The ionic Diels–Alder reaction of 1-vinyl-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane. Retention of the ortho ester moiety through the use of the trioxabicyclo[2.2.2]octanyl protecting group
作者:Paul G. Gassman、Subhash P. Chavan
DOI:10.1039/c39890000837
日期:——
1-Vinyl-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane adds to 1,3-dienes at low temperatures under Lewis acid catalysis to give Diels–Alder adducts possessing the intact orthoester moiety.
作者:Stewart K. Richardson、Alwarsamy Jeganathan、David S. Watt
DOI:10.1016/s0040-4039(00)96117-3
日期:——
The metalation of (E)-1-(2-chlorovinyl)- or (E)-1-(2-bromovinyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane with tert-butyllithium produced an unsaturated homoenolate anion equivalent which intercepted alkyl halides, aldehydes, ketones, and lactones to afford β-alkylated or β-acylated orthoesters, which, in turn, furnished β-substituted acrylate esters.
Cyclobutane formation in the 2π + 2π cycloaddition of allyl and related cations to unactivated olefins. Evidence for the second step in the proposed mechanism of the ionic diels-alder reaction.
作者:Paul G. Gassman、Andrew C. Lottes
DOI:10.1016/0040-4039(92)88038-7
日期:1992.1
A variety of carbocation activated olefins have been shown to add to unactivated olefins in a 2π + 2π cycloaddition to yield cyclobutanes.
Enantioselective Hydroformylation of 1-Alkenes with Commercial Ph-BPE Ligand
作者:Zhiyong Yu、Meredith S. Eno、Alexandra H. Annis、James P. Morken
DOI:10.1021/acs.orglett.5b01421
日期:2015.7.2
A rhodium complex, in conjunction with commercially available Ph-BPE ligand, catalyzes the branch-selective asymmetric hydroformylation of 1-alkenes and rapidly generates alpha-chiral aldehydes. A wide range of terminal olefins Including 1-dodecene were examined, and all delivered high enantioselectivity (up to 98:2 er) as well as good branch:linear ratios (up to 15:1).