cis-Bis[(1-adamantylmethyl)amine-κN]dichloridoplatinum(II) N,N-dimethylformamide solvate

The asymmetric unit of the title compound {systematic name: cis-dichloridobis[(3,7-dimethylbicyclo[3.3.1]non-1-ylmethyl)amine-κN]platinum(II) N,N-dimethylformamide solvate}, [PtCl2(C11H19N)2]·C3H7NO, consists of two metrically similar Pt complexes and two dimethylformamide solvent molecules. Each PtII center is coordinated by the amine groups of two (1-adamantylmethyl)amine ligands and two Cl atoms in a cis-square-planar arrangement. The PtII centers lie slightly outside [0.031 (4) and 0.038 (4) Å] the coordination planes. The N—Pt—N and Cl—Pt—Cl angles [92.1 (4)–92.30 (11)°] are slightly more open than the N—Pt—Cl angles [87.3 (3)–88.3 (3)°]. N—H⋯O and N—H⋯Cl intermolecular hydrogen bonds are observed, forming two discrete pairs of complexes and solvent molecules.


Related literature
For the antiviral and antitumor activity of Pt complexes with polycyclic cages such as adamantamine, see: Hay et al. (1985); Ho et al. (1972); Widell et al. (1986). The synthesis and spectroscopic characterization of the title compound is described by Rochon et al. (1993).
The synthesis and the spectroscopic study of Pt II compounds with adamantanamine derivatives have been reported (Rochon et al., 1993).
In the title compound (one of the Pt complex is shown in Fig. 1), the Pt metal center exhibits a cis square-planar geometry formed by two amine groups from (1-adamantylmethyl)amine and two Cl atoms. The Pt centers are slightly outside [0.031 (4) and 0.038 (4) Å] the N 2 Cl 2 planes. The bulky adamantane cycles slightly open the N-Pt-N angles The asymmetric unit of the title compound is described as two crystallographically independent Pt complexes and two dimethylformamide (DMF) solvent molecules linked by N-H···O hydrogen bonds (Fig. 2) between the amine groups and the O atoms from the DMF molecules. N-H···Cl hydrogen bonds between the amine groups and Cl atoms from symmetry equivalent complexes are also observed, forming discrete pairs of complexes and solvent molecules (Fig. 3).

S2. Experimental
One mmol of K 2 [PtCl 4 ] and 2 mmol of (1-adamantylmethyl)amine were heated in a DMF solution at 80°C for 3 h. The solution was concentrated, cooled to 0°C and the KCl was filtered off. The mixture was evaporated to dryness and the residue washed with ether, acetone and then with water. After drying, the residue was washed with ether and dried. Yield 68%,325,Raman 334,195 Pt NMR -2213 p.p.m. The crystals were recrystalized in DMF for crystallographic studies.

S3. Refinement
H atoms were placed at calculated positions (C-H = 0.95-1.00 Å, N-H = 0.92 Å) and were allowed to ride on their parent atoms, with U iso (H) = 1.2U eq (C,N) for the CH, CH 2 and NH 2 groups and U iso (H) = 1.5U eq (C) for the CH 3 groups.