Dichotomous reactivity in stannane and cobalt mediated radical cyclisations
作者:Michael J Begley、Harcharan Bhandal、John H Hutchinson、Gerald Pattenden
DOI:10.1016/s0040-4039(00)95358-9
日期:1987.1
The stereospecificity of the 5--trig radical cyclisation of the bromo-acetal (2) [to (1) or (3)] is dependent on the initiation used; Bu3Sn leads to (1) predominantly whereas Co(I) produces diastereoisomer (3). An explanation for this dichotomous reactivity, implicating cobalt-bonded intermediates of the type (9) and (10), is offered.