Synthesis of indazole- N -oxides via the 1,7-electrocyclisation of azomethine ylides
作者:Miklós Nyerges、Imre Fejes、Andrea Virányi、Paul W Groundwater、László Tőke
DOI:10.1016/s0040-4039(01)00892-9
日期:2001.7
The first example of the 1,7-electrocyclisation of a non-stabilised azomethine ylide, e.g. 2, onto a nitro group, to give a 1,2,6-oxadiazepine intermediate, e.g. 4, is reported. Subsequent ring contraction results in the formation of the indazole-N-oxides 5, 12, and 14. (C) 2001 Elsevier Science Ltd. All rights reserved.