19298-01-2Relevant academic research and scientific papers
Preparation and Properties of Bisdinickel(+1) Ion, a Novel Unsymmetrical Thiolate-bridged Complex
Pfeiffer, Ernst,Pasquier, Maurice L.,Marty, Werner
, p. 654 - 663 (2007/10/02)
The title cation( =Ni2L31+ ) is formed in a variety of reactions (Schemes 1 and 2) in systems containing Ni2+ and (2-thiolatoethyl)-diphenylphosphine ( =L- ) in the absence of coordinating anions at Ni2+/L- ratios >0.5 in apolar or moderately polar media.Solid ClO4 and BPh4 have been isolated.Job's plots confirm the Ni2L3+-stoichiometry in solution. 31P-NMR data are consistent with >/= 97 percent Ni2L3+ (vs. 2+) at equilibrium and support the suggested configuration (Fig.2).The equilibrium between NiL2 + NiL2Br2 and Ni2L3+ + Br- varies with the solvent composition in CH2Cl2/EtOH mixtures.The rate of formation of Ni2L2Br2 from Ni2L3+ and bromide (in high excess) in CH2Cl2 is first-order in +>tot but depends on the ratio tot/tot, even at a high excess of bromide.This is interpreted by efficient competition in ion-aggregate formation between the small perchlorate concentration introduced as the counterion of Ni2L3+, and the large excess of bromide.
