Direct Catalytic Asymmetric Vinylogous Additions of α,β‐ and β,γ‐Butenolides to Polyfluorinated Alkynyl Ketimines
作者:Barry M. Trost、Chao‐I. (Joey) Hung、Manuel J. Scharf
DOI:10.1002/anie.201806249
日期:2018.8.27
We report a Zn‐ProPhenol catalyzed asymmetric Mannich reaction between butenolides and polyfluorinated alkynyl ketimines to obtain vinylogous products featuring two contiguous tetrasubstituted stereogenic centers. Notably, this is the first successful use of ketimines in the ProPhenol Mannich process, and the reaction offers a new approach for the preparation of pharmaceutically relevant products possessing
Synthesis of Polysubstituted Trifluoromethylpyridines from Trifluoromethyl-α,β<i>-</i>ynones
作者:Tianyu Yang、Zhoubin Deng、Ke-Hu Wang、Pengfei Li、Danfeng Huang、Yingpeng Su、Yulai Hu
DOI:10.1021/acs.joc.9b02873
日期:2020.1.17
trifluoromethylpyridine derivatives by the Bohlmann-Rahtz heteroannulation reaction is described, which use trifluoromethyl-α,β-ynones as trifluoromethyl building blocks to react with β-enamino esters or β-enamino ketones in the presence of ZnBr2 to form the trifluoromethylpyridine derivatives in good yields. The protocol has the advantages of readily available starting materials, mild reaction conditions, and
PROCESSES FOR THE PREPARATION OF 1,5-DIARYLPYRAZOLES
申请人:——
公开号:US20030096853A1
公开(公告)日:2003-05-22
Provided are processes for the preparation of the compound of the formula
1
wherein R
1
, R
3
and R
4
are independently selected from the group consisting of hydrogen, halogen, hydroxyl, nitro, lower alkyl, lower alkoxy, carboxy, C
1
-C
6
trihaloalkyl, and cyano, and R is amino or lower alkyl
Also provided are synthetic intermediates that are useful as intermediates in the preparation of the compound of the formula 1.
Processes for the preparation of 1,5-diaryl-3-substituted-pyrazoles
申请人:——
公开号:US20030109709A1
公开(公告)日:2003-06-12
Provided are processes and chemical intermediates useful for preparing a compound of the formula I
1
wherein
X is selected from the group consisting of C
1
-C
6
trihalomethyl; C
1
-C
6
alkyl; and an optionally substituted or di-substituted phenyl group of formula II:
2
Y and Z are independently selected from the group consisting of substituted and unsubstiotuted aryl
Regioselective Synthesis of 2,4-Diaryl-6-trifluoromethylated Pyridines through Copper-Catalyzed Cyclization of CF<sub>3</sub>-Ynones and Vinyl Azides
作者:Jixin Wang、Da Ba、Mengqi Yang、Guolin Cheng、Lianhui Wang
DOI:10.1021/acs.joc.1c00275
日期:2021.5.7
copper-catalyzed cyclization of readily available vinyl azides with CF3-ynones is steadily achieved under mild conditions to furnish the versatile 2,4-diaryl-6-trifluoromethylated pyridineproducts, which are of great interest in medicinal chemistry. The generation of the vinyl iminophosphorane intermediates from vinyl azides through the Staudinger–Meyer reaction ensures the subsequent 1,4-addition process with