1,3,5-Triazines, perfluoroalkyl-, synthesis

The benzimidoyl thiocarbodihydrazide (237) was cyclized by Soviet chemists to yield 3-phenyl-l,4-dihydro-l,2,4,5-triazine-6(5//)-thione (238). But since (237) was prepared by reaction of ethyl benzimidate and thiocarbodihydrazide this reaction can also be classified as a synthesis by a [5 + 1] atom fragment method (77KGS564). When the perfluoroalkyl hydrazidines (239) were heated with anhydrous iron(III) chloride, cyclization occurred with... 

Due to the availability of perfluoroalkyl iodides, this method quickly became the method of choice for the regioselective synthesis of perfluoroalkylated heterocycles. Chen and Tamborski used this reaction for the preparation of variety perfluoroalkyl-pyridines," azines," and triazines." For example, pyridines 72-73 and pyrimidine 74 were synthesized by addition of perfluorohexyl iodide to the agitated mixture of the corresponding heteroaryl bromide, cooper bronze powder in DMSO solvent under nitrogen at elevated temperature (Fig. 7.26)." ... 

A number of patents and papers dealing with the synthesis of fluorinated jym-triazines and related triazine-linked polymers via cyclotrimerization of fluoroalkyl cyanides,or cyclization reactions of per- and poly-fluoro-imidoylamidines (see p. 15), and the use of tris(perfluoroalkyl)-s3 /n-... 

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