US4594444A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of sterically hindered hydroxyphenylcarboxylic acid esters
Assignee: BASF Corp
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Filing: 1984-12-12
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Granted: 1986-06-10
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Expires: 2004-12-12
Abstract
Abstract If the transesterification of esters of the formula II ##STR1## with alcohols of the formula III ##STR2## is catalyzed by treatment with catalytic amounts of an oxide or an organo-metallic compound of a metal of the fourth main group or subgroup of the periodic system, and if the resulting melt is then distilled in a flash distillation apparatus under specific conditions, compounds of the formula ##STR3## are obtained in a virtually quantitative yield. In the above formulae, R is methyl or ethyl, A is a radical of an m-hydric aliphatic alcohol, E is methyl or tert-butyl, m is 1 to 4 and n is 0 to 2. The products thus obtained do not contain any interfering by-products and do not have to be additionally purified.
Inventors
- 👤 Ivan Orban
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:46
CPC Classifications
C; C07; C07C; C07C69/00; C07C69/66; C07C69/73; C07C69/732; C07C67/00; C07C67/03; C07C69/76; C07C69/84; C07C69/88
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
165 words
A process for the preparation of compounds of the formula I ##STR13## in which n is the numbers 0 to 2, m is the numbers 1 to 4, A is a radical which is derived from an m-hydric aliphatic alcohol and has 2 to 18 carbon atoms and B is methyl or t.-butyl, by transesterifying approx. m moles of an ester of the formula II ##STR14## in which R is methyl or ethyl, with an alcohol of the formula III ##STR15## which comprises (a) carrying out the transesterification in the presence of an oxide or an organometallic compound of a metal of the fourth main group or fourth subgroup of the periodic system, as catalyst, in an amount between 0.05 and 1.0 mol %, based on the ester of the formula II, and (b) distilling the resulting melt in a flash distillation apparatus under a pressure between 0.5 and 6 mbar, and at a temperature between 230° and 270° C., and granulating the resulting melt.
Claim 2
Dependent Claim
165 words
A process for the preparation of compounds of the formula I ##STR13## in which n is the numbers 0 to 2, m is the numbers 1 to 4, A is a radical which is derived from an m-hydric aliphatic alcohol and has 2 to 18 carbon atoms and B is methyl or t.-butyl, by transesterifying approx. m moles of an ester of the formula II ##STR14## in which R is methyl or ethyl, with an alcohol of the formula III ##STR15## which comprises (a) carrying out the transesterification in the presence of an oxide or an organometallic compound of a metal of the fourth main group or fourth subgroup of the periodic system, as catalyst, in an amount between 0.05 and 1.0 mol %, based on the ester of the formula II, and (b) distilling the resulting melt in a flash distillation apparatus under a pressure between 0.5 and 6 mbar, and at a temperature between 230° and 270° C., and granulating the resulting melt.
Claim 3
Dependent Claim
29 words
A process according to claim 1, wherein the catalyst employed is a tin compound of the formula V ##STR16## in which R 2 is C 4 -C 12 -alkyl.
Claim 4
Dependent Claim
16 words
A process according to claim 2, wherein the compound of the formula V is dibutyltin oxide.
Claim 5
Dependent Claim
83 words
A process according to claim 1 for the preparation of compounds of the formula I by transesterifying an ester of the formula II with an alcohol of the formula III, wherein, in the formulae I, II and III, n is the number 2 and m is the numbers 1, 2 or 4, A is C 2 -C 18 -alkyl if m=1, A is C 2 -C 6 -alkylene, a group ##STR17## if m=2, and A is pentaerythrityl if m=4, and R is methyl.
Claim 6
Dependent Claim
46 words
A process according to claim 1, wherein the catalyst in the transesterification is employed in amounts between 0.1 and 0.3 mol %, based on the ester of the formula II, at temperatures between 110° and 220° C. and under a pressure between 250 and 3 mbar.
Claim 7
Dependent Claim
37 words
A process according to claim 1, wherein the distillation of the melt in the flash distillation apparatus is carried out under a pressure between 1 and 3 mbar and at a temperature between 240° and 260° C.
Claim 8
Dependent Claim
18 words
A process according to claim 1, for the preparation of pentaerythrityl tetrakis-[3-(3,5-di-tert.-butyl-4-hydroxyphenyl)-propionate] by transesterifying methyl 3-(3,5-di-tert.-butyl-4-hydroxyphenyl)-propionate with pentaerythritol.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-09 | 1989-12-09 | 1990-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-09 | 1993-12-09 | 1994-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-09 | 1997-12-09 | 1998-06-10 | $7700.00 | Window Closed / Lapsed |