Platinum-catalyzed intramolecular hydroalkoxylation of gamma- and delta-hydroxy olefins to form cyclic ethers.
Reaction of 2,2-diphenyl-4-penten-1-ol with a catalytic mixture of [PtCl2(H2C=CH2)]2 (1 mol %) and P(4-C6H4CF3)3 (2 mol %) at 70 degrees C for 24 h led to the isolation of 2-methyl-4,4-diphenyltetrahydrofuran in 78% yield. The platinum-catalyzed hydroalkoxylation of gamma-hydroxy olefins tolerated substitution at the alpha, beta, and gamma-carbon atoms and at the internal and cis and trans terminal olefinic positions. Platinum-catalyzed hydroalkoxylation tolerated a number of functional groups including pivaloate and acetate esters, amides, silyl and benzyl ethers, and pendant hydroxyl and olefinic groups. Pt-catalyzed olefin hydroalkylation was also applicable to the formation of fused- and spirobicyclic ethers and was effective for the hydroalkoxylation of delta-hydroxy olefins to form tetrahydropyran derivatives.
P. M. Gross Chemical Laboratory, Duke University, Durham, North Carolina 27708-0346, USA.
Hua
H
Qian
Xiaoqing
X
Han
Ross A
RA
Widenhoefer
D000438:Alcohols / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry*; D000478:Alkylation; D002384:Catalysis; D003500:Cyclization; D004988:Ethers, Cyclic / Q000138:chemical synthesis*; D010984:Platinum / Q000737:chemistry
D000438:Alcohols; D000475:Alkenes; D004988:Ethers, Cyclic; D010984:Platinum