Regiochemistry of the Coupling of Aryl Radicals with Nucleophiles Derived from the Naphthyl System. Experimental and Theoretical Studies

Article abstract of DOI:10.1021/jo00002a019

We here report the photostimulated reaction of unactived aromatic halides with ambident nucleophiles derived from the naphthyl system such as 1- and 2-naphthylamide, 2-naphthoxide, 2-naphthalenethiolate, and 2 naphthaleneselenate ions, by the S_RN1 mechanism of nucleophilic substitution.According to our experimental results, C-arylation in position 1 of the naphthyl moiety is the only reaction observed with 2-naphthoxide ions and it is favored over N-arylation with 1- and 2-naphthylamide ions.Heteroatom arylation is preferred over C-arylation with 2-naphthalenethiolate ions while it is the only observed reaction with 2-naphthaleneselenate ions.A theoretical study was carried out to explain the regiochemistry of the system.In competition experiments, 2-naphthalenethiolate ions proved to be 1.8 +/- 0.2 times more reactive than 2-naphthoxide ions for C-substitution toward p-anisyl radicals in liquid ammonia.