and O-nucleophiles affording the corresponding 5-heterosubstituted isothiazole dioxides through an addition-elimination reaction. The behavior of 3-alkylamino-4-bromo-isothiazole 1,1-dioxide with S-, N- and O-nucleophiles affording the same products has also been described. On the contrary, the 3-amino-4,5-unsubstituted isothiazole dioxide system reacts easily only with sulfur nucleophiles affording
Isothiazolo[5,4-<i>d</i>]isoxazole<i>S,S</i>-dioxides and pyrazolo [3,4-<i>d</i>]-isothiazole<i>S,S</i>-dioxides through cycloaddition reaction on 3-benzylaminoisothiazole<i>S,S</i>-dioxides
作者:Francesca Clerici、Maria Luisa Gelmi、Cristiano Monzani、Donato Pocar、Alessandro Sala
DOI:10.1002/jhet.5570430434
日期:2006.7
dioxides with diazoalkanes and nitrile oxides bicyclic pyrazolo[3,4-d]isothiazole and isothiazolo[5,4-d]isoxazole S,S-dioxides were obtained in good yield through a regioselective cycloaddition reaction. Through cycloaddition reaction of 3-benzylamino-4-bromo-isothiazole S,S-dioxide labile cycloadducts were formed that underwent in situ dehydrobromination affording the corresponding aromatized compounds
通过使4,5-未取代的异噻唑二氧化物与重氮烷烃和腈氧化物反应,通过区域选择性环加成反应以良好的产率获得了双环吡唑并[3,4- d ]异噻唑和异噻唑并[5,4- d ]异恶唑S,S-二氧化物。通过3-苄基氨基-4-溴-异噻唑S的环加成反应,形成了S-二氧化物不稳定的环加合物,其进行了原位脱氢溴化,得到了相应的芳构化化合物。
Enantioselective synthesis, chiroptical properties and absolute configuration of 3-aminosubstituted isothiazole S-oxides
Herein we report a mild and efficient method to synthesize chiral 3-aminosubstituted isothiazole sulfoxides taking advantage of (+)- and (-)-((8,8-dichlorocamphoryl)sulfonyl)oxaziridine under microwave irradiation. The determination of the absolute configuration of the chiral sulfoxide was achieved by theoretical calculation of the CD spectra. The reason for the observed stereoselectivity, was enlightened by means of analysis of our data using DFT calculations. (C) 2009 Elsevier Ltd. All rights reserved.