Borane-Catalyzed Reductive α-Silylation of Conjugated Esters and Amides Leaving Carbonyl Groups Intact
作者:Youngchan Kim、Sukbok Chang
DOI:10.1002/anie.201508669
日期:2016.1.4
valuable α‐silyl carbonyl products. The α‐silylation occurs chemoselectively, thus leaving the labile carbonylgroups intact. The reaction features a broad scope of both acyclic and cyclic substrates, and the synthetic utility of the obtained α‐silyl carbonyl products is also demonstrated. Mechanistic studies revealed two operative steps: fast 1,4‐hydrosilylation of conjugated carbonyls and then slow
本文描述了由B(C 6 F 5)3催化的α,β-不饱和酯和酰胺的氢化硅烷化反应,以提供具有合成价值的α-甲硅烷基羰基产物。α-甲硅烷基化是化学选择性发生的,因此保留了不稳定的羰基。该反应具有无环和环状底物的广泛范围,并且还证明了所得α-甲硅烷基羰基产物的合成效用。机理研究揭示了两个操作步骤:共轭羰基的快速1,4-氢化硅烷化,然后减慢甲硅烷基醚中间体的甲硅烷基迁移。
Stereoselective Olefination Reactions Promoted by Rieke Manganese
作者:José Concellón、Humberto Rodríguez-Solla、Vicente del Amo、Pamela Díaz
DOI:10.1055/s-0029-1216880
日期:2009.8
applied to develop a novel and direct synthesis of (E)-α,β-unsaturated esters or amides and (Z)-α,β-unsaturated α-halo esters and α-choroamides through a Mn*-mediated sequential olefination protocol of aldehydes with dichloro esters or amides and trihalo esters or trichloroamides, respectively. manganese - elimination reactions - stereoselectivity - α,β-unsaturated esters - α,β-unsaturated amides - metalation
Hexafluoroisopropanol and Acetyl Chloride Promoted Catalytic Hydroarylation with Phenols
作者:Sudeshna Roy、Hashim F. Motiwala、Karl M. Koshlap、Jeffrey Aubé
DOI:10.1002/ejoc.201701256
日期:2018.1.23
HFIP facilitates the mild catalytic hydroarylation of phenols to provide dihydrocoumarins using sub‐stoichiometric amounts of acetylchloride as catalyst.
A facile and convenient protocol for the synthesis of cinnamides from cinnamic acids and tetraalkylthiuram disulfides under metal and additive free conditions has been achieved. This method allows the efficient coupling of diverse cinnamic acids with tetraalkylthiuram disulfides through a simply mixing operation.