Reaction of 1-Bromoadamantane with Diphenylphosphide and Diphenylarsenide Ions by the SRN1 Mechanism. Facile Nucleophilic Substitution at the Bridgehead Position

Article abstract of DOI:10.1021/jo00145a010

The photostimulated reaction of 1-bromoadamantane (1) with diphenylphosphide (2) and diphenylarsenide (6) ions in liquid ammonia afforded good yields of the substitution products, together with small amounts of adamantane (4) and 1,1'-biadamantyl (5) as byproducts.The reaction of 1 with 2 in the dark did not occur, but stimulation with solvated electrons gives a small amount of the substitution product and 5, with a large amount of 4.The photostimulated reaction of 1 with 2 is inhibited by p-dinitrobenzene and di-tert-butyl nitroxide.All these results suggest that these reactions occur by the S_RN1 mechanism of substitution, where radical and radical anions are intermediates.