Carbanionic character of decafluorobenzhydryl bromide. Behaviour towards nucleophiles

Decafluorobenzhydryl bromide (1) reacts with nucleophiles to give 1,1,2,2-tetrakis(pentafluorophenyl)-ethane (2) as the predominant product; there is no evidence of products derived from initial nucleophilic displacement on the carbon of (1).