Patent ID: 7057077

Claim:
A method for producing 2-(alkyl)cycloalkenone of formula (2) comprising dehydrating and isomerizing 2-(1-hydroxyalkyl)cycloalkanone of formula (1): wherein n represents an integer of 1 or 2, R 1 and R 2 each represent a hydrogen atom or a straight or branched-chain alkyl group having 1 to 8 carbon(s), or R 1 and R 2 may form together with adjacent carbon atoms a cyclopentane ring or a cyclohexane ring, wherein n, R 1 and R 2 represent the meanings as defined above, wherein dehydration is conducted using an acid catalyst, the reaction proceeding until a conversion ratio of dehydration reaction based on Compound (1) reaches to 20 to 90%, to obtain a mixture containing Compound (1) and 2-(alkylidene) cycloalkanone of formula (3): wherein n, R 1 and R 2 represent the meanings as defined above; and Compound (3) is isomerized while dehydrating remaining Compound (1).