| 摘要 |
Processes, intermediates, and products involved in preparing cyclohexanediones of the formula <IMAGE> are disclosed. An aldehyde of the formula R-CHO is reacted with a ketone type compound of the formula (R1)(R2)C=C=O at a temperature below about 110 DEG C. to give a polymer having the repeating unit -OCH(R)C(R1)(R2)CO]n wherein n ranges from about 2 to about 1,000. The polymer is hydrolyzed with alcoholic or aqueous base to produce a mixture of an unsaturated acid of the formula R-CH=C(R1)-COOH and a hydroxy ester or acid of the formula R-CH(OH)C(R1)(R2)-COOR3, the mixture is then contacted with an esterifying agent to convert the acids to esters. The ester mixture is contacted with a dehydrating agent to convert the hydroxy ester to unsaturated ester of the formula R-CH=C(R1)-COOR3. The unsaturated ester is contacted with a basic catalyst to cyclize it to the cyclic dione ester of the formula <IMAGE> and this ester is then hydrolyzed and decarboxylated to give the product <IMAGE> wherein: R is selected, e.g., from alkylthio, alkythioalkyl, cycloalkyl, alkyl substituted cycloalkyl, alkoxy, alkanoyloxy, alkoxycarbonyl, aryl, substituted aryl, heterocyclic, or substituted heterocyclic, wherein each group or moiety has up to 20 carbons; and R1, R2 and R3 are each selected, e.g., from alkyl or cycloalkyl of up to 20 carbons, and R2 and R3 can also be hydrogen.
|
