Radical Route to 1,4-Benzothiazine Derivatives from 2-Aminobenzenethiols and Ketones under Transition-Metal-Free Conditions
作者:Ya-mei Lin、Guo-ping Lu、Rong-kang Wang、Wen-bin Yi
DOI:10.1021/acs.orglett.6b03324
日期:2016.12.16
Transition-metal-free radical access to 1,4-benzothiazine derivativesfrom o-aminobenzenethiols is disclosed. This procedure is available for various ketones including α,β-unsaturated, cyclic, linear, and fluoroalkyl ketones to generate a number of 1,4-benzothiazines, which exist in numerous bioactive and natural molecules, rendering this protocol attractive to both synthetic and medicinal chemistry
Bioglycerol-Based Sulfonic Acid-Functionalized Carbon Catalyst as an Efficient and Reusable Catalyst for One-Pot Synthesis of 3- Substituted-2<i>H</i>-1,4-Benzothiazines
作者:Xiaojuan Yang、Liqiang Wu
DOI:10.1080/10426507.2013.765873
日期:2013.10.1
A simple and efficient synthetic protocol has been developed for the synthesis of 3-substituted-2H-1,4-benzothiazines by using bioglycerol-based sulfonic acid-functionalized carbon catalyst, devoid of corrosive acidic and basic reagents. The developed method has the advantages of good to excellent yields, short reaction times, operational simplicity, and a recyclable catalyst.