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By reaction of RP(O)Cl2 with RP(O)(OSiMe3)2, phosphonic anhydrides (RPO2)3 (R = tBu, 2-methylphenyl, 2,4,6-trimethylphenyl) 1a−c are conveniently obtained. In contrast to 1b and 1c, compound 1a is remarkably stable against protolysis. Intermediates of hydrolysis of 1a, namely tris(tert-butyl)triphosphonic acid (2) and bis(tert-butyl)diphosphonic acid (3), can also be isolated in good yield. The structures of 1−3 were determined mainly by NMR spectroscopy (1 H, 13C, 31P). Assuming an energetic preference for the chair conformations in solution, and considering the steric requirements of the bulky substituents R, configurations Ia (point group Cs, two R in equatorial positions) for 1a and b, and IIa (point group C3v, all R equatorial) for 1c are suggested. − Reaction of 1a with N-benzyloxycarbonylglycine (4) in methanol affords strong evidence that in the first step of peptide synthesis with (RPO2)3, a mixed anhydride of triphosphonic acid and the N-protected amino acid is formed. − The crystal structure of 1a (monoclinic, space group P21/n) widely corresponds to the suggested configuration Ia, but reveals an envelope conformation for the six-membered ring with a P3O2 plane in the crystal. In the crystal structure of the octahydrate of the disodium salt of 2 (monoclinic, space group P21/c), it can be seen that the polar end groups of the anions [tBu3P3O7]2− together with the water molecules and the Na+ cations, form hydrogen-bonded double-layers, strictly separated from each other by the non-polar tert-butyl groups of the anions.

The synthesis and the 31P-, 1H-, 13C- and 29Si-NMR spectra of some new Di(organylamino)-diorganylphosphonium bromides [R2P(NHR')2]Br 1 (R = iPr, Ph; R' = Me, Et, iPr) and of Iminophosphinic acid amides R2P(NR')(NHR') (R = Et, tBu, Ph; R' = SiMe3) 2 are reported. 1 and 2 can be converted into the Li-salts of ligands R2P(NR')2 − that are potential chelate ligands in metal complexes.

The structure of the gaseous long-lived radical cation generated upon electron ionization of trimethylphosphine oxide, (CH 3 ) 3 PO, has been investigated by using ion-molecule reactions in a Fourier transform ion cyclotron resonance mass spectrometer. A radical cation with the connectivity of trimethylphosphine oxide is expected to react by facile electron transfer with triethylamine, pyridine and dimethyl disulfide since all these reactions are highly exothermic. However, no electron transfer reactions were observed. Instead, the radical cation transfers a proton to triethylamine and to pyridine, i.e., acts as a Bronsted acid. Further, the radical cation abstracts CH 3 S from dimethyl disulfide and hence demonstrates behavior characteristic of a distonic ion with a carbon radical center. This reactivity is unprecedented for a radical cation such as (CH 3 ) 3 P + -O with the odd spin located at an oxygen atom. These experimental results indicate that the initially generated radical cation (CH 3 ) 3 P + -O undergoes unimolecular isomerization to (CH 3 ) 2 P + (OH)CH 2 within a millisecond time frame. Ab initio molecular orbital calculations carried out at the unrestricted second-order Moller-Plesset (UMP2/6-31G** + ZPVE) level of theory support this conclusion by predicting that (CH 3 ) 2 P + (OH)CH 2 lies 23 kcal mol −1 lower in energy than (CH 3 ) 3 P + -O. The energy barrier for unimolecular [1,3]-hydrogen atom migration in (CH 3 ) 3 P + -O is estimated to be 24 kcal mol −1 . This study demonstrates that the PO moiety provides a very strong driving force for hydrogen shifts in phosphorus containing radical cations.

Die Umsetzung einiger sterisch anspruchsvoller Trialkylphosphine L = PR2R′ (R = iPr, R′ = tBu; R = tBu, R′ = iPr, Me) mit NiX2 (X = Cl, Br) in Ethanol liefert infolge Beteiligung des Solvens statt der erwarteten Nichtelektrolyte [NiL2X2] tertiare Phosphoniumnickelate [HL][NiLX3]. Im Falle des weniger raumerfullenden PtBu2Me entstehen beide Komplextypen. [Ni(PtBu2Me)2Cl2] ist tetraedrisch und stellt somit eines der beiden bisher bekannten Beispiele fur paramagnetische Bis(trialkylphosphin)dihalogenonickel(II)-Komplexe dar. In Losungen dieser Verbindung existiert ein Gleichgewicht zwischen tetraedrischem (paramagnetischem) und planarem (diamagnetischem) Konformer. Vis-Spektren sowie Ergebnisse magnetischer Messungen und 1H- bzw. 31P-NMR-Untersuchungen werden mitgeteilt. [NiL2X2] or [HL][NiLX3] – Reaction of Sterically Demanding Trialkylphosphines L with NiX2 (X = Cl, Br) in Ethanol The reaction of some sterically demanding trialkylphosphines L = PR2R′ (R = iPr, R′ = tBu; R = tBu, R′ = iPr, Me) with NiX2 (X = Cl, Br) in ethanol affords instead of the expected non-electrolytes [NiL2X2] tertiary phosphonium nickelates [HL][NiLX3] due to participation of the solvent. In case of the less bulky PtBu2Me both complex types were obtained. [Ni(PtBu2Me)2Cl2] is tetrahedral and therefore one of the two examples of paramagnetic bis(trialkylphosphine)dihalogenonickel(II) complexes known so far. In solution the latter compound undergoes an equilibrium of tetrahedral (paramagnetic) and planar (diamagnetic) conformer. Vis spectra as well as the results of magnetic measurements and 1H and 31P NMR investigations are reported.

After a brief review of previous work the results of the metathesis reaction between Ni(dme)Br2 and R2P(O)NR′Li [R = tBu, iPr, Ph; R′ = Et, Pr, iPr, (±)-sBu, tBu, tPen, Cy, Ph, (–)-α-methylbenzyl = Mb, 1-adamantyl = Ad] are reported. Complex formation occurred only with lithiated amides of tert-butylphosphinic acid, and bischelates [tBu2P(O)NR′]2Ni were obtained when R′ = sBu, Mb, tPen, Ad (1d – g). With R′ = Et, Pr bischelation was incomplete. Vis spectroscopy showed the paramagnetic compounds 1d – f to be planar in the solid state but tetrahedral in solution. 1g is tetrahedral in both phases. The planar structure of 1f was confirmed by X-ray single-crystal analysis (monoclinic, space group P21/n). The magnetic moments μeff of 1d, e, g are ca. 3.2–3.5 μB in both phases and the Curie-Weiss law is obeyed in the range 293–183 K. The same is valid for dissolved 1f. The μeff values of solid 1f are however, strongly temperature-dependent, varying from 1.38 to 0.55 μB (300–90 K). NMR data (31P, 1H, 13C) are reported. Obviously, a favorable combination of electronic and steric factors of substituents R and R′ produces with ligands [R2P(O)NR′]– the donor quality necessary for bischelation as well as the singular field strength required for the formation of planar paramagnetic species. As the combination of paramagnetism and planarity is bound to the solid state, lattice energy effects may be finally decisive for this unique constellation of tetracoordinated NiII complexes.

Dimethyl disulfide and dimethyl diselenide are known to readily undergo charge exchange with gaseous conventional radical cations containing oxygen, nitrogen, and sulfur functionalities. In sharp c...

The reactivity of the prototypical phosphorus-containing ylidion (α-distonic ion) •CH2PH3+ has been investigated in the gas phase by using a dual cell Fourier-transform ion cyclotron resonance mass spectrometer. The ion •CH2PH3+ and its more stable conventional isomer CH3PH2•+ show distinctly different reactivities toward neutral reagents. This observation contrasts the facile interconversion of the analogous sulfur- and oxygen-containing distonic ions •CH2SH2+ and •CH2OH2+ with their conventional isomers CH3OH•+ and CH3SH•+, respectively, within collision complexes in the gas phase. Bracketing experiments yield a proton affinity of 190.4 ± 3 kcal mol-1 for the phosphorus atom in •CH2PH2. Together with a calculated heat of formation for •CH2PH2, this value yields a heat of formation of 217 ± 3 kcal mol-1 (at 298 K) for the distonic ion •CH2PH3+.

P,P-Diorganylphosphinic amides R2P(O)NHR' (R = ‘Bu, 1Pr, Ph; R’ = Et, Pr, Cy, 1Pr, 1Bu, Ph, etc.) have been prepared by reaction of R2PCl with the corresponding lithiated mine followed by oxidation with H2O2. Their 31P and 13C NMR spectra are discussed.

Using the technique of neutralization-reionization mass spectrometry (NRMS) it could be shown that the elusive phosphorotrithious acid (HS)3P is a stable molecule in the rarefied gas phase. A triple propene elimination from the molecular ions of the dipropyl ester of propylphosphonotrithioic acid, PrP(S)(SPr)2, (70 eV EI) yields m/z 130 radical cations of composition “[H3PS3] +”. Analysis of their collisional activation (CA) mass spectrum using thermochemical data, shows that these “[H3PS3] +” ions have the structure [(HS)3P] + rather than that of the tautomer [(HS)2P(=S)H| +. Subjected to a NRMS experiment, these ions retain their structure and are cleanly reduced to (HS)3P. The results are entirely compatible with ab initio MO-calculations executed at the HF/3-21G∗ and HF/6-31G∗∗ levels of theory (GAUSSIAN 92 system of programs). The calculations predict that [(HS)3P] + and [(HS)2P(=S)H] + and their respective neutral counterparts are local minima which are separated by high potential energy ba...

Starting from Mo(CO)6 and disulfanes R2P(S)-S-S-P(S)R2 the “trimetallic” tetranuclear clusters Mo2WCuS4I(R2PS2)4 3 (R = Et (a), Pr (b)) were obtained via the dinuclear compounds Mo2S4(R2PS2)2 1 and the trinuclear complexes Mo2WS4(R2PS2)4 2. The crystal structure of 3b shows a cubane-type core Mo2WCuS4. Both Mo atoms and the W atom are chelated by a dithiophosphinato ligand. One Mo and the W atom are bridged by the fourth ligand. The coordination of W and Mo2 is octahedral, of Mo1 trigonal bipyramidal, and of Cu tetrahedral.

Crystal structure analysis of (CO)5CrPH2COOH (a = 1338.2, b = 622.6, c = 1161.5 pm, β = 96,77°, P21/c, Z = 4, R = 0.0330) has shown the complex to be dimerized via hydrogen-bonds of the COOH group. Geometrical parameters of the hypothetical free ligand [H2PCOOH]2 were calculated using the HF/3-21 G*, HF/6-31G** and MP2-FU/6-31 G** basis sets. Bond lengths and bond angles of the calculated free ligand are similar to those derived from the crystal structure analysis of the coordinated ligand and are not significantly influenced by coordination and/or intermolecular interactions.

Metal carbonyl complexes containing phosphinoformic acids, including the parent compound H2PCOOH, have been made by the following route: (CO)5MPRR′H → (CO)5MPRR′Li → (CO)5MPRR′COOLi → (CO)5MPRR′COOSiMe3 → (CO)5MPRR′COOH (R = organyl, H; M  Cr, W). While the uncoordinated silyl esters RR′PCOOSiMe3 spontaneously decompose to RR′PH, CO2 and Me3SiOH in protic media the last step in the sequence above can be safely brought about by silica gel. So far only chromatography on silica gel has been found to provide the mild conditions necessary to avoid decarboxylation of the ligated esters during protolysis. Some reactions of (CO)5MPRR′COOLi are reported and compared with those of the free ligands RR′PCOOLi. The structures of the complexes have been confirmed by spectroscopic methods (IR, MS, 1H-, 13P-, 13C-NMR).

Die Reaktion von Mo3S4(R2PS2)41 (a: R = Et, b: R = Pr) mit HgI2 in THF ergibt die diamagnetischen Komplexe [Mo3S4(R2PS2)4HgI2] 3. Die Kristallstrukturanalyse von [3a (H2O)] · 2 CH2Cl2 zeigt eine triangulare Anordnung der Mo-Atome, die durch μ2S-Atome verbruckt und durch ein μ3S-Atom uberdacht sind. Jedes Mo-Atom ist durch einen Dithiophosphinatoliganden Et2PS2− chelatisiert, ein weiterer Et2PS2−-Ligand verbruckt zwei Mo-Atome, wahrend ein H2O nur schwach an das dritte Mo-Atom gebunden ist. Somit ist jedes Mo-Atom verzerrt oktaedrisch koordiniert. HgI2 ist „peripher” an den Cluster uber je ein S-Atom eines Chelatliganden und des Bruckenliganden gebunden. Raumgruppe P1, Gitterkonstanten a = 12,157(2), b = 15,284(3), c = 16,049(3) A, α = 115,56(1), β = 107,35(1) und γ = 94,62(1)°; Z = 2, dber = 2,23 mg/mm3; 4 236 beobachtete Reflexe, R = 0,068. In organischen Losungsmitteln sind die Komplexe 3 starke Elektrolyte. Gemas VT-31P-NMR-Messungen wird eine schrittweise Dissoziation von 3 vorgeschlagen, wobei sich unter Eliminierung des Bruckenliganden aus dem Cluster [Mo3S4(R2PS2)3] +[(R2PS2)HgI2]− bildet. Peripheral Bonding of Mercury(II) Iodide to Trinuclear Molybdenum-Sulfur-Dithiophosphinato Clusters: [Mo3S4(R2PS2)4HgI2] (R = Et, Pr) Reaction of Mo3S4(R2PS2)41 (a: R = Et, b: R = Pr) with HgI2 in THF yields the diamagnetic title complexes [Mo3S4(R2PS2)4HgI2] 3. The crystal structure of [3a (H2O)] · 2 CH2Cl2 shows the complexes to consist of a triangular array of Mo atoms which are bridged by μ2S atoms and capped by a μ3S atom. Each of the Mo atoms is chelated by a dithiophosphinato ligand Et2PS2− and in addition two Mo atoms are bridged by a Et2PS2− ligand while the H2O molecule is bonded weakly to the third Mo atom. Thus, all Mo atoms reveal a distorted octahedral coordination sphere. HgI2 is „peripherally” bonded to the cluster via two S atoms, one of which belongs to a chelating ligand and the other one to the bridging ligand. Space group P1, lattice constants a = 12.157(2), b = 15.284(3), c = 16.049(3) A, α = 115.56(1), β = 107.35(1), and γ = 94.62(1)°; Z = 2, dcalc = 2.23 mg/mm3; 4 236 observed reflections, R = 0.068. In organic solvents complexes 3 are strong electrolytes. VT-31P NMR data suggest a stepwise dissociation of 3 with formation of [Mo3S4(R2PS2)3] +[(R2PS2)HgI2]− and elimination of the bridging ligand from the cluster.

Reactions of clusters Mo 3 S 4 L 4 ( 2 ) (L=R 2 P(S)S − ; R=Et ( a ), Pr ( b )) with MI 2 (M=Zn, Cd, Hg) in the presence of pyridine yieided ionic clusters [Mo 3 S 4 L 3 py 3 ] + [MI 3 py] − (M=Zn ( 9 ), Cd ( 10 ); R=Et ( a ), Pr ( b )) and [Mo 3 S 4 L 3 py 3 ] + [HgI 3 ] − ( 11 ) (L=Pr 2 P(S)S − ), respectively. The cluster cations consist of a triangular array of Mo atoms which are bridged by three S atoms and capped by the fourth S atom. Each of the Mo atoms is chelated by one L and coordinated by one pyridine. 9a crystallizes in the monoclinic space group P 2 1 with Z =2 formula units in the unit cell of dimensions a =1120.9(2), b =1756.3(3), c =1447.3(2) pm, β=105.31(1)°, D c =1.98 mg/ mm 3 . The crystal structure was refined to R = 0.04 using 5599 observed reflections and consists of [Mo 3 S 4 (Et 2 PS) 3 py 3 ] + [ZnI 3 py] − . The coordination number of the Mo atoms is 8. The average distance MoMo is 276.6(2) pm. The Zn atom is coordinated tetrahedrally with average distance ZnI of 259.0(2) and ZnN of 208.8(11) pm.

The preparation of lithiumphosphinoformates R2PCOOLi 1 (R = Ph, c-Hexyl, i-Pr, Et) and RHPCOOLi 2 (R = Ph, c-Hexyl) from R2PLi or RPHLi and CO2 is described. In the latter reaction RP(COOLi)2 3 and RPH2 are formed in addition to 2. In protic media 1–3 are rapidly decomposed with decarboxylation and formation of R2PH and RPH2, respectively. Reactions of 1 with McI, (MeO)2SO2, Me3SiCl and CS2 are similar to those of Ph2PCOONa and no significant influence of R was detected. With (MeO)2SO2 mixtures of 2 and 3 gave esters RHPCOOMe and RP(COOMe)2 while with Me3SiCl RHPCOOSiMe3 was obtained as the sole product. Ab initio MO calculations (GAUSSIAN 90 system of programs; HF/3-21G∗, HF/6-31G∗∗ and MP2/6-31G∗∗ basis sets) showed the phosphinoformic acid to be less stable than its decomposition products, from which it is separated by a high barrier of isomerization. Therefore the acid should be stable in the rarefied gas phase. Die Darstellung der Lithiumphosphinoformiate R2PCOOLi 1 (R = Ph, c-Hex, i-Pr, Et)...

An ab initio study was made of the radical anions of thioxophosphane (H-PS) and thiohydroxyphosphinidene (H-S-P). Geometries were optimized at the UHF/3-21G ∗ , UHF/6-31G ∗∗ , UHF/6-31++G ∗∗ and UMP2/6-31++G ∗∗ levels of theory. Furthermore, the transition state between [H-P-S] .− and [H-S-P] .− was determined. The calculations show that [H-P-S] .− is more stable than [H-S-P] .− , with a significant barrier to isomerization. The opposite order of stability for the corresponding cations has been found previously.

Removal of HCl from (CO)5MPRHCl (M  Cr, Mo, W; R  Ph, NEt2) by treatment with NEt3 has given the complexes (CO)5,MPh(H)PP(Cl)PhM(CO)5 (M Cr, Mo, W) (1) and (CO)5CrNEt2(H)PP(Cl)NEt2Cr(CO)5 (2) containing bridging diphosphine ligands. Surprisingly, (CO)5CrCl2PPCl2Cr(CO)5 (3) was formed from treatment of (CO)5CrPHCl2 with NEt3. Reaction of 1 with tetrabutylammoniumfluoride, of 2 with gaseous HCl, and of 3 with MeOH gave (CO)5,CrPh(H)PP(F)PhCr(CO)5, (4), (CO)5CrCl(H)PPCl2Cr(CO)5 (5) and (CO)5Cr(MeO)2PP(OMe)2Cr(CO)5 (6) respectively. Except for Cl2PPCl2, the diphosphine ligands in 1–6 are unknown in the free state. Attempts to abstract HCl from 1 to give the diphosphene complex (CO)5CrPhPPPhCr(CO)5 failed.

The syntheses of tetranuclear complexes Mo,W2S4L6 3 and Mo2Co2S4L2(CO)2(CH3CN)2 4 (L = R2PS2⁻; a: R = Et, b: R = Pr) containing the cubane-type Mo2M2S4 core are reported. While in 4 both Mo atoms are chelated by L, the dithiophosphinato group acts as a chelating and bridging ligand in 3. It is shown that there exist four isomers of 3 which differ not only in the function of L but also in the kind of metals which are chelated and bridged. Magnetic and NMR spectroscopic data are given. The structure of a mixed crystal of the two β-isomers of 3a containing three bridging and three chelating ligands L is reported: orthorhombic space group Pbca, Z = 8, and lattice parameters a = 2186.6(7), b = 2264.0(7), and c = 2386.7(6) pm.

The diamagnetic tetranuclear cluster complexes Mo3CuS4I(R2PS2)4•C5H5N 2 (a: R=Et, b: R=Pr) are obtained by reaction of Mo3S4L4 (L = R2PS2-) 1 with CuI and pyridine. Each Mo atom of the cubane-type Mo3CuS4 core is chelated by L. Two of the Mo atoms are bridged by the fourth L, while a pyridine ligand completes the coordination sphere of the third Mo atom, and iodine is bonded to the Cu atom. Magnetic, NMR- and MS-spectroscopic data are given. 2b crystallizes in the monoclinic space group P21/n with Z = 4 and lattice parameters a = 21,164(7), b = 10,653(3), c = 25,455(8)Å, and β = 106,25(3)°.

The dissociative ionization by electron impact (70 eV) of tetraphosphorus trisulfide, P4S3, yields [P3S]+ and [PZS]+0 ions whose structures have been investigated by means of Coliisionai Activation (CA) mass spectra. Using the technique of Neutralization-Reionization mass spectrometry (NRMS) it is shown that both ions can be reduced to the corresponding neutral molecules. Thus, triphosphorus sulfide and diphosphorus sulfide are viable molecules in the rarefied gas phase. The results of ab initio MO calculations were used to interpret the experimental findings. Tetrahedral (C3v) and triangular (C2v) structures are proposed for the [P,S]+ and [PZS]+0 ions respectively.

Durch Umsetzung von MCl2 mit [R2P(S)NR ′]Li wurden die Thiophosphinsaureamidato-Chelate [R2P(S)NR ′]2M (R, R′ = Organyl; M = Ni, Co) 1, 2 erhalten. Magnetischen und spektroskopischen Messungen (UV/VIS) zufolge sind die NiII-Komplexe 1 d (R = i-Pr, R′ = Me), 1 h (R = t-Bu, R′ = Me), 1i (R = t-Bu, R′ = Et) und 1m (R = t-Bu, R′ = Ph) im Festkorper planar, wobei fur 1i trans-Stellung der Donatoratome im Chromophor NiN2S2 nachgewiesen wurde. Im Festzustand weisen die NiII-Komplexe 1a (R = Me, R′ = i-Pr) und 1 b (R = Me, R′ = c-Hex) magnetische Momente von ca. 1,2 B.M. auf, wahrend die aller anderen Komplexe 1, 2 in einem Bereich liegen, wie man ihn bei tetraedrischer Koordination erwartet. In Losung erweisen sich 1 c (R = Me, R′ = t-Bu), 1 e–g (R = i-Pr; R′ = i-Pr, c-Hex, t-Bu) und 1 j–l (R = t-Bu; R′ = i-Pr, c-Hex, t-Bu) als rein tetraedrisch, wahrend 1 a, 1 b, 1 i und 1 m einem Konformerengleichgewicht planar ⇌ tetraedrisch unterliegen, das sich mit steigender Raumerfullung von R und R′ nach rechts verschiebt. Der Einflus von R ist hierbei geringer als der von R′. Kristallstrukturanalysen fur 1 k (R = t-Bu, R′ = c-Hex) und 2 a (R, R′ = t-Bu) bestatigen eine verzerrt tetraedrische Koordination. 1 k: rhombisch, a = 1 343,7(1), b = 1 514,9(1), c = 1 632,4(2) pm; Pccn, Z = 4; 3 205 Reflexe, R = 0,03. 2 a: rhombisch, a = 1 637,9(2), b = 2 997,0(3), c = 1 282,4(1) pm; Pbca, Z = 8; 4 742 Reflexe, R = 0,04. Nickel(II) and Cobalt(II) Phosphinothioic-N-Organylamidato Chelates [R2P(S)NR′]2M: Magnetic Properties and Crystal Structures Phosphinothioic-N-organylamidato chelates [R2P(S)NR′]2M (R, R′ = organyl; M = Ni, Co) 1, 2 have been obtained by reaction of MCl2 with [R2P(S)NR′]Li. According to magnetic and spectroscopic measurements (UV/VIS) NiII complexes 1 d (R = i-Pr, R′ = Me), 1 h (R = t-Bu, R′ = Me), 1 i (R = t-Bu, R′ = Et) and 1 m (R = t-Bu, R′ = Ph) are planar in solid state. For 1 i transgeometry of the donor atoms in the chromophore NiN2S2 has been proved. NiII complexes 1 a (R = Me, R′ = i-Pr) and 1 b (R = Me, R′ = c-Hex) show magnetic moments of c. 1.2 B.M. Magnetic moments of all other solid complexes 1, 2 are in a range usually found with tetrahedral coordination. In solution 1 c (R = Me, R′ = t-Bu), 1 e–g (R = i-Pr; R′ = i-Pr, c-Hex, t-Bu), and 1 j–l (R = t-Bu; R′ = i-Pr, c-Hex, t-Bu) are entirely tetrahedral while with 1 a, 1b, 1 i, and 1 m there exists an equilibrium planar ⇌ tetrahedral. This is shifted to the right with increasing R and R′ the influence of R being less than that of R′. The crystal structures of 1 k (R = t-Bu, R′ = c-Hex) and 2 a (R, R′ = t-Bu) reveal a distorted tetrahedral coordination. 1 k: orthorhombic, a = 1 343.7(1), b = 1 514.9(1), c = 1 632.4(2) pm; Pccn, Z = 4, 3 205 reflections, R = 0.03. 2 a: orthorhombic, a = 1 637.9(2), b = 2 997.0(3), c = 1 282.4(1) pm; Pbca, Z = 8, 4 742 reflections, R = 0.04.

The dissociative ionization by electron impact (70 eV) of tetraphosphorus trisulfide, P4S3, yields [P3S]+ and [PZS]+0 ions whose structures have been investigated by means of Coliisionai Activation (CA) mass spectra. Using the technique of Neutralization-Reionization mass spectrometry (NRMS) it is shown that both ions can be reduced to the corresponding neutral molecules. Thus, triphosphorus sulfide and diphosphorus sulfide are viable molecules in the rarefied gas phase. The results of ab initio MO calculations were used to interpret the experimental findings. Tetrahedral (C3v) and triangular (C2v) structures are proposed for the [P,S]+ and [PZS]+0 ions respectively.

Diamagnetic clusters [Mo3X-μ-(S2)3-μ3(S)(R2PS2)3] 2-4 (2: X = Cl; 3: X = Br; 4: X = I; 2-4: a: R = Et; b: R = Pr; c: R = Bu) are conveniently obtained by reaction of [Mo3S7(R2PS2)3]+(R2PS2)- 1 either with alkyl halides RX or with tetraalkylammonium halides R4NX. Between halogen X and one of the S atoms of each disulfido bridge there exist bonds which seem to be mainly of covalent character. Thus X is incorporated into the cluster core leading to a cubane type structure. [Mo3ClS7(Et2PS2)3] forms orthorhombic crystals with space group Pnma, Z = 4, a = 1931.9(7), b = 1551.2(6), c = 1286.5(4) pm. Isostructural substructures of 3b, 4a and 4b (space group P21) were also studied. All these cluster molecules reveal similar core geometries with distances S—Cl 239.4(4), S—Br 305(1) and S—I 322.5(3) pm much less than the sum of the van der Waals radii. The results of structural and spectroscopic investigations are discussed.

Ph 2 PCOONa 2, hergestellt dutch Reaktion von Ph2PNa mit CO2, wird in protischen Medien rasch unter Bildung von Ph2PH and CO2 hydrolysiert. Die Hydrolyse verlauft in Natronlauge sehr viel langsamer and es bilden sich zusatzlich geringe Mengen Ph2P(O)O− und HCOO−, Aus 2 and stochiometrischen Mengen RI bilden sich tertiare Phosphine Ph2PR (R[dbnd]Me, Et) wahrend mit uberschussigem MeI das Phosphoniumsalz [Ph2PMe2]I erhalten wird. Ph2PCOOMe, Ph2PCOOSiMe3 bzw. Ph2PCSSNa wurden durch Umsetzung von 2 mit (MeO)2SO2, Me3SiCl bzw. CS2 synthetisiert. Ph2P(O)ONa and Ph2P(S)SNa entstanden bei der Reaktion von 2 mit O2 oder S8 in Benzol. Concerning Sodiumdiphenylphosphinoformiate Ph2PCOONa1. Ph2PCOONa 2, prepared from Ph2PNa and CO2, is readily hydrolyzed in protic media with formation of Ph 2 PH and CO2. Hydrolysis is much slower in NaOH and small quantities of Ph2P(O)O− and HCOO− are additionally formed. Reactions of 2 with RI in stoichiometrical amounts gave tertiary phosphines Ph2PR (R[dbnd]Me, Et) while ...

Starting from compounds (CO)5MPRClNEt2 (M = Cr, Mo, W) several new complexes have been obtained in which phosphines—non-existent or having a different tautomeric structure in the free state—are stabilized by coordination to a metal(0) centre. Thus, hydrolysis yields (CO)5CrPR(OH)2, methanolysis (CO)5CrPR(OMe)NEt2 and reduction with LiAlH4 (CO)5MPRHNEt2. The latter were converted into (CO)5MPRHCl with gaseous HCl.

Chiral phosphines L and L′ of general formula [(R2′N)ArP(S)-S-]nPR(NR2′)2-n(Ar=Aryl; L: n=1; L′: n=2)1–5 can behave as mono- or bidental ligands in metal(O)carbonyl complexes. With L compounds (CO)5ML(Ar: 4-Methoxyphenyl=An; R=Cyclohexyl, (-)Menthyl; R′=Me, Et; M=Cr, W) or chelate complexes (CO)4CrL (Ar: An; R=Ph, (-)Menthyl, t-Bu; R′=Me, Et) have been obtained. L being coordinated via γ′-P or γ′-P and S of the P(S)-group. In contrast to L the ligands L′ (Ar=An, 2-Naphthy1, 2-Thienyl; R=Ph, Cyclohexyl; R′=Me, Et) gives only chelates (CO)4CrL′ in which one of the two P(S)-groups of the ligand remains uncoordinated. Structures and stereoisomerism of these complexes are deduced from their IR- as well as their 31IP{1H}- and 13C-NMR-spectra. Die chiralen Phosphine L und L′ [(R2′N)ArP(S)-S-]nPR(NR2′)2-n (Ar=Aryl; L: n=1; L′: n=2)1–5 fungieren je nach den Reaktionsbedingungen in Metall(O)carbonylkomplexen als mono- oder bidentale Liganden. So erhalt man mit L die Verbindungen (CO)5ML(Ar: 4-Methoxyphenyl...

P.P-Dialkylthiophosphinsaureamide R2P(S)NHR' (R=Me, 'Pr, 'Bu; R'=Me, Et, iPr. cHex. tBu. Ph. etc.) wurden erhalten durch Umsetzung von R2PNHR' mit Schwefel oder durch Reaktion von Me2P(S)CI mit primaren Aminen. Ihre 31P- und 13C-NMR-Spektren werden diskutiert. Insbesondere die Di-t-butylthiophosphinsaureamide sind auszilg;ergewohnlich stabil gegen Hydrolyse und Luftsauerstoff. P,P-Dialkylthiophosphinic acid amides R2P(S)NHR' (R=Me. iPr. tBu; R'=Me, Et, iPr, cHex. tBu, Ph. etc.) have been obtained by reaction of the corresponding aminophosphines with sulfur or by reaction of dimethylthiophosphorylhalides with primary amines. Their 31P- and 13C-NMR spectra are discussed. The di-t-butylthiophosphinic compounds proved to be remarkably stable against moisture and oxygen.

Aminophosphine des Typs Rn P(NR′2)3-n (n= 2, 1, 0; R = Ph, c-Hex, (-)Men, t-Bu; R′= Me, Et, n-Bu) reagieren mit 2, 4-Bis(aryl)-1, 3, 2, 4-dithiadiphosphetan-2, 4-disulfiden (ArPS2)2(Ar: Ph, 4-Methoxyphenyl = An, Naphthyl, Thienyl) unter formaler Insertion monomerer {ArPS2)-Einheiten in eine oder in zwei der λ3-P—N-Bindung zu chiralen Organophosphorverbindungen Ar(R′2N)P(S)—S—PRn (NR′2)2-n(n = 2, 1, 0) und [Ar(R′2N)P(S)—]2PR2(NR′2)1-n (n = 1.0). In diesen werden bei Raumtemperatur bevorzugt die λ3—P—N—und λ3—P—S-Bindungen durch H2O oder Methanol unter Bildung von Produktgemischen solvolysiert. Mit Chlorwasserstoff bildet sich aus An(Et2N)P(S)—S—PPh(NEt2) das An(Et2 N)P(S)—S—PPh(C1). Addition von Schwefel fuhrt zu Ar(R′2N)P(S)—S—P(S)Rn (NR′)2-n (n=2, 1). Die Stereoisomerenbildung der neuen Verbindungen wird besprochen und ihre Struktur sowie die Zusammensetzung der Reaktionsmischungen aus den 31P-Spektren hergeleitet. Aminophosphines Rn P(NR′2)3-n (n = 2, 1, 0; R = Ph. c-Hex, (-)Men, t-Bu; R′= Me, ...

The cubane-type diamagnetic cluster Mo3SnS4(Et2PS2)6 (1) is obtained by reaction of the “incomplete” cubane Mo3S4(Et2PS2)4 either with tin powder and Et2P(S)—S—S—P(S)Et2 or with bis(diethyldithiophosphinato)tin(II). While the Sn atom and two of the Mo atoms in the core are chelated by Et2PS2⁻, the remaining Mo atom serves as a bridgehead for three dithiophosphinato-ligand bridges to the other metals. 1 crystallizes in the orthorhombic space group Pbca with Z = 8 and lattice parameters a = 2240( 1), b = 2261 ( 1), c = 2401 (1) pm.

Durch doppelte Alkeneliminierung entstehen aus den Molekulionen (El: 70 eV) von Dialkyldithiophosphinsauren R2P(S)SH (R: Et, nPr, nBu) Radikalkationen der Zusammensetzung [H3PS2]+. (m/z 98). Aus der Analyse des Stosaktivierungs(CA)-Massenspektrums und aus thermochemischen Daten ergibt sich, das [H3PS2]+. als ein Gemisch der Formen [HP(SH)2]+. und [HSPSH2]+. mit tri- bzw. dikoordiniertem Phosphor vorliegt. Eine Struktur mit tetrakoordiniertem Phosphor und P(S)-Gruppe, die einer ionisierten Dithiophosphinsaure H2P(S)SH entsprechen wurde, ist hingegen nicht zu beobachten. Mittels Neutralisations-Reionisations-Massenspektrometrie (NRMS) konnten neutrale Molekule „H3PS2” erzeugt werden, die sich als stabil in der verdunnten Gasphase erweisen und bevorzugt als HP(SH)2 vorliegen sollten. Die experimentellen Befunde stehen im Einklang mit den Ergebnissen semiempirischer MO-Rechnungen (MNDO). Gaseous “H3PS2” – Generation and Characterization Double alkene elimination from molecular ions (El: 70 eV) of dialkyldithiophosphinic acids R2P(S)SH (R: Et, nPr, nBu) leads to radical cations of composition [H3PS2]+. (m/z 98). By analysis of the collisional activation (CA) mass spectrum and using thermochemical data it was shown that [H3PS2]+. exists as a mixture of structures [HP(SH)2]+. and [HSPSH2]+. containing tri- or dicoordinated phosphorus, respectively. No structure corresponding to ionized dithiophosphinic acid H2P(S)SH was observed. Via neutralization reionization mass spectrometry (NRMS) neutral molecules „H3PS2” were obtained which proved to be stable in the dilute gas phase and most probably are of structure HP(SH)2. Experimental findings are in accordance with the results of semiempirical MO-calculations (MNDO).

Using the technique of neutralization-reionization mass spectrometry(NRMS) we have shown that the elusive thioxophosphane H-P=S and its tautomer H-S-P, (thiohydroxy)phosphinidene, are stable molecules in the gas phase. H-S-P .+ radical cations, generated by electron impact ionization of diethylphosphine sulfide, (C 2 H 5 ) 2 HP=S, are cleanly reduced to H-S-P; whereas H-P=S .- anions, generated in a negative chemical ionization (NCI) experiment with the diethylphosphine sulfide, are readily oxidized to H-P=S

The crystal structure of the title compound, [(t)Bu(2)P(S)N(i)Pr](2)Ni or [Ni(C(11)H(25)NPS)(2)], shows a dihedral angle of 82.27 (6) degrees between the two Ni/S/N planes and thus a distorted tetrahedral arrangement of the NiN(2)S(2) chromophore. The structure is in accordance with the observed paramagnetism and is contrasted with the oxo analogue, which is planar but also paramagnetic.

New Results Concerning the “Phosphorus Monosulfide” (PS)x The orange-yellow solid of approximate composition (PS)x obtained by dehalogenation of P(S)Br3 with Mg proved to be a mixture of phosphorus sulfides e.g. P4S3, P4S4, P4S5, P4S7, and insoluble polymeric material. It is suggested that the latter contains a network of triply connected P atoms, many of which are substituted by groups. The conclusions are based on the results of analytical, mass-spectrometric and 31P-NMR-spectroscopic findings.

Das vollstandige Manuskript dieser Zuschrift erscheint in: Angew. Chem. Suppl. 1982, 1962. DOI: 10.1002/ange.198219620

The title paramagnetic compound, chloro-2κCl-[di-tert-butyl­phos­phinic ethylamide-1κO]­bis­[μ-di-tert-butyl­phos­phin­ic ethyl­amidato(1−)-1:2κ4O:N]­lithium(I)­nickel(II), [NiLiCl(C10H23NOP)2(C10H24NOP)], revealed an incomplete bischelation of Ni2+ by L− {L = [tBu2P(O)NEt]−}, with the formation of a pseudo-tetrahedral NiON2Cl chromophore. The Ni atom is coordinated by Cl−, bidentate L− and mono­dentate LLi (via N).