Acylnitrilium ion-initiated heteroannulations in alkaloid synthesis. An efficient, stereocontrolled, total synthesis of the Orchidaceae alkaloid (.+-.)-dendrobine
作者:Cheol Hae Lee、Mark Westling、Tom Livinghouse、Andrew C. Williams
DOI:10.1021/ja00037a009
日期:1992.5
A concise total synthesis of (±)-dendrobine is described that proceeds in eight steps from 2-methylcyclopent-2-en-1-one. The key transformation in this approach is the silver ion mediated cyclocondensation of the isonitrile 6 with the acyl chloride 5. This highly convergent reaction proceeds in excellent (88%) overall yield to provide the Δ 1 -pyrroline 4