Diphenyldiazomethane, 9-diazofluorene and other diazo substituted hydrocarbons

4 DIPHENYLDIAZOMETHANE, 9-DIAZOFLUORENE AND OTHER DIAZO SUBSTITUTED HYDROCARBONS 

Detailed studies of the solvolysis of diphenyldiazomethane in ethanol Ph2CN2 + EtOH = Ph2CHOEt + N2 

In the presence of picric acid, the reaction products were the same, but general acid catalysis could be observed. The solvent isotope effect was determined using a mixture of 82.5 % ethanol and 17.5 % water. If 38 % of the mobile (O-bonded) hydrogen of the solvent was replaced by deuterium the reaction rate was decreased by a factor of 1.45. Linear extrapolation to 100% deuteration led to an approximate result of kH/kD 2.2. Similar experiments referring to general catalysis and solvent isotope effects have been done for the ethanolysis of 9-diazo-fluorene, and similar results have been obtained [215]. 

In the reaction of 9-diazofluorene in 93.8% ethanol—water, the catalytic coefficient, kH, is approximately the same for perchloric acid and hydrochloric acid at low concentrations, though some 9-chlorofluorene is formed in the presence of hydrochloric acid. If the concentration of the strong acid is increased fcH rises more in perchloric acid solutions than in hydrochloric acid solutions. The product ratio of 9-chlorofluorene always remains below 50 %, and its dependence on the chloride ion concentration is small [215]. 

The experimental findings support a mechanism with rate-determining proton transfer for the ethanolysis reactions of diphenyldiazomethane and 

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