Group 6 homo-bimetallic carbonyl complexes containing polydentate phosphine ligands

Fac and mer dppe-substituted Fischer carbene complexes of chromium: X-ray, DFT and electrochemical study

“…On comparing chemical shift values for the cis and trans isomers of monophosphine substituted carbene complexes [41], the two peaks of the mer isomer could be assigned. The coupling constants observed for 1 and 2 for the 2 J PP couplings were smaller in general compared to literature reports [42], but comparable. It is observed that the phosphorous resonance is shifted more upfield when the phosphorous atom is found trans to a carbene ligand (P1) compared to the resonance when the phosphorous atom is found trans to a carbonyl ligand (P2) (atom numbering refer to Figures 3-5 and 7).…”

A Novel Reactivity Mode for Metal-Activated Dialkylcyanamide Species: Addition ofN,N′-Diphenylguanidine to acis-(R2NCN)2PtIICenter Giving an Eight-Membered Chelated Platinaguanidine

“…It is worth mentioning that five- and six-membered metal chelate rings are the most conventional ring systems in coordination chemistry insofar as they exhibit exceptional stablity , (for general consideration of the chelate effect, see refs − ). However, seven-, − eight- (in particular, having N ∩ N, ,,− P ∩ P, ,− S ∩ S, , Se ∩ Se, O ∩ O, − P ∩ O, and C ∩ O donor centers), − nine-, ,, ten-, eleven-, and twelve-membered and also complexes with trans-spanned ligands and large metallamacrocycles ,− , are also known, albeit they are still unusual rather than common.…”