Sequential Knoevenagel Condensation/Cyclization for the Synthesis of Indene and Benzofulvene Derivatives
Shoko Yamazaki, Kohtaro Katayama, Zhichao Wang, Yuji Mikata, Tsumoru Morimoto, Akiya Ogawa
Abstract
N and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The reaction of variously substituted aryl derivatives with dimethyl malonate gave indene and benzofulvene derivatives. The reactions of 2-(1-phenylvinyl)benzaldehyde with Meldrum's acid or malononitrile also gave cyclized compounds in the suitable sequential or stepwise conditions. Furthermore, the reaction of 2-arylbenzaldehydes has been investigated. The limitation and scope have been described. The reaction mechanism of the cyclization steps has been examined by DFT calculations.
Topics & Concepts
ChemistryIndeneKnoevenagel condensationPiperidineMalononitrileYield (engineering)Organic chemistryMedicinal chemistryBenzaldehydePyridineMalonateCatalysisMaterials scienceMetallurgyCyclopropane Reaction MechanismsCatalytic C–H Functionalization MethodsAsymmetric Synthesis and Catalysis