Difluoromethyl triflate

In order to test this effect, difluoromethyl perfluoroalkanesulfonates have been synthesized and investigated. Difluoromethyl triflate was synthesized earlier from the insertion of difluorocarbene, generated by photolysis of difluorodiazirine into the O—H bond of triflic acid114 (equation 94). By using HCF2S03H as a difluorocarbene precursor, difluoromethyl perfluoroalkanesulfonate can be obtained in 30-50% yields115 (equation 95). 

Indeed, metallation of diethyl difluoromethyl phosphonate affords an anion. This species can displace a primary triflate in position or add onto an aldehyde (in... 

The reaction of difluoromethyl sulfonates with KF is ca 40 times slower than that of methyl triflate. All these results indicate that the shielding effect caused by the two fluorine atoms in the difluoromethoxy carbon of the difluoromethyl sulfonates to some extent prevents the nucleophilic attack on this carbon, although due to the presence of a hydrogen atom the shielding is not as complete as in perfluoroalkanesulfonates117. 

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