Abstract: Epoxides containing hydroxy groups are rearranged enantioselectively using a chiral base to give allyl alcohols in high enantiomeric excess, e.g. ##STR1## If R.sup.3 .noteq.H, the reaction also has the effect of generating a chiral tetrasubstituted carbon atom.

Abstract: A method for prerparing compounds of formula (I), wherein R is an optionally substituted alkenyl or alkynyl radical having up to 8 carbon atoms, or an optionally substituted mono- or polycyclic aryl or heteroaryl radical, and R.sub.1 and R.sub.2 are an alkyl radical having up to 4 carbon atoms. According to the method, a compound of the formula (II), wherein X is a halogen atom, is exposed to an organometallic compound of the formula (III): RZ, wherein R has the same meaning as before and Z is a metal or metal derivative. Alternatively, a compound of formula (II'), wherein Z' is a metal or metal derivative, is exposed to a compound of the formula (III'): RX', wherein X' is a nucleophilic reaction leaving group.