Regioselective Synthesis of Heterocycles Containing Nitrogen Neighboring an Aromatic Ring by Reductive Ring Expansion Using Diisobutylaluminum Hydride and Studies on the Reaction Mechanism
作者:Hidetsura Cho、Yusuke Iwama、Kenji Sugimoto、Seiji Mori、Hidetoshi Tokuyama
DOI:10.1021/jo902177p
日期:2010.2.5
including indoline, 1,2,3,4,5,6-hexahydrobenz[b]azocine, 3,4-dihydro-2H-benzo[b][1,4]oxazine, 2,3,4,5-tetrahydrobenzo[b][1,4]thiazepine, 1,2,3,4,5,6-hexahydroazepino[3,2-b]indole, 2,3,4,5-tetrahydro-1H-benzothieno[2,3-b]azepine, 2,3,4,5-tetrahydro-1H-benzothieno[3,2-b]azepine, 5,6-dihydrophenanthridine, and 5,6,11,12-tetrahydrodibenz[b, f]azocine. The reaction mechanism leading to the rearrangement was
描述了与二异丁基氢化铝(DIBALH)稠合到芳环上的环状酮肟的还原扩环反应的系统研究。该反应区域选择性地提供了多种五至八元双环杂环或三环杂环,其包含与芳香环相邻的氮,包括二氢吲哚,1,2,3,4,5,6-六氢苯并[ b ]偶氮辛,3,4-二氢-2 H-苯并[ b ] [1,4]恶嗪,2,3,4,5-四氢苯并[ b ] [1,4]噻氮平,1,2,3,4,5,6-六氢氮庚啶[3 ,2- b ]吲哚,2,3,4,5-四氢-1 H-苯并噻吩并[2,3- b ]氮杂,2,3,4,5-四氢-1 H-苯并噻吩并[3,2- b]氮杂,5,6-二氢菲啶和5,6,11,12-四氢二苯并[ b,f ]偶氮星。基于受限的Becke三参数加Lee-Yang-Parr(B3LYP)密度泛函理论(DFT)和6-31G(d)基础集,研究了导致重排的反应机理。发现该反应通过逐步机理通过三中心过渡态进行,因为沿着本征反应坐标