Palladium(II) Schiff base complexes derived from allylamine and vinylaniline

Abstract

Condensation of salicylaldehyde (2-HOC6H4C(O)H) with allylamine afforded the unsaturated salicylaldimine, 2-HOC6H 4C(H)=NCH2CH=CH2. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or Na2PdCl4 afforded complexes of the type PdL2, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex [trans-(2-OC6H4C(H)=NCH2CH=CH2) 2Pd] (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group P21/n, a = 14.0005(9) Å, b = 7.2964(5) Å, c = 17.5103(12) Å, β = 100.189(1)°, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of [trans-(2-HOC6H 4C(H)=N-4-C6H4CH=CH2)2Pd] (4) were monoclinic, space group P21/c, a = 13.7710(14) Å, b = 11.0348(11) Å, c = 7.8192(8) Å, β = 98.817(2)°, Z = 2.