Catalytic asymmetric cyclocarbonylation of o-isopropenylphenols: enantioselective synthesis of six-membered ring lactones.
Cyclocarbonylation of o-isopropenylphenols with CO (500 psi) and H(2) (100 psi), using Pd(OAc)(2) and (+)-DIOP as the chiral catalyst, in CH(2)Cl(2) affords 3,4-dihydro-4-methylcoumarins in 60-85% yield and in up to 90% enantiomeric excess. The stereoselectivity is influenced by the structure of the chiral phosphine ligands and substrates, as well as by the reaction conditions.
Dong
Chune
C
Centre for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, Canada K1N 6N5.
Alper
Howard
H
D002248:Carbon Monoxide / Q000737:chemistry; D002384:Catalysis; D003500:Cyclization; D006859:Hydrogen / Q000737:chemistry; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D008024:Ligands; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry; D010636:Phenols / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D007783:Lactones; D008024:Ligands; D010636:Phenols; D010165:Palladium; D002248:Carbon Monoxide; D006859:Hydrogen