A convenient synthesis of 8-[4-[3(trifluoromethyl)diazirinyl]-9-octade
cenoic acid (13) for photoaffinity labeling is described. Photochemica
l experiments on 13 and its precursor 11 in ethanol solution as well a
s in an argon matrix at 12 K demonstrate the formation of diazo compou
nds and ultimately carbene-derived products.