A route to biaryl-3-carboxylate esters involving a radical 1,2-aryl migration has been developed. This strategy hinges on the radical addition of xanthate 2 to olefin 1 causing a 1,2-aryl shift leading to alpha,beta-unsaturated ester 5, which is then converted into biaryl 10 by treatment with DBU under microwave heating.
Tri- and Tetrasubstituted Functionalized Vinyl Sulfides by Radical Allylation
作者:Laurent Debien、Marie-Gabrielle Braun、Béatrice Quiclet-Sire、Samir Z. Zard
DOI:10.1021/ol403103u
日期:2013.12.20
2-Fluoropyridinyl-6-oxy- precursors derived from phenyl vinyl sulfide react with radicals generated from xanthates via an addition–elimination process to furnish the corresponding vinyl sulfides in good yields. This convergent method is operationally simple and enables a straightforward synthesis of the difficult to access tetrasubstituted vinyl sulfides. Vinyl sulfides were used as more robust enol ether surrogates
作者:Béatrice Quiclet-Sire、Guillaume Revol、Samir Z. Zard
DOI:10.1016/j.tet.2010.05.107
日期:2010.8
Various xanthates can be added to N-vinyl phthalimide with little formation of oligomers, if the xanthate is used in excess and the medium slightly diluted. The adduct xanthates thus obtained can in turn undergo radical additions to numerous olefins, providing a convergent and modular access to densely functionalized amines. (C) 2010 Elsevier Ltd. All rights reserved.
Modular Approach to Substituted Boc-Protected 4-(Aminomethyl)pyrroles
作者:Songzhe Han、Samir Z. Zard
DOI:10.1021/ol500544u
日期:2014.4.4
The radical addition of various alpha-xanthyl ketones to Boc-protected azetine gives adducts which, when treated with ammonia or primary amines, furnish 2,4-disubstituted, 2,3,4-trisubstituted, and polycyclic pyrroles having a protected aminomethyl group at position 4. An unusual ring-opening was observed in the case of a cyclobutanone precursor.