Photolysis of 3-(2, 2, 2-triphenylethoxy)-3-chlorodiazirine gives 2, 2, 2- triphenylethoxychlorocarbene which fragments with 1, 2-phenyl migration and loss of CO and Cl-to yield the 1, 1, 2-triphenylethyl cation and thence 1, 1, 2-triphenylethene by proton loss. However, ps and fs laser flash photolysis provides evidence that up to 25% of the alkene product stems from carbocation that arises directly from excited diazirine rather ...