CYCLOHEPTENONE DERIVATIVE AND ITS PRODUCTION, AND PRODUCTION OF CYCLOHEPTOIMIDAZOLE DERIVATIVE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a new compound, a substituted halocycloheptenone useful as an intermediate for the synthesis of medicaments, esp. for the syntheses of cycloheptanoid compounds such as cycloheptoimidazole derivative. SOLUTION: This new compound is expressed by formula I (R1 is H or a lower alkyl; X is Cl or Br) and is e.g. 3-hydroxy-2-chlorocycloheptenone. When reacting a compound of formula II (R2 is a lower alkyl) with dichlorocarbene formed from chloroform or dibromocarbene formed from bromoform in the presence of a base such as potassium t-butoxide and then by treating the resultant compound with an acid without being isolated, the compound of formula I is obtained as a compound of formula III and IV. The compound of formula IV (i.e. 3-alkoxy-2-chlorocycloheptenone or 3-alkoxy-2- bromocycloheptenone) is obtained by reacting the compound of formula III with an alkylating agent (e.g. an alcohol such as methanol, ethanol or the like) in the presence of an acid catalyst to carry out alkylation.