Carbon-13 nuclear magnetic resonance spectra of some polyphosphines with ethane bridges between trivalent phosphorus atoms

Abstract

H and C6H5), and P(CH,CH,PH,), have been examined. Replacement of alkyls by hydrogen in R, P units consistently raises the 13C n.m.r. chemical shifts (i.e., lowers the 6 values) of CH, groups attached to this phosphorus. The spin-spin splittings in the 13C n.m.r. spectra by the phosphorus atoms in (C6H5)2PCH2CH,P(C6H5), and C6H5P[CH,CHzP-,], must be analysed as second-order ABX systems whereas those in the remaining polyphosphines can be analysed as first-order AMX systems. The range of significant phosphorus-carbon coupling in these compounds is limited to three bonds. In most cases, the coupling constants lJ(C-P) and 2J(C-P) have nearly equal magnitudes but opposite signs. However, direct bonding of hydrogen to a trivalent phosphorus atom appears to decrease markedly its 12J(C-P)I while having much less effect on its IIJ(C-P)I. This indicates that substitution on phosphorus of alkyls or aryls by hydrogens has a major effect on the conformation of the PCH,CH,P chain. 30602, U.S.A.RECENTLY Manii reported 13C n.m.r. chemical shifts and carbon-phosphorus coupling constants on an extensive series of tertiary phosphines. We were interested

Iron(0) and ruthenium(0) complexes with tridentate phosphonite ligands and their potential for ketene formation from methyl iodide, CO and a base

“…In general, carbonyl complexes of iron (Fe(CO) 5 , Fe 2 (CO) 9 and Fe 3 (CO) 12 ) react with monodentate phosphine ligands to give mixtures of the mono-and disubstituted derivatives [Fe(CO) 4 L] and [Fe(CO) 3 L 2 ] [48,49]. This behaviour is expected to result from the intermediary [Fe(CO) 4 ] [50,51].…”

“…The polyphosphines containing terminal alkoxy groups provide chelating ligands with stronger p-accepting properties than polyphosphines containing terminal alkyl groups [2][3][4], owing to the greater electronegativity of the alkoxy substituents [5]. Essentially two methods have been applied to introduce alkoxy substituents on a phosphorus atom: the alcoholysis of aminophosphine derivatives [6][7][8][9][10] or the reaction of chlorophosphine derivatives with an alcohol in the presence of a tertiary amine base [11][12][13][14][15].…”

“…13 C{ 1 H} NMR (CD 2 Cl 2 , 298 K): 19.7 (m, -CH 2 CH 2 CH 2 -), 26.2 (dt, J CP = 26.2, 5.2 Hz,-CH 2 CH 2 CH 2 -P(C 6 H 11 )), 26.9 (s, cyclohexyl C para), 28.1 (d, 3 J CP = 11.2 Hz, cyclohexyl C meta), 28.6 (d, 2 J CP = 12 6. Hz, cyclohexyl C ortho), 33.8 (dt, J CP = 4.6, 25.1 Hz, -CH 2 CH 2 CH 2 -P(OCH 3 ) 2 ), 38.6 (d, 1 J CP = 16 4. Hz, cyclohexyl C ipso), 51.9 and 52.8 (m, -P(OCH 3 ) 2 ), 215.8 (q, 2 J CP = 17.1 Hz, CO)).…”

Nucleophilic diaddition of secondary phosphine sulfides to acetylene and methylacetylene

“…Earlier, in Ref. 20 dealt with the study of polyphosphines with the ethylene bridge, it has been reported that the signals for the 13 C carbon atoms of the PCH 2 CH 2 P group are triplets and this was the basis for the suggestion on the equivalence of the 1 J C,P and 2 J C,P spin spin coupling constant values in such a fragment. Taking into account the complex char acter of the multiplets observed in the 13 C NMR spectra, we simulated the 13 C NMR spectrum using the gNMR 5.0 program, which allows one to perform the iteration selec tion of spectral parameters (Fig.…”

Synthesis and characterization of single-source molecular precursors to binary metal sulphides: bis(diethyldithiocarbamato)M(II)trialkylphosphine (M = Zn and Cd) adducts

“…Simulation of the variable temperature 11 3 Cd NMR spectra yielded another set of rate constants (see Figure 2) as a function of temperature which were comparison, the 3-bond P-P coupling constant for the heterobimetallic compound through the P-CH 2 CH 2 -P' chain is similar to the value reported for R 2 PCH 2 CH 2 PR' 2 species where R and R' are different. 43 46 The presence of the 3-bond P-P coupling is consistent The structural integrity of the mixed metal species, 7 was investigated in the solid state by X-ray powder diffraction. The X-ray powder diffraction data for the heterobimetallic species 7 did not match that of either the homobimetallic species 5 or 6.…”