The formation of 2-hydroxy-4-hydroxymethyl-3-(indol-3-yl)-cyclopent-2-enone derivatives from ascorbigens

A facile preparation is described of 3-(indol-3-yl)-2-hydroxy-4-hydroxymeth ylcyclopent-2-enone and its N-derivatives in 15-40% yields by the degradati on of ascorbigen or its N-derivatives in a warm solution of L-ascorbic acid through a sequential domino reaction. The same cyclopentenone derivatives were obtained in 30-40% yields by the condensation of (N-alkylindol-3-yl)gl ycolic acids with ascorbic acid. 2,6-Dihydroxy-1-(indol-3-yl)hexa-1,4-diene -3-one and 2-hydroxy-4-hydroxymethyl-5-(indol-3-yl)cyclopent-2-enone were i dentified as intermediates in this reaction. (C) 2001 Elsevier Science Ltd. All rights reserved.