Nonconcerted Cycloaddition of 2H-Azirines to Acylketenes: A Route to N-Bridgehead Heterocycles

作者：Khlebnikov Alexander F^*; Novikov Mikhail S; Pakalnis Viktoriia V; Yufit Dmitry S

来源：Journal of Organic Chemistry, 2011, 76(22): 9344-9352.

DOI：10.1021/jo201563b

Reactions of acylketenes, generated from diazo diketones, with 2-unsubstituted and 2-monosubstituted 3-aryl-2H-azirines lead to 1:1 or 2:1 adducts, which are derivatives of 5-oxa-1-azabicyclo[4.1.0]hept-3-ene or 5,7-dioxa-1-azabicyclo[4.4.1]undeca-3,8-diene. According to DFT B3LYP/6-31G(d) computations, the formation of (4+2)-monoadducts proceeds via a stepwise non-pericyclic mechanism. Reaction with methanol transforms quantitatively both 1:1 and 2:1 adducts into 1,4-oxazepine derivatives.

• 出版日期2011-11-18