| abstract |
PURPOSE:To produce the titled compound important in perfumery industry, in one step, by the cyclization dehydration of 3-(2-cyclohexanoyl)propionic acid or its derivative in the presence of a specific noble metal catalyst and a metallic compound cocatalyst. CONSTITUTION:The objective compound can be prepared by cyclizing and dehydrating the 3-(2-cyclohexanoyl)propionic acid of formula I (R1-R6 are H or 1-4C alkyl) or its derivative (e.g. methyl ester) in the presence of preferably 10<-3>-10<-1>mol (based on 1mol of the starting substance) of one or more catalysts selected from Pd, Pt, Rh and Ru, and 10<-2>-5mol (based on 1mol of the above noble metal catalyst) of a cocatalyst selected from groups II-IV and group VIII metal compounds (e.g. oxide, sulfate, nitrate, chloride, acetylacetonate, etc. of Ba, Ca, Al, Ce, Cr, Mo, W, Fe, Co or Ni), at 230-290 deg.C. |