Dinuclear zinc(II) complexes of a Robson macrocycle

Abstract

Dinuclear zinc(II) complexes of the Robson macrocycle H₂L, derived from the cyclocondensation of 2,6-diformyl-4-methylphenol and propane-1,3-diamine have been synthesised and their crystal structures determined. The compound Zn₂(L)(ClO₄)₂·2H₂O crystallises in the monoclinic space group P2₁/a(C⁵_2h no. 14) with a= 14.755(15), b= 12.348(12), c= 16.825(17)Å, β= 105.80(3)° and Z= 4. The crystal structure consists of two independent pairs of dinuclear zinc complexes (molecules 1 and 2). Molecule 1 contains two six-co-ordinate zinc(II) with an intermetallic distance of 3.166 Å, and molecule 2 has two five-co-ordinate zinc(II) with a Zn ⋯ Zn distance of 3.177 Å. The compound [Zn₂(L)(N₃)₂] crystallises in the monoclinic space group P2₁/c(C⁵_2h′ no 14) with a= 7.733(5), b= 11.865(6), c= 14.466(4)Å, β= 90.86(4)° and Z= 2. The two zinc atoms are five-co-ordinate and are separated by 3.333 Å.