An efficient synthesis of novel tetrahydrochromeno[2,3-b]chromenes
摘要:
A series of novel tetrahydrochromeno[2,3-b]chromenes is synthesized via the acid-catalyzed dimerization reactions of 5-methoxy- or 6-methoxyflavenes. A rational mechanism for the observed rearrangement is proposed. (C) 2010 Elsevier Ltd. All rights reserved.