Facile synthesis of 2H-indazole derivatives starting from the Baylis–Hillman adducts of 2-cyclohexen-1-one
摘要:
Facile synthetic method of 2H-indazole derivatives was developed involving DDQ oxidation of pyrazoles, which were prepared starting from the Baylis-Hillman adducts of 2-cyclohexen-1-one. (c) 2005 Elsevier Ltd. All rights reserved.
Substituted (
<i>E</i>
)‐2‐Methylene‐3,4‐cyclohexenones through Direct and Convenient Synthesis from Cyclohexenone‐MBH Alcohol in the Presence of DMAP
作者:Hong‐Xia Ren、Xiang‐Jia Song、Lin Wu、Zhi‐Cheng Huang、Ying Zou、Xia Li、Xiao‐Wen Chen、Fang Tian、Li‐Xin Wang
DOI:10.1002/ejoc.201801301
日期:2019.1.31
An unexpected new reaction of cyclohexenone‐MBH alcohol catalyzed by DMAP has been successfully disclosed to prepare a series of substituted (E)‐2‐methylene‐3,4‐cyclohexenones in excellent yields (up to 93 %) under convenient reaction conditions. Scale‐up preparation and synthetic transformations have been conducted.
Conjugated cyclic enones react smoothly in water with a variety of aldehydes (Baylis-Hillman reaction) in the presence of surfactants above their critical micelle concentrations (CMC).
The Baylis–Hillman condensation of α,β-conjugate cycloketones with aldehydes using diethylaluminum iodide alone as the promoter
作者:Wei Pei、Han-Xun Wei、Guigen Li
DOI:10.1039/b206736f
日期:——
The Baylis-Hillman condensation of three types of α,β-conjugate cycloketones with aldehydes was successfully performed by using diethylaluminum iodide as the Lewis acid promoter alone without the direct use of a Lewis base. The reaction proceeded to completion at 0 °C in CH2Cl2 within 24 h to give modest to good yields (53â72%).
Rhodium(II)-Catalyzed Reaction of 1-Tosyl-1,2,3-triazoles with Morita-Baylis-Hillman Adducts: Synthesis of 3,4-Fused Pyrroles
作者:Renmeng Jia、Jiang Meng、Jiaying Leng、Xingxin Yu、Wei-Ping Deng
DOI:10.1002/asia.201800057
日期:2018.9.4
A cascade reaction of rhodium azavinylcarbenes with Morita–Baylis–Hillman (MBH) adducts enables a novel synthetic approach to 3,4‐fused pyrroles. The cascade reaction begins with the insertion of O−H bond into rhodium azavinylcarbenes, subsquent sigmatropic rearrangement provides substituted α,β‐unsaturated cyclic ketone intermediates. Then the intramolecular aza Michael addition/oxidative aromatization
<i>N</i>-Methylpyrrolidone Hydroperoxide/Cs<sub>2</sub>CO<sub>3</sub>as an Excellent Reagent System for the Hydroxy-Directed Diastereoselective Epoxidation of Electron-Deficient Olefins
作者:Napoleon John Victor、Janardhanan Gana、Kannoth Manheri Muraleedharan
DOI:10.1002/chem.201501929
日期:2015.10.12
This report introduces N‐methylpyrrolidone hydroperoxide (NMPOOH)/base as an excellent reagent system for hydroxy‐directed syn selective epoxidation of electron‐deficient olefins, characterized by high diastereoselectivity, short reaction times and remarkable chemoselectivity, especially in presence of oxidatively labile nitrogen or sulfur atoms. NMPOOH also proves efficient in the oxidation of electron‐deficient