4- Bromo-5-methyl-2-phenylthiazole

Nontraditional photochromes with high absorption coefficients of the colored isomers 94B and 95B are worthy of notice. These compounds were synthesized from 2-bromo-3-methyl-2-butene and 4-bromo-5-methyl-2-phenylthiazole, respectively, with BuLi and the corresponding monofluorides (05MI2467) (Scheme 31). 

Non-traditional photochromes 95 and 96 were synthesized by the reactions of 2-bromo-3-methyl-2-bntene and 4-bromo-5-methyl-2-phenylthiazole with BnLi and the corresponding monoflnorides [102] (Scheme 35) and new photochromic di-arleth-enes 97 bearing both the thiazole and benzene moieties that exhibit fluorescence in solution and in the PMMA film [103] are worth mentioning. 

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