A transition-metal-free multicomponent reaction towards constructing chiral 2<i>H</i>-1,4-benzoxazine scaffolds
作者:Lixiang Zhu、Xiaoyu Ren、Juan Du、Jia-Hong Wu、Jian-Ping Tan、Jixing Che、Jianke Pan、Tianli Wang
DOI:10.1039/d0gc02134b
日期:——
transition-metal-free multicomponent cascade reaction of readily available α-halogenated ketones, ortho-aminophenols, and aldehydes using a novel dipeptide-based phosphonium salt catalyst was developed for the efficient construction of various 2H-1,4-benzoxazine derivatives with excellent functional-group tolerance. The method represents an unprecedented approach for trapping active 1,5-bifunctional intermediates
本文中,开发了一种使用新型的基于二肽的phospho盐催化剂的易于获得的α-卤代酮,邻氨基酚和醛的无过渡金属的多组分级联反应,以有效地构建各种2 H -1,4-苯并恶嗪具有出色的官能团耐受性的衍生物。该方法代表了一种空前的方法,用于捕获具有α-卤代酮的活性1,5-双功能中间体,以访问具有两个非立体诱导中心且具有两个立体生成中心的生物学上重要的苯并恶嗪支架。
Catalyst-free allylation of 2-aminophenol–derived aldimines with allyltrichlorosilane under thermal conditions
作者:Kesa Venkatanna、Chinnasamy Ramaraj Ramanathan
DOI:10.1016/j.tetlet.2017.08.012
日期:2017.9
Allylation of 2-aminophenol-derived aldimines using allyltrichlorosilane undercatalystfreeconditions has been developed. This reaction afforded the corresponding homoallylic amines in good to excellent yields (68–94%). The salicylaldehyde-derived aldimines as well as benzoylhydrazone also found to react with allyltrichlorosilane smoothly under the same conditions, to furnish the corresponding homoallylic
Effect of substituents on the UV spectra of supermolecular system: Silver nanoparticles with bi-aryl Schiff bases containing hydroxyl
作者:Chao-Tun Cao、Shimao Cheng、Jingyuan Zhang、Chenzhong Cao
DOI:10.1002/poc.3910
日期:2019.3
Effect of substituents on the ultraviolet (UV) spectra of supermolecular system involving silver nanoparticles (AgNPs) and Schiffbases was investigated. AgNPs and 49 samples of model compounds (MC), bi‐aryl Schiffbases containing hydroxyl (XBAY, involving 4‐OHArCHNArY, 2‐OHArCHNArY, XArCHNAr‐4′‐OH, and XArCHNAr‐2′‐OH), were synthesized. The size of AgNPs was characterized by transmission electron
Neighboring phenolic group-activated <i>gem</i>-difluoroallylboration of imines for the catalyst-free synthesis of <i>gem</i>-difluorohomoallylamines
作者:Xing Yang、Feng Zhang、Yang Zhou、Yi-Yong Huang
DOI:10.1039/c8ob00541a
日期:——
We herein report an unprecedented addition reaction of pinacol gem-difluoroallylborates and imines enabled by a neighboring phenolic group in an N-protecting group under catalyst-free conditions, thus facilitating the construction of a wide range of racemic gem-difluorohomoallylamine derivatives. Based on the control experiments, a plausible transition state via the Zimmerman–Traxler model was proposed