The first chemoselective tandem acylation of the Blaise reaction intermediate: a novel method for the synthesis of α-acyl-β-enamino esters, key intermediate for pyrazoles
作者:Yu Sung Chun、Ki Kon Lee、Young Ok Ko、Hyunik Shin、Sang-gi Lee
DOI:10.1039/b813369g
日期:——
The Blaise reaction intermediate, a zinc bromide complex of β-enamino ester, could be activated in situ by addition of a stoichiometric or catalytic amount of n-BuLi to allow chemoselective tandem C2-acylation providing α-acyl-β-enamino esters, which are valuable intermediates for the syntheses of tri- and tetrasubstituted pyrazoles.
Efficient Synthesis of Pyrazoles: Oxidative CC/NN Bond-Formation Cascade
作者:Julia J. Neumann、Mamta Suri、Frank Glorius
DOI:10.1002/anie.201002389
日期:2010.10.11
Golden section: A novel synthetic strategy for the synthesis of tetrasubstituted pyrazoles is provided. In an efficient CC/NNbond‐formation cascade, enamines and nitriles are oxidatively coupled to deliver pyrazoles in good yields (see scheme). The ready availability of the starting materials, the high level of practicability of the reaction and work up, and the avoidance of hydrazine starting materials
黄金部分:提供了一种合成四取代吡唑的新颖合成策略。在有效的C CC / NN键形成级联反应中,烯胺和腈氧化偶联以高产率提供吡唑(请参阅方案)。起始原料的容易获得,反应和后处理的高度实用性以及避免使用肼起始原料,使得该方法具有吸引力。
PYRAZOLE SYNTHESIS BY COUPLING OF CARBOXYLIC ACID DERIVATIVES AND ENAMINES
申请人:Neumann Julia
公开号:US20130012715A1
公开(公告)日:2013-01-10
The invention describes a novel process for synthesizing pyrazoles by means of oxidative conversion of enamines with suitable N-containing carboxylic acid derivatives.