2-Amino-2-oxazoline and trialkylisourea Pt(II) complexes derived from organocyanamides

In the di(organocyanamide) complexes trans-[PtCl2(NCNR2)2](R = Me 1a, Et 1b), prepared by reaction of PtCl2 with the appropriate NCNR2, the cyanamide ligands, activated by coordination, undergo an unprecedented nucleophilic addition, at room temperature, of an haloalcohol (ClCH2CH2OH/LiBun) or of an alcohol (MeOH) to give the corresponding 2-amino-2-oxazoline cis-[PtCl2{ N=C(OCH2C H2) NR2}2](R = Me 2a, Et 2b) or trialkylisourea trans-[PtCl2{NH=C(OMe)NR2}2](R = Me 3a, Et 3b) complexes. The X-ray crystal structure of 2b is also reported, indicating a (pi)-bond delocalization along the N-C-N group of the aminooxazoline ligands.