N,N-Diethylcarbamato tertiary phosphine complexes as precursors to carbonato and carbamoyl platinum(II) derivatives ‡

The complexes cis-Pt(O2CNEt2)2(PR3)2 (R = Ph, Et) and Pt(O2CNEt2)2(DPPE) [DPPE = 1,2-bis(diphenylphosphino)ethane] were prepared by the reaction of the corresponding phosphino-chloro complexes of platinum with Ag(O2CNEt2). The new N,N-diethylcarbamato complexes are excellent precursors for the high-yielding preparation of the corresponding carbonato derivatives Pt(CO3)(PR3)2 or Pt(CO3)(DPPE) by reaction with a stoichiometric amount of water. The carbamato complex cis-Pt(O2CNEt2)2(PPh3)2 reacts with CO producing the carbamoyl derivative cis-Pt[C(O)NEt2]2(PPh3)2. The chloro-carbamoyl complex, prepared by reacting cis-PtCl2(PPh3)2 with NHEt2 and CO, and recrystallized from toluene as the solvated species trans-PtCl[C(O)NEt2](PPh3)2·2 C6H5Me has been structurally characterized.