Treatment of an alpha,beta-unsaturated ketimine with an alpha,beta-unsaturated carbonyl compound in the presence of a rhenium complex, Re2(CO)10, gave a cyclopentadienyl-rhenium complex. This reaction proceeds via rhenium-catalyzed C-H bond activation of an olefinic C-H bond, insertion of an alpha,beta-unsaturated carbonyl compound into a Re-C bond of the alkenylrhenium intermediate, intramolecular
Proton Donor Acidity Controls Selectivity in Nonaromatic Nitrogen Heterocycle Synthesis
作者:Simon Duttwyler、Shuming Chen、Michael K. Takase、Kenneth B. Wiberg、Robert G. Bergman、Jonathan A. Ellman
DOI:10.1126/science.1230704
日期:2013.2.8
intermediate to a diverse array of compounds sought in pharmaceutical research. Piperidines are prevalent in natural products and pharmaceutical agents and are important synthetic targets for drug discovery and development. We report on a methodology that provides highly substituted piperidine derivatives with regiochemistry selectivelytunable by varying the strength of acid used in the reaction. Readily available
Highly Diastereoselective Synthesis of Tetrahydropyridines by a C–H Activation–Cyclization–Reduction Cascade
作者:Simon Duttwyler、Colin Lu、Arnold L. Rheingold、Robert G. Bergman、Jonathan A. Ellman
DOI:10.1021/ja2119833
日期:2012.3.7
A versatile reaction cascade leading to highly substituted 1,2,3,6-tetrahydropyridines has been developed. It comprises rhodium(I)-catalyzed C-H activation-alkyne coupling followed by electrocyclization and subsequent acid/borohydride-promoted reduction. This one-pot procedure affords the target compounds in up to 95% yield with >95% diastereomeric purity.