N,N"-(1,3-Propanediylidine)bis 1,2-Benzenediaminato Nickel(II) Complexes: Intermediates in the Template Synthesis of Dibenzotetra 14 Annulenes
Cutler, A.R., Alleyne, C.S., and David Dolphin
[NiL]PF6 [HL = 2-H2N-4-R-5-R1C6H2N:C(R2)CH2C(R3):NC6H2-2-NH2-4-R-5-R1; R = R1 = R2 = H, R3 = H, CH3; R = R1 = H, R2 = CH3, R3 = CH3, C6H5; R = R1 = R2 = R3 = CH3; R = H or CH3, R1 = CH3 or H, respectively, R2 = R3 = H] were prepared and characterized. The complexes were prepared in situ by condensation of a β-diketone or acetal with an appropriate o-phenylenediamine in the presence of a Ni(II) salt. 1,5-Benzenediazepinium salts were also used as light precursors in preparing the complexes. Evidence is presented which indicates that monoanils participate as intermediates in the metal template condensation of these diamines with β-diketones.