First isolation of both indolylcarbinols and diindolylalkanes from microwave-assisted acid (clay)-catalysed reaction of indoles with diethyl ketomalonate

Article abstract of DOI:10.3987/COM-04-10200

Indoles (1a-f) react with diethyl ketomalonate on montmorillonite K10 clay under microwave irradiation to furnish expeditiously (1-4 min) the corresponding indol-3′-ylcarbinols (2a-f; 20-45%) and the respective diindolylalkanes (3a-f; 5-35%), which constitute the first direct evidence for the intermediacy of indolylcarbinols in the formation of diindolylalkanes from the acid-catalysed reaction of indoles with aldehydes and ketones.