Conversion of bis(o-nitrophenyl)disulfides to heterocycles containing sulfur and nitrogen by the action of samarium diiodide
作者:Weihui Zhong、Xiaoyuan Chen、Yongmin Zhang
DOI:10.1002/hc.1025
日期:——
Treatment of bis(o-nitrophenyl)disulfides 1 with SmI2 led to simultaneous reduction of nitro groups and reductive cleavage of S–S bonds as well as the formation of the active intermediates 2. The intermediates 2 reacted smoothly with aldehydes or ketones, acid chlorides or anhydrides, α-bromoketones, and α,β-unsaturated ketones at room temperature to afford the desired benzothiazolines 3, benzothiazoles
A process for producing an optically active amine compound, characterized by asymmetrically hydrogenating a prochiral carbon-nitrogen double bond in the presence of a ruthenium complex represented by general formula (1) or (2) (wherein P
represents an optically active diphosphine, X represents an anionic group, and Ar represents an optionally substituted arylene group).
Synthesis and stereochemistry of Δ<sup>2,2′</sup>-bi-(2H-1,4-benzothiazine) derivatives. Crystal structures of cis- and trans-Δ<sup>2,2′</sup>-bi-(3-p-bromophenyl-2H-1,4-benzothiazine)
isomers has been explained in terms of the molecular structures of the cis- and trans- isomers of the 3-p-bromophenyl derivative (IIa) which were determined by three-dimensional X-ray analysis. The cis-isomer crystallizes in space group P, with Z= 2, in a unit cell of dimensions a= 10·18, b= 12·90, c= 10·65 Å, α= 113° 56′, β= 95° 57′, γ= 103° 5′. Crystals of the trans-isomer are monoclinic, space group
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.