Tetrahedron letters

Coupling of activated esters to gramines in the presence of ethyl propiolate under mild conditions

DT Jones, GD Artman, RM Williams

Index: Jones, David T.; Artman III, Gerald D.; Williams, Robert M. Tetrahedron Letters, 2007 , vol. 48, # 7 p. 1291 - 1294

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Citation Number: 15

Abstract

During the course of the total syntheses of several natural products and potential biomimetic precursor substrates, we have needed to couple functionalized activated esters to gramine derivatives of various indole ring systems. Three literature methods can be used to form the desired carbon–carbon bond. First, heating of gramine 1 to temperatures greater than >120 °C leads to spontaneous formation of 3-methylene-3H-indole (2) via loss of the dimethyl amine ( ...