Conformational analysis of coordination compounds. ix: H N.M.R. Study of diamagnetic complexes of (r)-1-phenylethane-1, 2-diamine

The conformational analyses of the complexes [Co(CN)4L]-, [Co(NH3)4L]3+, [Mo(CO)4L], and [PtL2]2+, where L is (R)-l-phenylethane-1, 2-diamine, have been carried out by a method based on the vicinal proton coupling constants of the CHCH2 fragment. In the three octahedral complexes, the phenyl showed a similar preference for the equatorial orientation with nλ. values of 0·87 ± 0·05, 0·84+0·11, and 0·77±0·01, respectively. For the bis(diamine)platinum(II) complex, the λλ. and δλ configurations were found to be equally populated, with the δδ configuration 3·4kJ mol-1 less favoured