Titanium(IV)-promoted Mukaiyama aldol-Prins cyclizations.
[reaction: see text] A new version of the Mukaiyama aldol-Prins (MAP) cyclization has been developed. Unsaturated enol ethers such as 3 were found to couple with aldehydes in the presence of TiBr(4) to give 4-bromotetrahydropyran products. This cascade reaction sequence leads to the formation of two new carbon-carbon bonds, a ring, and three new stereogenic centers. We expect this reaction to be a powerful new tool in synthesis.
Patterson
Brian
B
Department of Chemistry, 516 Rowland Hall, University of California, Irvine, California 92697-2025, USA.
Marumoto
Shinji
S
Rychnovsky
Scott D
SD
D000447:Aldehydes / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry; D003500:Cyclization; D004987:Ethers / Q000737:chemistry*; D004988:Ethers, Cyclic / Q000138:chemical synthesis*; D006842:Hydrocarbons, Brominated / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*
D000447:Aldehydes; D000475:Alkenes; D004987:Ethers; D004988:Ethers, Cyclic; D006842:Hydrocarbons, Brominated; D014025:Titanium