Dimerisations of cinnamates using acidic and acidic/oxidative conditions
作者:Andrew Pelter、Robert S Ward、Reveru Venkateswarlu、Chakicherla Kamakshi、Syed G.A Moinuddin、Pithani V Subhash、Michael B Hursthouse、Simon J Coles、Mark E Light
DOI:10.1016/s0040-4020(01)00742-6
日期:2001.9
It is confirmed that the dimerisation of methyl dialkoxycinnamates in acidic conditions yields trisubstituted indanes. When the reactions are carried out for 1.5 h/0 degreesC in acidic conditions in the presence of DDQ then a variety of lignan types result, two of which represent new classes of lignans. (C) 2001 Elsevier Science Ltd. All rights reserved.
Palladium-Promoted [2 + 2 + 2] Cocyclization of Arynes and Unsymmetrical Conjugated Dienes: Synthesis of Justicidin B and Retrojusticidin B
作者:Ramesh M. Patel、Narshinha P. Argade
DOI:10.1021/ol3028658
日期:2013.1.4
A facile synthesis of natural and unnatural arylnaphthalenes has been demonstrated via the unprecedented palladium-promoted [2 + 2 + 2] cocyclization of arynes and unsymmetrical conjugated dienes using the N-heterocyclic carbene as a ligand. The unsymmetrical dienes used herein are actually α-coupled acrylate–cinnamate combinations bearing two β-positive carbons and follow the key [2 + 2 + 2] cocyclization