研究了甲醇催化取代的亚苄基萘以及正和邻甲基邻苯基乙酰苯甲酸甲酯形成2-苯基茚满-1,3-二酮的重排的详细机理。在甲醇二甲基亚砜(DMSO)中反应的速率-酸度函数相关性显示速率随H _线性增加,在对硝基底物除外之前达到最大速率。该导数显示出在整个H _范围内速率降低。甲醇和94 mol%的DMSO中的ρ值分别为1.7和–1.6。在k H / k D下观察到了动力学同位素效应0.8-1.0。已经确定了邻苯基乙酰基苯甲酸甲酯的环链互变异构的平衡常数,并且该常数不依赖于取代基和溶剂组成。决定速率的步骤是正酸酯的阴离子在酯羰基上的分子内攻击。在甲醇和高甲醇含量的甲醇DMSO中,这之前是正酸酯的电离平衡。在低甲醇含量的甲醇DMSO中,对于对硝基底物,初始状态是阴离子本身。
α-Thiocyanation of Carbonyl and β-Dicarbonyl Compounds Using (Dichloroiodo)benzene−Lead(II) Thiocyanate
作者:Om Prakash、Harpreet Kaur、Hitesh Batra、Neena Rani、Shiv P. Singh、Robert M. Moriarty
DOI:10.1021/jo001504i
日期:2001.3.1
combination reagent (dichloroiodo)benzene and lead(II) thiocyanate in dichloromethane effects oxidation of various enolsilylethers, ketene silyl acetals, and beta-dicarbonyl compounds, thereby providing an efficient and convenient method for alpha-thiocyanation of carbonyl and beta-dicarbonyl compounds.
Efficient and convenient synthesis, characterization, and antimicrobial evaluation of some new tetracyclic 1,4-benzothiazines
作者:Satbir Mor、Savita Nagoria
DOI:10.1080/00397911.2015.1127383
日期:2016.1.17
ABSTRACT In the present study, 20 new tetracyclic 1,4-benzothiazines (4a–4 t) were conveniently synthesized in good yields and characterized by different spectral and physical techniques. The in vitro antimicrobial evaluation of the synthesized benzothiazine derivatives was performed by serial dilution against two Gram-positive bacteria [Bacillus subtilis (MTCC 441) and Staphylococcus epidermidis (MTCC
allowing selective access to tertiary alkylated ketones and alkenes. The present approach features commercially available starting materials, broad substrate scope, general functional-group (including halogen, ester, nitrile, thioether) tolerance. Furthermore, we proposed plausible pathways to rationalize the divergent selectivity through preliminary mechanism study.
An Improved Iodine(III) Mediated Method for Thiocyanation of 2-Arylindan-1,3-diones, Phenols, and Anilines
作者:Om Prakash、Harpreet Kaur、Rashmi Pundeer、R. S. Dhillon、Shiv P. Singh
DOI:10.1081/scc-120026343
日期:2003.12.1
An improved method for thiocyanation of 2-arylindan-1,3-diones, phenols, and anilines using a reagent combination of (dichloroiodo)benzene and potassium thiocyanate in dry dichloromethane is described.