Gamma-lactone prodn. from culture broth - by thermal lactonisation of hydroxy acid in broth

摘要

Prodn. of gamma-lactones of formula (I) is effected by (a) heating a culture broth contg. the corresp. hydroxy acid to 60-130 deg. C without adding acid, and (b) extracting (I) in conventional mannner. In (I) R = 4C or 6C alkyl. The broth is heated at 80-120 deg. C for 30-150 (esp. 60-90) min. USE/ADVANTAGE - (I) are useful as flavours and fragrances. The process uses fewer chemicals than prior art processes employing mineral acids for lactonisation (cf.US4560656 and WO8912104), so the prods. should be more acceptable to consumers.