CARBON-NITROGEN BOND FORMATION BY REDUCTIVE ELIMINATION FROM NICKEL(II) AMIDO ALKYL COMPLEXES

Reaction of the azametallacyclohexane complex [(bpy)Ni{N(Tol)(CH2)(4)} ] (1) with diacetylferrocenium tetrafluoroborate, O-2, or I-2 induces N-C reductive elimination, giving high yields of N-p-tolylpyrrolidine (2) upon, chromatographic workup. Reaction of[(bpy)Ni(CH(2)CMe(2)-o-C6 H4)] (3) with N(3)Ph gives the azametallacycle [(bpy)Ni(NPh-o-C(6)H(4) CMe(2)CH(2))] (4), which reacts with CO to give the Lactam PhNC(O)CH(2 )CMe(2)-o-C6H4 (5) and with HCl to give 2-tert-butyl-N-phenylaniline. Oxidation of 4 with [(AcCPFe+], I-2, or O-2 results in N-C reductive e limination and affords high yields of the indoline PhN(CH(2)CMe(2)-o-C 6H4) (6). The azametallacycle 4 is also thermally unstable with respec t to C,N-reductive elimination to give 6. Significantly lower yields o f products resulting from N-C reductive elimination, are realized when acyclic alkylnickel amides are oxidized. Thus, N,N-dimethyl-p-toluidi ne (8) is produced by the reaction of[(AcCPFe+], I-2, or O-2 with [(bp y)Ni{N(Tol)(Me)}(Me)] (7), [(bpy)Ni{N(Ph)(Et)}(Et)] (9) reacts with I- 2 to afford both N,N-diethylaniline (10) and N-ethylaniline (11) compe titively, and [(bpy)Ni{N(Tol)(i-Bu)}(i-Bu)] (12) reacts with I-2 to gi ve, primarily, N-isobutyl-p-toluidine (14), with smaller amounts of N, N-diisobutyL-p-toluidine (13).