Synthesis of novel electron-deficient chromone-fused dienes via phosphine catalyzed [4+2] annulation
摘要:
alpha-Chromonyl ketoesters undergo phosphine catalyzed [4+2]-annulation reactions with acetylene carboxylates to yield tricyclic benzopyrones in good yields. Under mild acidic conditions, the tricyclic benzopyrones rearrange to provide highly substituted and electron-poor chromone-fused dienes in good yields. (C) 2011 Elsevier Ltd. All rights reserved.
Synthesis of novel electron-deficient chromone-fused dienes via phosphine catalyzed [4+2] annulation
摘要:
alpha-Chromonyl ketoesters undergo phosphine catalyzed [4+2]-annulation reactions with acetylene carboxylates to yield tricyclic benzopyrones in good yields. Under mild acidic conditions, the tricyclic benzopyrones rearrange to provide highly substituted and electron-poor chromone-fused dienes in good yields. (C) 2011 Elsevier Ltd. All rights reserved.
alpha-Chromonyl ketoesters undergo phosphine catalyzed [4+2]-annulation reactions with acetylene carboxylates to yield tricyclic benzopyrones in good yields. Under mild acidic conditions, the tricyclic benzopyrones rearrange to provide highly substituted and electron-poor chromone-fused dienes in good yields. (C) 2011 Elsevier Ltd. All rights reserved.