Diazirines Trifluoromethyldiazirines

Bromo-3(4-nitrophcnyl)-3//-diazirine, 2645 3-Chloro-3-methoxydiazirine, 0734 Chloro-(4-methoxyphenyl)diazirine, 2928 3-Chloro-3-methyldiazirine, 0733 3-Chloro-3-trichloromethyldiazirine, 0610 3-Chloro-3-trifluoromethyldiazirine, 0593 Diazirine, 0405... 

Brunner et al. (1980) have reported on the properties of a new class of aryl diazirines, the 3-aryl-3-trifluoromethyldiazirines. Besides forming a class of the most attractive photoactivatable reagents available, these molecules may be made in far higher yield than the corresponding 3-H-diazirines. The route used, which incidentally fails with the 3-H-com-pounds (Smith and Knowles, 1975), is shown in Fig. 3.24. Two drawbacks are the large number of steps involved and the difficulty of preparing... 

Alkyl-3-fluoro-3Zf-diazirines have become more readily available since the exchange of halogen in 3-alkyl-3-halo(chloro or bromo)diazirines by fluoride was developed" (for mechanistic consideration of this process, see refs 49 and 50, for 3-bromo-3-trifluoromethyldiazirine, see ref 47). Until now only a few 1-alkyl-1-fluorocyclopropanes la and Ib have been prepared by this method (see Houben-Weyl, Vol. E19b, p 1028). 

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