Synthetically useful [1,2-a]-fused pyrroles, e.g. 2,3-dihydro-1H-pyrrolizidines substituted in the 1- and 7-positions, have been generated by acyl radical cyclisation onto pyrroles using N-(omega -acyl)-radicals generated front acyl-selenide precursors. The protocol does not require high pressures of CO. Mechanistic studies indicate the key role of azo radical initiators as oxidants of the intermediate pi -radicals. (C) 2001 Elsevier Science Ltd. All rights reserved.
作者:Steven M Allin、William R.S Barton、W.Russell Bowman、Tom McInally
DOI:10.1016/s0040-4039(01)01639-2
日期:2001.10
Synthetically useful [1,2-a]-fused pyrroles, e.g. 2,3-dihydro-1H-pyrrolizidines substituted in the 1- and 7-positions, have been generated by acyl radical cyclisation onto pyrroles using N-(omega -acyl)-radicals generated front acyl-selenide precursors. The protocol does not require high pressures of CO. Mechanistic studies indicate the key role of azo radical initiators as oxidants of the intermediate pi -radicals. (C) 2001 Elsevier Science Ltd. All rights reserved.