Silver complexes amidines

Other amidinate anions normally form dinuclear copper(I) complexes with bridging amidinate ligands, although tetracopper(l) complexes have also been reported Silver(1) forms dimeric complexes with functionalized N,N -... 

Theoretical studies by Pyykkb in 1998 for [M2(NHCHNH)2] systems, M=Cu, Ag, and Au, predicted the M-M distances at the MP2 level [8]. Experimentally, systems containing amidinate ligands were known with Cu and Ag but unknown with Au. The results for the models containing silver and copper are close to the X-ray structures of [M2(ArNC(H)NAr)2], Ar=C6H4-4-Me and M=Ag, Cu. The Ag-Ag distance is 2.705 and 2.712 A and the Cu-Cu distance is 2.497 and 2.528 A at the experimental and theoretical level. Table 1.1. The hypothetical dinuclear gold(I) amidinate compound was calculated to have an Au-Au distance at the MP2 level of 2.728 A [8]. The dinuclear gold(I) amidinate complex now known proves the predicted Au-Au distance to be rather good. 

Silver dinuclear and trinuclear amidinate complexes are also known. Also, bis-(amidinate) complexes are obtained by direct metallation of amidines. ... 

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