Trimethine thiazolocyanines, absorption

Trimethine thiazolocyanines. absorption of, in relation with chain substitution. 77... 

Due to the structure of the symmetrical anhydrobase. every time a 2-methylthiazolium undergoes the attack of a base, theoretically it can result in two trimethine thiazolocyanines the mesomethylsubstituted one and the unsubstituted one. For an unexplained reason, it seems that when position 5 of the starting molecule is substituted, only the mesomethyl dye is produced according to the absorption spectrum, 530 nm for the methylmeso and 569 nm for the 4-phenyl substituted derivative (Scheme 29). ... 

Whatever their nature may be, phenyl or alkyl, the substituents of the thiazole ring in position 4 or 5 give a bathochromic shift (110, 111) of the absorption of a symmetrical trimethine thiazolocyanine compared to an unsubslituted dye. For a given substituent, this shift is greater for position 5 than for 4 (112). 

Ortho esters, in synthesis of symmetrical trimethine thiazolocyanines, 54 Oxazolone, for neutrocyanines, 27 Oxidation potentials, of dyes, 75 of mesosubstituted dyes, in relation with absorption, 77 of polymethine dyes, 72 Oxidoreduction, relation between sensitizers, and silver halides, 78 4-Oxo-disubstituted 2-aminoselenazoles, table of products, 262 Oxonols, nomenclature of, 26 in synthesis of dimethine neutrocyanines, 62... 

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