97462-64-1Relevant academic research and scientific papers
Intramolecular homolytic aromatic substitution of alkyl 2-benzimidazolyl sulfones as a means of entry into alkyl radicals for organic synthesis
Crich, David,Grant, Daniel
, p. 2999 - 3003 (2008/09/20)
The intramolecular radical aromatic substitution of heteroaryl sulfones by tethered aryl radicals has been investigated as a source of alkyl radicals. The 1-(2-iodobenzyl)benzimidazole-2-sulfonyl system was found to be the most effective, while a tetrazole-based system did not undergo the desired radical aromatic substitution at all. Application of the benzimidazole-based system to the generation of alkyl radical and their subsequent use in radical cyclizations was demonstrated.
Synthesis of the Pyrrolidine Ring System by Radical Cyclization
Padwa, Albert,Nimmesgern, Hildegard,Wong, George S. K.
, p. 5620 - 5627 (2007/10/02)
A series of bromo-substituted allyl- and diallyl-substituted sulfonamides have been found to undergo free radical cyclization when treated with tri-n-butyltin hydride in the presence of AIBN.The regiochemical course of the cyclization depends on the nature of the substituent groups attached to the ?-bond.The stereoelectronic factors governing the cyclization reaction of these N-allylsulfonamides are even more stringent than those which occur with the simple 5-hexenyl system.This is probably related to the shorter C-N bond distance which promotes the 5-exo trigcyclization pathway.The present method provides an attractive entry to the preparation of pyrrolidines from easily available N-(2-bromoethyl)-N-allyl- and N-(2-bromopropenyl)-N-allylsulfonamides.The method represents a clear-cut example of the use of hetero-substituted radicals in C-C bond-forming processes.
Radical cyclization as an approach toward the synthesis of pyrrolidines
Padwa, Albert,Nimmesgern, Hildegard,Wong, George S.K.
, p. 957 - 960 (2007/10/02)
Free radical cyclizations of several bromo allyl and diallyl substituted sulfonamides are described. The regiochemical course of these cyclizations depend on the nature of the substituent groups attached to the π-bond.
