151175-53-0Relevant academic research and scientific papers
Heterodifunctional ligands derived from monooxidized bis(phosphino)amines. Synthesis and transition metal (molybdenum(0), tungsten(0), rhodium(I), palladium(II), and platinum(II)) complexes of (diphenylphosphino)(diphenylphosphinothioyl)- and (diphenylphosphino)(diphenylphosphinoselenoyl)phenylamine, Ph2PN(Ph)P(E)Ph2 (E = S, Se). ...
Balakrishna, Maravanji S.,Klein, Rita,Uhlenbrock, Stephen,Pinkerton, A. Alan,Cavell, Ronald G.
, p. 5676 - 5681 (2008/10/08)
Full title: Heterodifunctional ligands derived from monooxidized bis(phosphino)amines. Synthesis and transition metal (molybdenum(0), tungsten(0), rhodium(I), palladium(II), and platinum(II)) complexes of (diphenylphosphino)(diphenylphosphinothioyl)- and (diphenylphosphino)(diphenylphosphinoselenoyl)phenylamine, Ph2PN(Ph)P(E)Ph2 (E = S, Se). Crystal and molecular structure of the Pt(II) complex [Cl2PtPPh2N(Ph)P(S)Ph2]·H2O. Bis(diphenylphosphino)phenylamine can be selectively oxidized by S or Se in toluene or hexane solvents to the monooxidized thioyl or selenoyl products Ph2PN(Ph)PPh2=E, (E = S, Se). These compounds act as bidentate chelate ligands toward metal complexes forming (CO)4M(LL) (M = Mo, W), CO(Cl)Rh(LL), and Cl2M(LL), (M = Pt, Pd) where (LL) is the thioyl or selenoyl derivative of the aminobis(phosphine). IR and NMR data are given for all complexes. The carbonyl infrared stretching frequencies show that the chelates form with the phosphine cis to any CO which is present. The 31P NMR of all complexes consists of two doublets except for the Rh complexes wherein the Rh spin also couples to phosphorus to produce two doublets of doublets. The 2JPP values range from 56 to 112 Hz. 1JPSe, coupling provide valuable assistance for the assignment of the phosphorus resonances which range widely from 55 to 126 ppm for PIII and from 60 to 80 ppm for the PV case. Assignment of PIII and PV signals, which invert relative shift positions on occasion, is aided by the analysis of appropriate spin satellites arising from the substituents. It is concluded that coordination shifts for PIII are always positive, ranging from 22 ppm for PtII complexes to 70 ppm for RhI complexes. Coordination shifts for PV centers are much smaller, e.g. 0-12 ppm, and in some cases the coordination shifts for the PV centers are negative versus the free ligand. A crystal structure of the Pt complex [Cl2PtPPh2N(Ph)P(S)Ph2]·H2O (at 25°C, monoclinic P21/c a = 9.117(1) A?, b = 18.783(3) A?, c = 17.288(2) A?, β = 92.16(1)°, V = 2959(1) A?3, Z = 4) showed the chelate structure comprising a relatively strain-free five membered ring containing a trigonal planar N in the backbone. The short PV(1)-N (1.674(7) A?) bond length is similar to a phosphazene bond length and indicative of multiple bond character. Although the complex could only be crystallized with 1 mol of H2O, there was no evidence for unusual interaction of this water molecule with the complex. The PIII-N bond length (1.737(7) A?) is similar to the usual PIII-N distances. The geometry suggests significant delocalization from the nitrogen bridge into the backbone of the chelate.
