Nitrogen- and Sulphur-containing Heterocycles

Nitrogoi and Sulphur-containii Heterocycles.—A general synthesis of 4,5-dihydro-thiazol-2-yl heterocycles has been achieved by reaction of the anion of the hetero-cycle with chloroethylisothiocyanate displacement of halogen was followed by 

Mosinger, and W. Schuckmann, Angew. Chem. Internat. Edn., 1976, 15, 103. 

3-Dimethylamino-2,2-dimethylazirine reacted with carbon disulphide to give crystals with the structure (337) in solution this compound existed in the isomeric form (338). Reaction products were derived from both structures, and over 20 new derivatives were prepared by reaction with simple reagents. Two examples are shown thermolysis of (338) caused rearrangement to (340) in high yield, and treatment of (337) with dilute acid gave an 84% yield of (339), but these examples hardly do justice to this excellent paper by the late Hans Schmid.  

L Abbe and Verhelst have described a one-pot synthesis of 5-arylimino-l,2,4-thiadiazolidine-3-ones in high yields by adding an isothiocyanate in portions during 

Chaloupka, H. Heimgartner, H. Schmid, H. Link, P. Schonholzer, and K. Bernauer, Helv. 

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C18 Reversed phases are not necessarily limited to polycyclic and halogenated (or nitrated) hydrocarbons, but can be used for a number of oxygen-, nitrogen- and sulphur- containing heterocyclic compounds in a similar way to that used in reversed-phase chromatography. In this context, ref. 185 describes the separation of compounds of this category. A plethora of similar separations can be found in the Section devoted... 

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