Nickel-Catalyzed Synthesis of Stereochemically Defined Enamides via Bi- and Tricomponent Coupling Reaction
摘要:
The stereoseleetive synthesis of (E)-trisubstituted tertiary enamides is documented via site-selective Ni-catalyzed beta-arylation of allenamides with boronic acids in high yields (up to 89%). The nucleophilic character of the "organo-Ni" intermediates is further exploited to implement a one-pot tricomponent procedure involving the final allylation of aldehydes (yields up to 93%). Mechanistic insights and efficiency on a gram scale process were also documented.
Synthesis of sterically hindered enamides via a Ti-mediated condensation of amides with aldehydes and ketones
作者:Julien Genovino、Bharat Lagu、Yaping Wang、B. Barry Touré
DOI:10.1039/c2cc32538a
日期:——
The first TiCl(4)-mediated condensation of secondary amides with aldehydes and ketones has been achieved. The reaction proceeds at room temperature and is complete within 5 h in most cases. The optimized procedure used 5 equiv of an amine base hinting that the in situ activation of both the amide and the Lewis acid is required. The reaction affords polysubstituted (E)-enamides.