250355-51-2Relevant articles and documents
Bu3SnH-mediated radical cyclisation onto azoles
Allin, Steven M.,Barton, William R.S.,Russell Bowman,Bridge (née Mann), Emma,Elsegood, Mark R.J.,McInally, Tom,McKee, Vickie
, p. 7745 - 7758 (2008/12/21)
Alkyl radicals have been cyclised onto pyrroles, imidazoles and pyrazoles, and acyl radicals cyclised onto pyrroles, using Bu3SnH-, (TMS)3SiH- and Bu3GeH-mediated aromatic homolytic substitution for the synthesis of bicyclic N-heterocycles. The reactions yield intermediate π-radicals that lose hydrogen in the?rearomatisation step of the aromatic homolytic substitution. Mechanistic studies of these rearomatisation steps indicate aromatic homolytic substitution in which the initiator or breakdown products from the inhibitor are responsible for the H-abstraction step.
Acyl radical cyclisation onto pyrroles
Allin, Steven M.,Barton, William R.S.,Bowman,McInally, Tom
, p. 7887 - 7890 (2007/10/03)
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-(ω-acyl)-radicals generated from 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 π-radicals.
A tandem carbonylation/cyclization radical process of 1-(2-iodoethyl)indoles and pyrrole
Miranda, Luis D.,Cruz-Almanza, Raymundo,Pavon, Miriam,Alva, Edith,Muchowski, Joseph M.
, p. 7153 - 7157 (2007/10/03)
The AIBN-induced radical reaction of 1-(2-iodoethyl)indoles and pyrroles with Bu3SnH under 80 atm of CO was examined. Carbon monoxide was efficiently trapped by an alkyl radical to form an acyl radical which underwent intramolecular addition to the aromatic system to produce bicyclic aromatic ketones after in situ oxidation.