Claims
- 1. A method of preparing a compound of the formula: ##STR12## where: each A is a [2.2.1] bicyclic group of the formula: ##STR13## or a [3.1.1] bicyclic group of the formula: ##STR14## where R is alike or different and is hydrogen or C.sub.1 to C.sub.4 alkyl, R' is alike or different and is hydrogen or C.sub.1 to C.sub.4 alkyl or R' on adjacent carbon atoms taken together comprise an olefinic bond, and the dashed line indicates either saturation or c-, d- or d-, e- unsaturation;
- each R.sub.1 is C.sub.1 to C.sub.4 alkylene; and
- each n is the integer 0 or 1; comprising condensing an acid of the formula: ##STR15## where A, R.sub.1 and n have their previously defined meanings at a temperature of from 195.degree. to 200.degree. C. for a period of at least two hours, and thereafter increasing the temperature to from 290.degree. to 295.degree. C. for at least three additional hours in the presence of a catalyst selected from the group consisting of iron oxide, polyphosphoric acid, boron trifluoride, alkaline earth oxides, transition metals and thoria aerogel.
- 2. A process according to claim 1 where A is 3,3-dimethylnorborn-2-yl.
- 3. A process according to claim 2 where R is ethylene.
Parent Case Info
This is a division of application Ser. No. 609,772 now U.S. Pat. No. 4,003,934 filed Sept. 2, 1975.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3201453 |
Manning et al |
Aug 1965 |
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3288853 |
Muench et al. |
Nov 1966 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
609772 |
Sep 1975 |
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