Absolute configuration and crystal structure of (+)- cis-dichloro[( S)-1-butene][( S)-α-methylbenzylamine]platinum(II)

Abstract

The absolute configuration and the crystal structure of (+)- cis-dichloro-[( S)-1-butene][( S)-α-methylbenzylamine]platinum(II) has been elucidated by single-crystal X-ray analysis. The crystals belong to the orthorombic system, space group P2 12 12 1, with a = 17.28 », b = 13.08 », c = 6.52 » and four molecules per unit cell. Intensity measurements were carried out by automated counter techniques (Mo- K a ). The structure was solved by Patterson and Fourier syntheses. The final conventional R value for 1108 independent non-zero reflections was 0.042 (0.058 if 250 reflections below the limit of detectability are taken into account). The ligands lie in the square-planar arrangement around the platinum atom. The olefin double bond deviates by 11° from the ideal arrangement having the CC bond perpendicular to the square of coordination. The absolute configurations of the two asymmetric centers in the molecule have been determined and are compared with the chemical and physical data available for the complex.