3-Boronoacrolein as an exceptional heterodiene in the highly enantio- and diastereoselective Cr(III)-catalyzed three-component [4+2]/allylboration.
This Communication reports the optimization of the first catalytic enantio- and diastereoselective hetero[4+2]/allylboration reaction to provide efficient access to alpha-hydroxyalkyl pyran derivatives. The key substrate 3-boronoacrolein pinacolate appears to be an exceptionally favorable heterodiene for use in Jacobsen's enantioselective reverse electron demand hetero[4+2] reaction with enol ethers, catalyzed by the tridentate (Schiff base)chromium complex 1. This one-pot three-component reaction was successfully applied to a concise total synthesis of (5R,6S)-6-acetoxy-5-hexadecanolide (2), the oviposition attractant pheromone of the female Culex mosquito capable of transmitting the West Nile virus.
Gao
Xuri
X
Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.
Hall
Dennis G
DG
D000171:Acrolein / Q000031:analogs & derivatives*; D000498:Allyl Compounds / Q000737:chemistry*; D001896:Boron Compounds / Q000737:chemistry*; D002384:Catalysis; D002857:Chromium / Q000737:chemistry; D003500:Cyclization; D011714:Pyrans / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000498:Allyl Compounds; D001896:Boron Compounds; D011714:Pyrans; D002857:Chromium; D000171:Acrolein