Compartmental ligands. Part 7. The reactions of 1,2-diaminobenzene and cis-1,2-diaminocyclohexane with heptane-2,4,6-trione and 1-(o-hydroxyphenyl)butane-1,3-dione. The crystal structures of 1-(o-aminophenyl)-2,6-dimethyl-4-pyridone hemihydrate and {3,3′-(cis-1,2-cyclohexanediyldi-imino)bis[1-(o-hydroxyphenyl)but-2-enonato]-(N,N′,O1,O1′)}copper(II)

Abstract

The reaction of 1,2-diaminobenzene with heptane-2,4,6-trione yielded either the compound 2-(acetylmethyl)-4-methyl-3H-1,5-benzodiazepine or 1-(o-aminophenyl)-2,6-dimethyl-4-pyridone (5) depending upon the conditions used. The reaction of 1,2-diaminobenzene with 1-(o-hydroxyphenyl)butane-1,3-dione yielded a diazepine. In contrast the reaction of cis-1,2-diaminocyclohexane with heptane-2,4,6-trione yielded a tetramine macrocyclic compound, and with 1-(o-hydroxyphenyl)butane-1,3-dione afforded the compartmental Schiff base 3,3′-(cis-1,2-cyclohexanediyldi-imino)bis[1-(o-hydroxyphenyl)but-2-enone](10). The metal-complexing properties of this ligand are reported. Three-dimensional X-ray crystal-structure analyses have been carried out on compound (5) and on the mononuclear copper(II) derivative of (10), i.e. (12). Compound (5) has Z= 8 in a monoclinic cell with space group P2₁/c, and dimensions a= 14.984(1), b= 7.475(3), c= 21.173(1)Å, and β= 98.71(1)°; R= 0.0388 for 2 392 reflections. Complex (12) has Z= 4 in a triclinic cell with space group P, and dimensions a= 13.143(8), b= 14.279(8), c= 14.289(14)Å, α= 67.36(6), β= 71.18(7), and γ= 91.36(5)°; R= 0.0651 for 2 985 reflections. The structure shows the copper(II) to occupy the inner (N₂O₂) co-ordination site in an environment with a marked (ca. 14°) tetrahedral twist.