Scandium‐ or hafnium‐catalyzed [6+1] annulation reactions of 2‐cyano‐1‐propargyl‐ and 2‐alkynyl‐1‐cyanomethyl‐indoles with Reformatsky reagent delivered 8‐ and 9‐substituted‐azepino[1,2‐a]indole amines in good to high yields.
Construction of Heterocyclic Compounds by Use of α-Diazophosphonates: New One-Pot Syntheses of Indoles and Isocoumarins
作者:Yoshinori Nakamura、Tatsuzo Ukita
DOI:10.1021/ol025916k
日期:2002.7.1
[GRAPHICS]alpha-Diazophosphonates, which have extremely useful properties from a synthetic point of view, are disclosed as 1,1-ambiphilic one-carbon building blocks for one-pot construction of various heterocyclic compounds. They are easily prepared and have higher stability by the effect of the phosphoryl group than corresponding alpha-diazocarbonyl compounds. Using this synthon, we have developed a novel, mild, and efficient synthetic method of 2,3-disubstituted indoles and 3,4-disubstituted isocoumarins.