title: Regiochemical substituent switching of spin states in aryl(trifluoromethyl)carbenes.
abstract: Although aryl(trifluoromethyl)diazirines have achieved great popularity in photoaffinity labeling applications, the properties of the corresponding carbenes have not been as widely explored. Here, low-temperature matrix-isolation spectroscopy and reactivity studies indicate that in contrast to m-methoxyphenyl(trifluoromethyl)carbene and most known aryl(CF(3))carbenes, the para isomer is a ground-state singlet rather than triplet. DFT calculations support these results as well as the notion that the p-CH(3)O group stabilizes the singlet carbene via resonance. These results may have relevance to the wide range of substituted aryl(CF(3))diazirines in photoaffinity applications.
authors: Department of Chemistry, University of Nevada, Reno, Nevada 89557, USA.
authors: Myoung-Geun
authors: MG
authors: Song
authors: Robert S
authors: RS
authors: Sheridan