A New Approach to α,α-Difluoro-Functionalized Esters

Article abstract of DOI:10.1021/jo00017a026

The addition reaction of iododifluoroacetates to alkenes is initiated by copper powder (10-20 mol percent) at 50-60 deg C.Both terminal and internal alkenes give good yields of adducts.The reaction is also applicable to alkenes containing a variety of functional groups, such as epoxy, hydroxy, ketone, ester, and phosphonate moieties.This reaction can be carried out either neat or in solvents such as hexane, benzene, acetonitrile, DMF, DMSO, and HMPA and is suppressed by p-dinitrobenzene and di-tert-butyl nitroxide.A single electron transfer initiated radical mechanism isproposed.In the presence of nickel dichloride hexahydrate, reduction of the adducts with zinc in moist THF provides the corresponding α,α-difluoro esters in good yields.