135624-53-2Relevant academic research and scientific papers
Die Carbonylchrom-, Carbonylmolybdaen- und Carbonylwolfram-Komplexe der Unsymmetrisch Substituierten Phosphinoschwefeldiimide tBu2P(NSN)PPh2 und tBu2P(NSN)P(tBu)Ph. 1H, 13C und 31P NMR-Spektroskopische Charakterisierung
Herberhold, Max,Frank, Stefan M.,Wrackmeyer, Bernd
, p. 159 - 173 (2007/10/02)
In addition to the carbonylmetal complexes of bis(di-tert-butylphosphino) sulfur diimide, tBu2P(NSN)PtBu2 (1), carbonylmetal derivatives of the unsymmetrically substituted phosphino sulfur diimides tBu2P(NSN)PPh2 (2) and tBu2P(NSN)P(tBu)Ph (3) have been prepared and characterized by NMR, IR and mass spectroscopy.In the presence of THF-stabilized pentacarbonylmetal 16-electron complex fragments, (M = Cr (a), Mo (b), W (c)), 2 and 3 react to give binuclear complexes tBu2P(NSN)P(R)Ph (R = Ph (4a-c), tBu (5a-c).The norbornadiene compounds M(CO)4(nor-C7H8) can be used to prepare chelate complexes of 2 and 3 with 14-electron complex fragments, , i.e. tBu2P(NSN)P(R)Ph (R = Ph (6a-c), tBu (7a-c).The structures of the new complexes were established on the basis of their 1H, 13C and 31P NMR spectra.As a result of the different substitution at the two phosphorus centers in 2 and 3, a variety of NMR parameters can be obtained which are not easily accessible for symmetrically substituted phosphino sulfur diimides such as 1 and their metal complexes.On the basis of the 31P NMR spectra it is assumed that the binuclear complexes 4a-c and 5a-c are fluxional molecules in solution and undergo configurational Z/EE/Z interconversion; no significant signal broadening or splitting could be observed down to -90 deg C in the cases of S(N-PtBu2)2 and tBu2P(NSN)PPh2 (4b).Hahn-spin-echo experiments were used to determine coupling constants 1J(31P,15N).The 13C-NMR spectra of the chiral chelate complexes tBu2P(NSN)P(tBu)Ph (7a-c) are temperature-dependent, indicating restricted rotation of the phenyl substituent around the P-C bond (ΔG = 57.1 +/- 1 kJ/mol in 7c).
