A Combined Experimental and Theoretical Study of the Polar [3 + 2] Cycloaddition of Electrophilically Activated Carbonyl Ylides with Aldehydes and Imines
作者:Ghenia Bentabed-Ababsa、Aicha Derdour、Thierry Roisnel、Jose A. Sáez、Patricia Pérez、Eduardo Chamorro、Luis R. Domingo、Florence Mongin
DOI:10.1021/jo8027104
日期:2009.3.6
nzylamine) proceed diastereoselectively. The effect of microwave irradiation on the outcome of the reaction was studied. The mechanism of these [3 + 2] cycloaddition reactions has been theoretically investigated using DFT methods. These cycloadditions, which have one-step mechanisms, consist of the nucleophilic attack of the aldehyde oxygen or imine nitrogen on the carbonyl ylide. For the reaction
通过羰基内酯之间的[3 + 2]环加成反应合成了许多2,5-二芳基-1,3-二氧戊环-4,4-二腈和2,4-二苯基-1,3-恶唑烷-5,5-二腈由环氧化物,醛或亚胺生成。与此相反的使用醛类(3,4,5-三甲氧基苯,胡椒醛,1-萘甲醛,吲哚-3-甲醛,呋喃-2-甲醛,和噻吩-2-甲醛)的,反应与亚胺进行(ñ - (苯基亚甲基)甲胺,N-(1,3-苯并二恶唑-5-基亚甲基)丙胺,N-(1,3-苯并二恶唑-5-基亚甲基)丁胺和N-(1,3-苯并二恶唑-5-基亚甲基)苄胺)非对映选择性地进行。研究了微波辐射对反应结果的影响。这些[3 + 2]环加成反应的机理已使用DFT方法进行了理论研究。这些具有一步机制的环加成包括醛氧或亚胺氮对羰基内酯的亲核攻击。对于与醛的反应,在过渡结构处发现了不可预期的反向电荷转移,这归因于背电荷作用。反应性指标的分析表明,羰基乙炔的大亲电特性可诱导它们在这些极性的[3 +