The vinylogous intramolecular Morita-Baylis-Hillman reaction: synthesis of functionalized cyclopentenes and cyclohexenes with trialkylphosphines as nucleophilic catalysts.
The development of the vinylogous intramolecular Morita-Baylis-Hillman reaction for the synthesis of functionalized cyclopentenes and cyclohexenes is described. The reaction involves the trialkyphosphine-catalyzed cyclization of 1,6- or 1,7-diactivated 1,5-hexadienes or 1,6-heptadienes, containing carboxyaldehyde, methyl ketone, or methoxycarbonyl as the olefin activating groups. A representative example of this reaction is the Me(3)P-catalyzed cyclization of 1a in tert-amyl alcohol, which provides the substituted cyclopentene 2a in 95% yield and with 97:3 regioselectivity.
Frank
Scott A
SA
Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA.
Mergott
Dustin J
DJ
Roush
William R
WR
D000478:Alkylation; D002384:Catalysis; D003510:Cyclohexanes / Q000138:chemical synthesis*; D053138:Cyclohexenes; D003517:Cyclopentanes / Q000138:chemical synthesis*; D010720:Phosphines / Q000737:chemistry*
D003510:Cyclohexanes; D053138:Cyclohexenes; D003517:Cyclopentanes; D010720:Phosphines; C052568:cyclohexene