The use of 1,2-dipiperidinoacetylene for the preparation of monometallic diaminoacetylene and homo- or heterobimetallic diaminodicarbene ruthenium(II) complexes

摘要: The reaction of the ynediamine 1,2-dipiperidinoacetylene (1) with [(η2-COE)Cr(CO)5], [(THF)W(CO)5] and [RuCl2(η6-cymene)]2 afforded homobimetallic complexes 2a, 2b 3, in which diaminoacetylene 1 acts as a bis(aminocarbene) ligand by bridging two complex fragments Cr(CO)5 (in 2a), W(CO)5 2b) RuCl2(η6-cymene) 3). [RuCl2(PPh3)3] gave trans-[(1)RuCl(PPh3)2]Cl, [4]Cl, alkyne coordinates 4-electron donor ligand. cation 4 represents rare example square-planar Ru(II) low-spin ground state (S = 0), its stability can be ascribed to strong alkyne-metal π-interaction confirmed DFT calculations. Treatment one or equivalents NaBPh4 acetonitrile [4]BPh4 dicationic [(1)Ru(PPh3)2(CH3CN)2](BPh4)2, [5](BPh4)2. [4]Cl used for preparation heterobimetallic Ru-Pd [(MeCN)2PdCl2], resulting formation bimetallic 6 tetrametallic 7.