Iridium and copper supported on silicon dioxide as chemoselective catalysts for dehydrogenation and borrowing hydrogen reactions
作者:Guanxin Zhu、Zheng-Chao Duan、Haiyan Zhu、Minghui Qi、Dawei Wang
DOI:10.1016/j.mcat.2021.111516
日期:2021.4
benzotriazole-pyridinyl-silane ligand (BPS) was designed, and the corresponding iridium and copper catalysts were synthesized and thoroughly characterized by means of EDS, TEM, and XPS. The resulting iridium composite revealed excellent catalytic activity for the reaction of tert-butanesulfinamide with benzyl alcohols, while copper catalyst could realize the synthesis of unsaturated carbonyl compounds through
This work describes an electrochemicalammoniumcation enabled hydropyridylation of ketone-activated alkenes under metal- and exogenous reductant free conditions giving access to β-pyridyl ketones, through dual proton-coupled electron transfer and radical cross-coupling. It features a broad substrate scope and allows a gram-scale synthesis. Ammonium chloride plays various roles in this transformation
Asymmetric Enamide–Imine Tautomerism in the Kinetic Resolution of Tertiary Alcohols
作者:Mengyao Tang、Huanchao Gu、Shunlong He、Subramani Rajkumar、Xiaoyu Yang
DOI:10.1002/anie.202106151
日期:2021.9.20
of racemic 2-arylsulfonamido tertiary allyl alcohols could be kinetically resolved with excellent kinetic resolution performances (with s-factor up to >200). This method is particularly effective for a series of 1,1-dialkyl substituted allyl alcohols, which produced chiral tertiary alcohols that would be difficult to access via other asymmetric methods. Facile and versatile transformations of the chiral
A transition metal-free cascade reaction using heterogeneous tin(IV)oxide catalyzed and iodine promoted synthesis of 3-aroylimidazo[1,2-a]pyridines
作者:Nirajkumar H. Jadhav、Sachin S. Sakate、Dnyaneshwar R. Shinde、Manohar G. Chaskar、Ramdas A. Pawar
DOI:10.1016/j.tetlet.2020.152250
日期:2020.8
synthesis of 3-aroylimidazo[1,2-a]pyridines. The methodology was further extended for the one-pot three-component synthesis of 3-aroylimidazo[1,2-a]pyridines using acetophenone, benzaldehyde, and 2-aminopyridine derivatives. The present protocol describes the easy purification methodology in the synthesis of 3-aroylimidazo[1,2-a]pyridines.
在环境空气气氛下,通过SnO 2 / I 2催化体系在甲苯中使用查尔酮和2-氨基吡啶实现了3-芳基咪唑并[ 1,2 - a ]吡啶的级联合成。在3-芳基咪唑并[1,2]合成过程中,该催化剂对具有2-氨基吡啶,4-甲基2-氨基吡啶和5-甲基2-氨基吡啶的各种芳族和杂环查耳酮的广泛底物范围显示出高活性。-一个]吡啶。该方法进一步扩展为使用苯乙酮,苯甲醛和2-氨基吡啶衍生物一锅法合成3-芳基咪唑并[ 1,2 - a ]吡啶。本协议描述了3-芳基咪唑并[ 1,2 - a ]吡啶的合成中的简便纯化方法。
TMSOTf-mediated Kröhnke pyridine synthesis using HMDS as the nitrogen source under microwave irradiation
作者:Chieh-Kai Chan、Yi-Hsiu Chung、Cheng-Chung Wang
DOI:10.1039/d2ra00084a
日期:——
An efficient protocol for the preparation of pyridine skeletons has been successfully developed involving the TMSOTf/HMDS (trifluoromethanesulfonic acid/hexamethyldisilane) system for the intermolecular cyclization of chalcones under MW (microwave) irradiation conditions. This method provides a facile approach to synthesize 2,4,6-triaryl or 3-benzyl-2,4,6-triarylpyridines in good to excellent yields