a solution of 2-phenylphenol (0.5 g; 2.938 mmol) in a mixture of toluene (7 ml) and triethylamine (3.7 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0116] Purification by column chromatography (dichloromethane, R.sub.f=0.82) gives 0.541 g (0.239 mmol; 65%) of the tetraphosphite (VI).

[0117] Analysis (calc. for C.sub.146H.sub.134O.sub.16P.sub.4=2268.54 g/mol): C, 77.34 (77.30) %; H, 5.98 (5.96) %; P, 5.85 (5.46) %.

[0118] .sup.31P-NMR (CD.sub.2Cl.sub.2): 129.9 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.16 (36H); 1.85 (6H); 3.06 (4H); 3.89 (4H), 6.76 . . . 7.44 (84H) ppm.

[0119] ESI-TOF HRMS: m/e 2290.8538 (M+Na).sup.+.

EXAMPLE 5: SYNTHESIS OF (VII)

[0120] To a solution of the chlorophosphite (10) (0.612 g; 0.511 mmol) in toluene (5 ml) is added dropwise at 0 C. while stirring a solution of 1-naphthol (0.589 g; 4.084 mmol) in a mixture of toluene (12 ml) and triethylamine (5.2 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0121] Purification by column chromatography (dichloromethane, R.sub.f=0.77) gives 0.629 g (0.305 mmol; 60%) of the tetraphosphite (VII).

[0122] Analysis (calc. for C.sub.130H.sub.118O.sub.16P.sub.4=2060.24 g/mol): C, 75.67 (75.79) %; H, 5.99 (5.77) %; P, 6.01 (6.01) %.

[0123] .sup.31P-NMR (CD.sub.2Cl.sub.2): 131.3 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.33 (36H); 1.89 (6H); 3.11 (4H); 3.87 (4H), 6.98 . . . 8.19 (84H) ppm.

[0124] ESI-TOF HRMS: m/e 2082.72565 (M+Na).sup.+.

EXAMPLE 6: SYNTHESIS OF (VIII)

[0125] To a solution of the chlorophosphite (10) (0.612 g; 0.511 mmol) in toluene (5 ml) is added dropwise at 0 C. while stirring a solution of 1-naphthol (0.589 g; 4.084 mmol) in a mixture of toluene (12 ml) and triethylamine (5.2 ml). The mixture is left to stir at room temperature overnight and filtered, the filtrate is concentrated under reduced pressure and the residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0126] Purification by column chromatography (dichloromethane, R.sub.f=0.82) gives 0.57 g (0.277 mmol; 54%) of the tetraphosphite (VIII).

[0127] Analysis (calc. for C.sub.130H.sub.118O.sub.16P.sub.4=2060.24 g/mol): C, 75.47 (75.79) %; H, 5.50 (5.77) %; P, 6.23 (6.01) %.

[0128] .sup.31P-NMR (CD.sub.2Cl.sub.2): 129.5 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.34 (36H); 1.90 (6H); 3.13 (4H); 3.89 (4H), 7.05 . . . 7.87 (84H) ppm.

[0129] ESI-TOF HRMS: m/e 2082.72637 (M+Na).sup.+.

EXAMPLE 7: SYNTHESIS OF (IX)

[0130] To a solution of the chlorophosphite (10) (0.734 g; 0.613 mmol) in toluene (6 ml) is added dropwise at 0 C. while stirring a solution of methyl 4-hydroxybenzoate (0.746 g; 4.901 mmol) in a mixture of toluene (14 ml) and triethylamine (6.2 ml). The mixture is left to stir at room temperature overnight and filtered, and the filtrate is concentrated under reduced pressure.

[0131] The residue obtained is first dried at 50 C./0.1 mbar for 2 h and then taken up in dry boiling acetonitrile (10 ml). Storage of the solution at 23 C. gives 0.847 g (0.399 mmol; 65%) of the tetraphosphite (IX).

[0132] Analysis (calc. for C.sub.114H.sub.118O.sub.32P.sub.4=2124.05 g/mol): C, 64.50 (64.46) %; H, 5.50 (5.60) %; P, 5.85 (5.83) %.

[0133] .sup.31P-NMR (CD.sub.2Cl.sub.2): 128.4 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.29 (36H); 1.88 (6H); 3.13 (4H); 3.89 (4H), 3.91 (24H); 6.87 . . . 8.06 (44H) ppm.

[0134] ESI-TOF HRMS: m/e 2146.64606 (M+Na).sup.+.

EXAMPLE 8: SYNTHESIS OF (X)

[0135] To a solution of the chlorophosphite (10) (0.573 g; 0.478 mmol) in toluene (4 mi) is added dropwise at 0 C. while stirring a solution of 2,6-diphenylphenol (0.942 g; 3.826 mmol) in a mixture of toluene (12 ml) and triethylamine (5.9 ml). The mixture is stirred first at room temperature overnight, then at 70 C. for 4 h and at bath temperature 100 C. for another 2 h. The mixture is filtered and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h.

[0136] Purification by column chromatography (hexane/dichloromethane (1:1), R.sub.f=0.16) gives 0.392 g (0.136 mmol; 28%) of the tetraphosphite (X).

[0137] Analysis (calc. for C.sub.194H.sub.166O.sub.16P.sub.4=2877.32 g/mol): C, 80.81 (80.98) %; H, 5.92 (5.81) %; P, 4.19 (4.31) %.

[0138] .sup.31P-NMR (CD.sub.2Cl.sub.2): 142.4 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.05 (36H); 1.82 (6H); 3.04 (4H); 4.04 (4H); 5.79 . . . 7.64 (116H) ppm.

[0139] ESI-TOF HRMS: m/e 2900.11232 (M+Na).sup.+.

EXAMPLE 9: SYNTHESIS OF (XI)

[0140] To a stirred solution of 2-chloro-4,4,5,5-tetraphenyl-1,3,2-dioxaphospholane (1.074 g; 2.493 mmol) in THF (6 ml) is added dropwise at 0 C. a solution of Hostanox 03 (ethylenebis[3,3-bis(3-tert-butyl-4-hydroxyphenyl)butyrate]) (0.451 g; 0.567 mmol) in triethylamine (0.71 ml) and THF (7 ml). The mixture is stirred first at room temperature overnight, then at 70 C. for 10 h, and filtered, and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h and then crystallized from acetonitrile. Yield: 0.66 g (0.278 mmol; 49%) of 92% product (assessment: P NMR)

[0141] .sup.31P-NMR (CD.sub.2Cl.sub.2): 138.5 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.20 (36H); 1.90 (6H); 3.15 (4H); 3.91 (4H); 6.92 . . . 7.63 (92H) ppm.

[0142] ESI-TOF HRMS: m/e 2393.91863 (M+Na).sup.+.

EXAMPLE 10: SYNTHESIS OF (XII)

[0143] To a stirred solution of R-4-chlorodinaphtho[2,1-d:1,2-f][1,3,2]dioxaphosphepine (1.143 g; 3.259 mmol) in THF (8 ml) is added dropwise at 0 C. a solution of Hostanox 03 (ethylenebis[3,3-bis(3-tert-butyl-4-hydroxyphenyl)butyrate]) (0.589 g; 0.741 mmol) in triethylamine (0.93 ml) and THF (9 ml). The mixture is stirred at room temperature overnight and filtered, and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h. Purification by column chromatography (dichloromethane, R.sub.f=0.71) gives 1.128 g (0.550 mmol; 74%) of the tetraphosphite (XII).

[0144] Analysis (calc. for C.sub.130H.sub.110O.sub.16P.sub.4=2052.15 g/mol): C, 75.90 (76.09) %; H, 5.56 (5.40) %; P, 6.14 (6.04) %.

[0145] .sup.31P-NMR (CD.sub.2Cl.sub.2): 145.6 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.34 (36H); 1.91 (6H); 3.16 (4H); 3.93 (4H); 7.07 . . . 8.08 (60H) ppm.

EXAMPLE 11: SYNTHESIS OF (XIII)

[0146] To a solution of the chlorophosphite (10) (1.121 g; 0.936 mmol) in toluene (7 ml) is added dropwise at 0 C. while stirring a solution of 2-hydroxynicotinic acid (0.506 g; 3.742 mmol) in a mixture of toluene (13 ml) and triethylamine (5.6 ml). The mixture is stirred at room temperature overnight and filtered, and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h and is used as obtained. Yield: 0.67 g (0.458 mmol; 49%).

[0147] Analysis (calc. for C.sub.74H.sub.74N.sub.4O.sub.20P.sub.4=1463.30 g/mol): C, 60.92 (60.74) %; H, 5.02 (5.10) %; P, 8.57 (8.47) %.

[0148] .sup.31P-NMR (CD.sub.2Cl.sub.2): 115.1 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.18 (36H); 1.84 (6H); 3.08 (4H); 3.85 (4H); 7.00 . . . 8.63 (24H) ppm.

EXAMPLE 12: SYNTHESIS OF (XIV)

[0149] To a solution of the chlorophosphite (10) (1.356 g; 1.144 mmol) in toluene (9 ml) is added dropwise at 0 C. while stirring a mixture of 1,8-diaminonaphthalene (0.724 g; 4.577 mmol), toluene (18 ml) and triethylamine (7.1 ml). The mixture is stirred at room temperature overnight and filtered, and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h and is used as obtained. Yield: 0.500 g (0.325 mmol; 28%).

[0150] Analysis (calc. for C.sub.90H.sub.94N.sub.8O.sub.8P.sub.4=1539.68 g/mol): C, 70.46 (70.21) %; H, 6.15 (6.15) %; P, 7.95 (8.05) %.

[0151] .sup.31P-NMR (CD.sub.2Cl.sub.2): 82.2 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.04 (36H); 1.82 (6H); 3.08 (4H); 3.65 (4H); 5.72 (m, 8H); 6.51 . . . 7.25 (36H) ppm.

[0152] ESI-TOF HRMS: m/e 1577.57657 (M+Na).sup.+.

EXAMPLE 13: SYNTHESIS OF (XV)

[0153] To a solution of the chlorophosphite (10) (1.585 g; 1.323 mmol) in toluene (20 ml) is added dropwise at 0 C. while stirring a solution of N-benzylmethylamine (1.282 g; 10.581 mmol) in a mixture of toluene (17 ml) and triethylamine (13.4 ml). The mixture is stirred at room temperature overnight and filtered, and the filtrate is concentrated under reduced pressure. The residue obtained is dried at 50 C./0.1 mbar for 2 h and then stirred with diethyl ether (10 ml). Filtration and concentration of the filtrate under reduced pressure yield the product as a white solid. Yield: 1.62 g (0.863 mmol; 65%).

[0154] Analysis (calc. for C.sub.114H.sub.142N.sub.8O.sub.8P.sub.4=1876.29 g/mol): C, 72.83 (72.97) %; H, 7.65 (7.63) %; N, 6.08 (5.97) %; P, 6.76 (6.60) %.

[0155] .sup.31P-NMR (CD.sub.2Cl.sub.2): 128.9 (s) ppm. .sup.1H-NMR (CD.sub.2Cl.sub.2): 1.47 (36H); 1.97 (6H); 2.68 (d, .sup.3J.sub.HP=6.9 Hz; 24H), 3.21 (4H); 3.97 (4H); 4.23 (dd, .sup.3J.sub.HP=8.5 Hz; .sup.2J.sub.HH=14.7 Hz; 8H); 4.40 (dd, .sup.3J.sub.HP=8.5 Hz; .sup.2J.sub.HH=14.7 Hz; 8H); 7.05 . . . 7.39 (52H) ppm.

INVENTIVE EXAMPLE 14: REDUCTION OF CHLORINE LEVEL IN (V)

a) Removal of Chlorine by Means of Degassed Ethanol+1% Degassed Water+5% Degassed DMAB at 0 C.

[0156] For removal of chlorine, 50 ml of degassed ethanol and 2.5 ml of degassed N,N-dimethylaminobutane were first added to 10 g of the crude ligand (V) having a starting chlorine value of 0.2% by weight while stirring, and the mixture was stirred for 1 h. Thereafter, 0.5 ml of degassed water was added, the mixture was cooled to 0 C. and the suspension was stirred for 2 h. Subsequently, the solids were filtered off, washed twice with 40 ml of cold degassed ethanol, and dried.

[0157] Yield: 8.2 g (82%)

[0158] Chlorine content titration: 230 mg/kg (ppm)

b) Chlorine Removal by Means of Degassed Ethanol+Triethylamine at 0 C.

[0159] For removal of chlorine, 600 ml of degassed ethanol and 0.1 ml of triethylamine were first added to 28.5 g of the crude ligand (V) having a starting chlorine value of 0.2% by weight while stirring. The mixture was stirred for 3 h, then cooled to 0 C. by means of an ice bath and stirred for another 1 h. The solids were filtered off, washed with 50 ml of cooled degassed ethanol and dried.

[0160] Yield: 20.05 g=72%

[0161] Chlorine content (Wickbold): 100 mg/kg (ppm)

c) Chlorine Removal by Means of Degassed Ethanol+Triethylamine at 0 C.

[0162] For removal of chlorine, 600 ml of degassed ethanol and 0.2 ml of triethylamine were first added to 28.5 g of the crude ligand (V) having a starting chlorine value of 0.2% by weight while stirring. The mixture was stirred for 3 h, then cooled to 0 C. by means of an ice bath and stirred for another 1 h. The solids were filtered off, washed with 50 ml of cooled degassed ethanol and dried.

[0163] Yield: 20.05 g=72%

[0164] Chlorine content (Wickbold): 80 mg/kg (ppm)

INVENTIVE EXAMPLE 15: SYNTHESIS OF (V) WITH UNDRIED TOLUENE AS SOLVENT AND SUBSEQUENT REMOVAL OF CHLORINE

[0165] In a 500 ml Schlenk flask, 36.9 g (0.177 mol) of 2,4-di-tert-butylphenol were admixed with 300 ml of degassed undried toluene and 28 ml (0.202 mol) of triethylamine.

[0166] In a 2000 ml Schlenk flask, 28.9 g (0.022 mol) of the chlorophosphite (10) were admixed with 300 ml of degassed toluene and cooled to 0 C. in an ice bath.

[0167] The 2,4-di-tert-butylphenol/toluene/Et.sub.3N solution was added gradually to the chlorophosphite/toluene solution which had been cooled down to 0 C. On completion of addition, the reaction mixture was brought to room temperature while stirring overnight.

[0168] The next morning, the mixture was heated to 40 C. with vigorous stirring for 30 min. The mixture was then stirred at 80 C. for a further 45 minutes.

[0169] After cooling to room temperature, the amine hydrochloride obtained was filtered off. The frit residue obtained was washed with 50 ml of degassed toluene. The mother liquor obtained was collected and concentrated to dryness under reduced pressure in a 2 l Schlenk flask which had been repeatedly evacuated and filled with inert gas.

[0170] For further workup, the residue obtained was pulverized and dried overnight. After drying, 750 ml of degassed ethanol and 1.5 ml of triethylamine were added to the pulverized solid. The mixture was stirred at room temperature overnight and then cooled to 0 C. by means of an ice bath and stirred for another 2 h. The solids were filtered, washed with a little cooled degassed ethanol and dried.

[0171] Yield: 36.31 g (63%)

[0172] Chlorine content: Wickbold: 75 mg/kg (ppm)

COMPARATIVE EXAMPLE 16: REDUCTION OF CHLORINE LEVEL IN (V) WITH PURE WATER

[0173] Alternative Preparation of Compound (V):

[0174] To 43.5 g (0.084 mol) of bis(2,4-di-tert-butylphenyl) phosphorochloridite weighed out in a 1000 ml Schlenk flask were added, while stirring, 180 ml of dried toluene. The solution is cooled to 0 C.

[0175] In a second 500 ml Schlenk flask, 15.1 g (0.019 mol) of Hostanox O3 (ethylenebis[3,3-bis(3-tert-4-hydroxyphenyl)butyrate]) were admixed with 210 ml of dried toluene and 24.78 ml=18 g (0.176 mol) of degassed triethylamine while stirring. This reactant mixture dissolved completely after about 5 minutes. A clear solution was obtained. The solution was subsequently added dropwise while stirring to the chlorophosphite solution which had been cooled to 0 C. The reaction mixture was stirred at room temperature overnight.

[0176] For workup, the amine hydrochloride obtained was filtered off, and the filtrate was concentrated to dryness under reduced pressure and subjected to thorough further drying.

[0177] Crude product result: The NMR spectrum shows about 98% P compound (V), and further minor secondary components.

[0178] Chlorine content: Titration 0.12/0.12% by weight (=1200/1200 mg/kg (ppm))

[0179] Comparative example of chlorine reduction: 10 g of the crude product were weighed out and stirred with 100 ml of degassed water (Chromasolv material) under argon for 30 minutes. Subsequently, the heterogeneous mixture was filtered off, rinsed through three times with 10 ml of water and dried overnight at.

[0180] Yield: 9 g (90%)

[0181] 31P NMR: 88.8% P compound (V), 3.8% P phosphite 1, 0.2% P phosphite, 4.3% P phosphite, 2.4% P PH oxide, 0.3% P phosphite

[0182] Chlorine content: 0.11/0.11% by weight (=1100/1200 mg/kg (ppm))

[0183] The results are summarized once again in Table 1.

TABLE-US-00001 TABLE 1 Chlorine values of the organotetraphosphites purified in accordance with the invention Water Chlorine added* Yield content Solvent Base* [%] [%] [%] [ppm] 14a) Ethanol 5 1 82 230 14b) Ethanol 0.017 72 100 14c) Ethanol 0.033 72 80 15) Ethanol 0.2 63 75 16)** Water 100 90 1100 *Percentages relate to the solvent content **Comparative example

[0184] The above examples show firstly that the process according to the invention can significantly reduce the chlorine content of organotetraphosphites, for example from a starting chlorine content of about 2000 ppm to a final content of <250 ppm or to a final content of 100 ppm.

[0185] As becomes clear from the comparative example (Example 16), the use of pure water as solvent does not lead to the desired result of reducing the chlorine level. Moreover, a comparison of the .sup.31P NMR data from this experiment shows that, when pure water is used, about 10% more secondary components have formed as a result of partial hydrolysis.

[0186] The examples also show that the process according to the invention can also be conducted in the presence of traces of water (cf. Example 14a, in which it was possible to reduce the chlorine content to 230 ppm with a yield of 82%). It is therefore possible to use water-containing solvents in the process as well, and so drying thereof is not necessarily required. Water in the case of phosphites can lead to decompositions and hence to yield losses or to formation of secondary components, as shown by the comparative example. This is not observed here, in the case of use of water-containing solvents (cf. Table 1). This means that it is possible to dispense with an inconvenient and costly drying of the solvents. This makes an industrial scale synthesis more economically viable, since drying of the solvents beforehand is unnecessary and hence synthesis steps can be shortened.