Premium
Synthesis of (+)‐(4 S , 8 R )hyphen;8hyphen;Epi‐ and (−)‐(4 R , 8 S )‐4‐Epi‐β‐bisabolol
Author(s) -
Fráter Georg,
Müller Urs
Publication year - 1989
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19890720405
Subject(s) - chemistry , kinetic resolution , enantioselective synthesis , reagent , stereochemistry , mesylate , combinatorial chemistry , organic chemistry , catalysis
The first total enantioselective synthesis of (+)‐(4 S , 8 R )‐8‐epi‐β‐bisabolol(+)‐ 1 and of (−)‐(4 R , 8 S )‐4‐epi‐β‐bisabolol ((−))− 1 ) is reported. The key step in the synthesis is the kinetic resolution of (±)− 5 by means of the Sharpless epoxidation yielding (−)‐ and (+}− 6 , respectively. Reduction of the epoxides with LiAlH 4 gave the diols (+)‐and(−)− 7 which were transformed into (+)‐ and (−)− 8 , respectively, via the corresponding mesylate. Reaction of these epoxides with the Grignard reagent derived from homoprenylbromide, assisted by Li 2 CuCl 4 , finished the synthesis of the target compounds 1 with high diastereo‐ and enantioselectivity.