Properties of Isothiazoles

Physical Characteristics of Isothiazoles Isothiazole, like its simple alkyl derivatives, is a mobile, colorless liquid, df 1.1706, mf) 1.5320, b.p. 114°, with an odor resembling 

Hubenett, F. H. Flock, W. Hansel, H. Heinze, and H. Hofmann, Angew. Chem. Intern. Ed. Engl. 2, 714 (1963). 

Adams and Slack compared the electron densities and mobile bond orders of the parent molecule (21) with those of thiazole (22) and pyridine (23). Overlap was neglected in these simplified calculations, 

On the laboratory scale, isothiazole is most conveniently prepared by the acetylenic route. On the other hand, the olefinic route has 

The substitution properties of isothiazole are in broad agreement with the electron distribution pattem. Thus, electrophilic substitution occurs predominantly in the 4-position, if this is free, and metalation in the 5-position. The ring appears to be stable to acid, alkali, and mild oxidation and forms a chloroplatinate and an unstable mercurichloride.  

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Chiroptical properties of isothiazole derivatives have been studied using circular dicroism (CD). Optically active sulfinamide R- +)-49a. (R=l-Ad) shows a positive first Cotton effect at 284nm while A (- -)-49b (R = 2,4,6-Me3C6H2) has a negative one at 277 nm <2005JOC868>. 

Physical Properties of Isothiazoles and Isothiazolines. - HUckel molecular orbital calculations have been performed for a large number of 5-membered rings with 1 or 2 heteroatoms, including isothiazoles. The calculated relative order of stabilities... 

Synthesis of Isothiazoles, Isothiazolines, and Isothiazolidines 151 From amidoketones and hydrogen sulphide (Type A C-C-C-N + S) 151 From iminonitriles and mercaptoacetic acid derivatives (Type B C-C-N + S-C) 151 From cyclisation of enaminothiones (Type C N-C-C-C-S) 152 From sulphonamidoacetates and diethyl oxalate (N-S-C + C-C) 152 From ketenes and sulphur di-imides (N-S-C + C-C) 152 Physical Properties of Isothiazoles and Isothiazolines 152 Chemical Properties of Isothiazoles, Isothiazolines, and Isothiazolidines 153... 

Chemical Properties of Isothiazoles, Isothiazolines, and Iso-thiazolidines. - Diazotisation and subsequent azo coupling of various 5 amino-3 l-disubstituted isothiazoles has been reported. 

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