Novel thermolytic transformations of n-benzoyl 2-aza 3-oxa bicyclo(2.2.1)hept-5-ene and n-benzoyl 2-aza 3-oxa bicyclo(2.2.1)heptane
作者:D. Ranganathan、S. Ranganathan、C.B. Rao
DOI:10.1016/s0040-4020(01)92441-x
日期:1981.1
1)heptane (2). Compound 1 thermally fragments by four major pathways, namely, (3,3)-sigmatropic shift, (4 + 2) cycloreversion, N-O rupture and C-N homolysis. The (3,3)-sigmatropic shift provides a novel route to unusual, bicyclic heterocycles. Electron withdrawing aryl groupings tend to promote the (3,3)-sigmatropic shift pathway over others. The (4 + 2)-cycloreversion of 1 leads to nitroso carbonyl
N-苯甲酰基2-氮杂3-氧杂双环(2.2.1)庚烯(1)和N-苯甲酰基2-氮杂3-氧杂双环(2.2.1)庚烷(2)的仔细研究中遇到了新的热解途径。化合物1通过四个主要途径发生热裂解,即(3,3)-σ位移,(4 + 2)环还原,NO断裂和CN均质化。(3,3)-正相移提供了一条通往异常双环杂环的新颖途径。吸电子的芳基倾向于促进(3,3)-σ转移途径。的(4 + 2)-cycloreversion 1导致亚硝基羰基苯和环戊二烯。PhCONO的弱σ键容易发生均质。由NO断裂引起的中间体导致与PG内过氧化物→PGE变化有关的环戊烯酮自由基。该基团与苯甲酰基基团结合生成4-二苯甲酰氨基环戊烯酮,或通过损失氢而转化为烯酰胺,而后者又与环戊二烯进行(4 + 2)-环加成反应,从而生成新的螺环加合物。CN破裂导致苯甲酰苯胺的形成。