Diels-Alder reactions of pyridine o-quinodimethane analogues generated from functionalised o-bis(chloromethyl)pyridines
作者:Peter R. Carly、Steven L. Cappelle、Frans Compernolle、Georges J. Hoornaert
DOI:10.1016/0040-4020(96)00680-1
日期:1996.9
2,3- and 3,4-o-bis(chloromethyl)pyridines 3, produced via cycloaddition of the oxazinones 2 with propargyl chloride and 1,4-dichloro-2-butyne, were used as precursors of various pyridine o-quinodimethane analogues. The 2,3- and 3,4-dimethylenepyridine systems were generated via reductive 1,4-elimination with iodide and trapped in situ with various dienophiles to form the tetrahydroquinoline and -isoquinoline
通过恶唑酮2与炔丙基氯和1,4-二氯-2-丁炔的环加成反应制得的多官能2,3-和3,4-邻-双(氯甲基)吡啶3用作各种吡啶邻-的前体。喹二甲烷类似物。2,3-和3,4-二亚甲基吡啶体系是通过用碘化物进行的1,4-还原消除而产生的,并用各种亲二烯体原位捕获以形成四氢喹啉和-异喹啉型加合物。与与丙烯酸甲酯的反应相反,在3,4-二亚甲基吡啶体系中,富含电子的亲二烯体,即二氢呋喃和乙基乙烯基醚,具有区域特异性的环加成反应。