Cleavage of α-nitroketones by platinum(II) and platinum(0) and formation of platinum(II) complexes containing fulminato- and carboxylato-groups
Abstract
Reaction of the complex [(PPh3)2PtCl2] with TlIsalts of 2-nitroacetophenone (PhCOCH2NO2), nitroacetone (MeCOCH2NO2), and 1-nitrobutan-2-one (MeCH2COCH2NO2)(molar ratio 1 : 1 to 1 : 2) in benzene occurs with breaking of the carbon–carbon bond internal to the α-nitroketonic group, the fragments produced then co-ordinating to PtII as fulminato- and carboxylato-groups. The complexes isolated have formulae [(PPh3)2PtCl(CNO)], [(PPh3)2Pt(OCOR)(CNO)], and [(PPh3)2PtCl(OCOR)](R = Me, Et, or Ph). Reaction of the complex [Pt(PPh3)4] and 2-nitroacetophenone in benzene–ethanol–water (4 : 1 : 1) has also been studied and the complexes [(PPh3)2Pt-(OCOPh)(CNO)] and [(PPh3)2Pt(CNO)2] isolated. I.r. spectra indicate that isomerization of the fulminato-groups to isocyanato-groups occurs.