New routes for the synthesis of 3- and 5-substituted 2(1H)-pyrazinones
作者:Rasha Azzam、Wim De Borggraeve、Frans Compernolle、Georges J Hoornaert
DOI:10.1016/j.tetlet.2004.01.017
日期:2004.2
Furthermore, following hydrogenolysis of the 5-chloro substituent and regioselective 5-bromination, this palladium-catalysed cross-coupling approach could be extended to the synthesis of the analogous 5-substituted 2(1H)-pyrazinones.
Expanding the substitution pattern of 2(1H)-pyrazinones via Suzuki and Heck reactions
作者:Rasha Azzam、Wim M. De Borggraeve、Frans Compernolle、Georges J. Hoornaert
DOI:10.1016/j.tet.2005.02.056
日期:2005.4
Various 3,5-dichloropyrazinones were substituted at the C-3 position with (hetero)aryl, alkyl and alkenyl groups by means of Suzuki and Heck reactions. The methodology could be extended to reactions on the far less reactive C-5 position by transhalogenation of the 5-Cl substituent to a 5-Br or a 5-I group prior to performing the cross-coupling. (c) 2005 Elsevier Ltd. All rights reserved.