| abstract |
PURPOSE: The isoprene unit is introduced in an aldehyde or its acetal using a silyl derivative of isoprene to produce a terpene compound useful as perfume or drug under calm conditions in high yield. n CONSTITUTION: The reaction between 2-silylmethyl-1,3-butadiene derivative of formula I (R 1 WR 3 are alkyl, aryl, aralkyl) and an aldehyde of formula II (R 4 is hydrocarbyl that may be substituted) or its acetal is effected in a solvent as dichloromethane in the presence of a Lewis acid catalyst as TiCl 4 at -100W +100°C and is followed by hydrolysis to give the alcohol of formula III or its ether. The hydrolysis is effected by keeping the reaction mixture to about 0°C, adding ice water and ethyl ether and standing for 1W30min. n COPYRIGHT: (C)1980,JPO&Japio |