121379-07-5Relevant academic research and scientific papers
The synthesis, characterization, and some reactions of phosphonium thiolates and selenolates: the X-ray crystal structure of tetraphenylphosphonium 2,4,6-trimethylbenzenethiolate
Ball, Joanne M.,Boorman, P. Michael,Fait, James F.,Hinman, A. Scott,Lundmark, Penelope J.
, p. 751 - 758 (2007/10/02)
Synthetic methods for the preparation of PPh4, PPN, and PPh4 (Ar= aryl; PPN= bis(triphenylphosphyne)iminium)salts are described, and 1H NMR, infrared, and 77Se NMR spectroscopic characterization is given.The X-ray crystal stucture of 4> (mes = 2,4,6-trimethylbenzene) was carried out: space group P1, a=9.946(3) Angstroem, b=10.100(2) Angstroem, c=14.874(3) Angstroem, α=70.19(2) deg, β=69.13(2) deg, γ=82.54(2) deg, Z=2, R=0.100, Rw==0,074.The structure establishes the ionic nature of this compound in the solid state, and conductance measurements in acetonitrile are consistent with 1:1 electrolite behaviour.It is shown, however, that solutions of the thiolates are quite sensitive to hydrolysis to the thiol, and also the strong nucleophilicity of the thiolate and selenolate anions enables them to react wiht halocarbon solvents.The solenolate solutions are extremely sensitive to oxidation to the deselenide, which limited their study.Cyclic voltammetry on selecte thiolatesalts shows that impurities quickly develop even in acetonitrile solvent, but comparisons with the voltammograms of thiols and disulphides confirm the assignment of an irreversible oxidation wave at ca.-0.3 V (vs.Ag/AgNO3, 0.01 M) to the process: 2SR- --> R2S2 + 2e-.The potential at which this reaction occurs is related to the degree of substitution of the phenyl ring of the SAr- ion.Key words: phosphonium thiolates, phosphonium selenolates, tetraphenylphosphonium 2,4,6-trimethylbenzene thiolate.
