Platinum(II) complexes of 2-alkoxy-dibenzo[c.e][1,2]oxaphosphorines

2-Alkoxy-dibenzo[c.e][1,2]oxaphosphorines were prepared by the reaction of chloro-dibenzooxaphosphorine with alcohols and were converted to the cyclic phosphonates by oxidation and to the corresponding phosphonous boranes by reaction with borane-dimethylsulfide. Interaction of the alkoxy-dibenzooxaphosphorines with dichlorodibenzonitrileplatinum led to bis(dibenzooxaphosphorino)dichloroplatinum complexes exhibiting the P-ligands in the cis disposition. Relative energetics for the prepared cis and the theoretically possible trans isomers of the complexes along with their stereostructures were investigated by quantum chemical calculations.