Reactive Intermediates from DMDO Oxidation of Ynamides. Trapping of a de novo Chiral Push−Pull Carbene via Cyclopropanation
作者:Ziyad F. Al-Rashid、Richard P. Hsung
DOI:10.1021/ol703083k
日期:2008.2.1
The reaction profile of DMDO oxidations of ynamides is described. This work illustrates the first examples of highly diastereoselective intramolecular cyclopropanations of a push-pull carbene derivedfrom alkyne oxidation. In addition, the ynamide oxidation provides facile access to ketoimides and reveals mechanistic insights into the chemistry of electronically biased oxirenes.
A stereoselective intramolecular cyclopropanation via a de novo class of push–pull carbenes derived from DMDO-epoxidations of chiral ynamides
作者:Hongyan Li、Jennifer E. Antoline、Jin-Haek Yang、Ziyad F. Al-Rashid、Richard P. Hsung
DOI:10.1039/c0nj00063a
日期:——
This work describes the first examples of diastereoselective intramolecular cyclopropanations of a de novo class of pushâpull carbenes derived from DMDO-epoxidations of chiral ynamides. This reaction sequence essentially constitutes a tandem epoxidationâcyclopropanation that effectively gives rise to a series of structurally unique amido-cyclopropanes. A plausible mechanistic model is proposed revealing insights into this novel cyclopropanation process.