945546-61-2Relevant academic research and scientific papers
Formal radical closure onto aromatic rings-a general route to carbocycles
Clive, Derrick L. J.,Sunasee, Rajesh,Chen, Zhenhua
experimental part, p. 2434 - 2441 (2009/02/02)
A general method is described for indirectly effecting radical carbocyclization of an alkyl chain onto an aromatic ring. Birch reductive-alkylation of aromatic tert-butyl esters with α,ω- dibromides, chromium(vi)-mediated oxidation of the resulting 1,4-dienes and Finkelstein displacement of Br- with NaI gives cross-conjugated ketones that undergo radical cyclization. The products are easily aromatized to phenols by silylation, Saegusa oxidation and treatment with BiCl 3.H2O. A special feature of the route is that it allows attachment of a substituent to the original aromatic ring in place of the phenolic oxygen of the normal product.
Formation of benzo-fused carbocycles by formal radical cyclization onto an aromatic ring
Clive, Derrick L. J.,Sunasee, Rajesh
, p. 2677 - 2680 (2008/02/09)
Equation Presented An indirect method for effecting radical carbocyclization onto aromatic rings is described. Cross-conjugated dienones such as 13, readily prepared by Birch reduction of aromatic fert-butyl esters, in situ alkylation, and oxidation (10 → 11 → 12 → 13), undergo radical cyclization; the products (14) are aromatized by silylation, Saegusa oxidation, and treatment with BiCl3·H2O. A noteworthy feature of this route is that it provides opportunities to attach an additional substituent to the original aromatic ring.
