N-Heterocyclic Carbene Catalyzed Reactions of α-Bromo-α,β-unsaturated Aldehydes/α,β-Dibromoaldehydes with 1,3-Dinucleophilic Reagents
作者:Changsheng Yao、Donglin Wang、Jun Lu、Tuanjie Li、Weihui Jiao、Chenxia Yu
DOI:10.1002/chem.201103358
日期:2012.2.13
Carbenes ring true: N‐Heterocyclic carbene (NHC) catalyzed reactions of α‐bromo‐α,β‐unsaturated aldehydes/α,β‐dibromoaldehydes with 1,3‐dinucleophilic reagents, such as 1,3‐dicarbonyl compounds, β‐enamino ketones, and β‐enamino esters through umpolung processes gave functionalized 3,4‐dihydropyranones and 3,4‐dihydropyridinones (see scheme). The availability of the starting materials, lack of external
Carbenes正确:N-杂环卡宾(NHC)催化α-溴代α,β-不饱和醛/α,β-二溴代醛与1,3-二亲核试剂(例如1,3-二羰基化合物,β-烯氨基)的反应通过umpolung工艺获得的酮和β-烯胺酯可得到功能化的3,4-二氢吡喃酮和3,4-二氢吡啶酮(参见方案)。原材料的可用性,缺乏外部氧化剂以及产品的实用性使该策略具有吸引力。