| abstract |
Enantio-selective synthesis of 1'-hydroxybenz-bromoarone of formula (I) by: (a) an enantio-selective cleavage of an ester of formula (II), or (b) a conversion of (II) to a compound of formula (III), followed by enantio-selective reduction. In either case, protected OH groups are deprotected in a final stage. R1 = H, alkyl, alkoxy, OH, hydroxyalkyl or halo; R2 = H or OH protecting group; R3 = alkyl (optionally substituted by alkoxy or OH) or aryl (optionally substituted by alkyl, alkoxy or OH); n = 0-2. Also claimed are the intermediates (III) (IV) (see below) of the preparation. |