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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+.

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.

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)°.

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.

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.

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

By reaction of M(CO)6 (M = Cr, Mo, W) with the bifunctional aminophosphane Ph(NEt2)P-(CH2)4-P(NEt2)Ph (L-L) octahedral complexes (CO)4M cis(L-L) are obtained. While it is shown by 31P{1H} NMR spectroscopy, that these complexes contain meso-and rac-(L-L) to a different extent, there is evidence from 13C{1H} NMR data obtained for the Mo complex, that the rac-ligand always prevails. As racemisation is observed when the Mo complex reacts with HBr to give (CO)4Mo-cis[Ph(Br)P-(CH2)4-P(Br)Ph] an SN 1-mechanism is suggested for this reaction.

Vinylaryldithiophosphinic acids RR′P(S)SH (R = vinyl; R′ = p-methoxyphenyl, p-ethoxyphenyl) were obtained as NH4-salts from the reaction of aryldithiophosphonic anhydride with CH2=CHMgBr. Alkali hydrolysis of the methylester RR′P(S)SCH3 (R′ = p-methoxyphenyl) gave β-methylnercaptoethyl-p-methoxyphenylthiophosphinic acid.

By reacting RC ≡ CMgBr (R = CH3, C2H5, (CH3)Si) with perthiophosphonic anhydrides (R′PS2)2 (R′ = CH3, 4-CH3O-C6H4) alkynyl substituted dithiophosphinic acids RC ≡ C(R′)P(S)SX (X = H) are obtained, the ammonium salts of which can be converted into the esters (X = CH3) with CH3I. While the acids and their salts form numerous metal chelates (X = M/n), the corresponding esters give platinum(0) alkyne complexes [(PPh3)2Pt(RCEEC(R′)P(S)SCH3)] on reaction with Pt(PPh3)4.

Compounds RPBr2Cr(CO)5 (R = Me, Et, i-Pr. t-Bu, c-Hex. (-)Menthyl. Ph) and RPBr2W(CO)5 (R = (-)Menthyl, Ph) are obtained from M(CO)5THF and organodibromophosphane. Dehalogenation of the chromium complexes with magnesium in THF leads to (RP)3[Cr(CO)5]m (m = 1. 2, 3) with m depending on the bulkiness of R. When dissolved in THF the binuclear complexes (m = 2) are gradually converted into mononuclear compounds. The isomeric structure of the cyclotriphosphane complexes is deduced from their 31P{1H} NMR spectra.

Reduction of MentPBr2M(CO)5 1 (M = Cr, W) with magnesium in THF yields the diphos­phene complex (CO)5M(Ment)P=P(Ment)M(CO)5 2 as the main product. In addition, a phosphinidene complex, (CO)5M(Ment)PM(CO)5 (3) is also formed. The latter is obtained in larger amounts, if the reaction is carried out in the presence of M(CO)5THF. The proposed structures are confirmed by NMR and UV data as well as - in the case of the chromium compounds (2a, 3a) - by crystal structure analysis. Compound 2a is obtained only as the frans-isomer. The P-P distance in 2a (204.0 pm) indicates a double bond which does not participate in the complex formation. The P-Cr distance in 3a (average: 230.3 pm) is within the low est range found for this element combination. Reaction of 2a with LiAlH4 yields the diphosphane complex (CO)5CrMent(H)P-P(H)MentCr(CO)5 4 as a mixture of “meso” and “rac” diastereomers.

Various methods for the synthesis of [R,P(X)]2Y are described. High-resolution NMR spectra were analyzed on the basis of [AXn]2 spinsystems and simulated by computer programs.

A mixture of three isomeric clusters of composition Mo3WS4(Et2PS2)6 (3) is obtained by reacting equimolar quantities of Mo3S4(Et2PS2)4, W(CO)3(CH3CN)3 and [Et2P(S)]2S2 in toluene'. Some NMR-spectroscopic data and the magnetic properties of these isomers are reported. Isomer 3a consists of a distorted cubane Mo3WS4, each metal of which is coordinated by six S atoms: three of them belonging to the cubane, one to a bridging and two to a chelating ligand Et2PS2 -. The crystal structure of isomer 3b is reported. In 3b only three of the metals in the core are coordinated in this manner while the fourth is surrounded by three S of the cubane and three S of bridging ligands. 3b crystallizes in the orthorhombic space group Pbca, Z = 8. lattice parameters a = 2184,4(8), b = 2264,4(9). c = 2388.2(8) pm. The crystal structure was refined to R = 0.05 using 5398 observed reflections. By HPLC 3b can be separated into two isomers. 3b1 and 3b2, both differing in the type of metal. Mo or W. bonded to the three bridging ligands

Reaction of (CO)5M • THF (M = Cr, W) with PBr3 gave (CO)5MPBr3 (4) besides (CO)5M-Br2PPBr2-M(CO)5 (5) and (CO)5M[Br2P-O-(CH2)4-Br] (7). Compounds 5, in which P2Br4 is stabilized by coordination, could also be obtained by partial dehalogenation of 4 with magnesium. Complete coupling parameters of 5 (M = W) are deduced from the 183W satellite lines of the 31P NMR spectrum

Preparation and properties of several metal vinylaryldithiophosphinates (CH2=CH)RPS2M/n (R: p-methoxyphenyl; p-ethoxyphenyl) are reported. Copolymerisation of the ammonium salt (CH2=CH)RP(S)SNH4 (R = p- ethoxyphenyl) with methacrylic methylester gave polymers (M∼10,000) which acted as polyfunctional ligands thus giving soluble polymeric metal complexes (M ∼17,000) with Ni(II) and Co(II).

Tetranuclear clusters Mo4S4(R2PS2)6 (4) (a: R = Et, b: R = Pr) with cubane-like cores are conveniently obtained by reacting equimolar quantities of Mo3S4(Et2PS2)4, Mo(CO)6 and R2P(S)-S-S-P(S)R2. 31P NMR and MS data of 4 are reported and the magnetic properties are discussed. 4a crystallizes triclinically with a = 1159.41(6), b = 1162.77(7), c = 2228.54(14) pm, α = 102.660(3), β = 98.382(4), γ = 98.546(5)°. P1̅, Z = 2. The molecule consists of a distorted Mo4S4 cubane. Each Mo atom is coordinated by six S atoms: three within the cubane, two from a bidentate and one from a chelating dithiophosphinato ligand. Two Mo -Mo distances are short- ened by the chelate to an av. of 278.6 pm, while the av. of the remaining four Mo -Mo distances is 287.9 pm.

The 100 MHz 1H NMR spectrum of vinyl-p-anisyl-dithiophosphinic acid trimethylsilylester is analyzed by iterative methods. Data for ABCX and [AB]2X spinsystems are reported.

Reaction of Dialkylthiophosphorylhalides R2P(S)Hal (R = CH3, C,H5, n = C3H7; Hal = Cl, Br) with Hexamethyldisilazane gives in good yields N-Trimethylsilylamides of Dialkylthiophosphinic acids R2P(S)NHSi(CH3)3. The properties and some reactions of these compounds are reported.

Unsymmetrically substituted dithiophosphinic acids RR'P(S)SH give planar metal chelates [RR'PS2]2M 1 [M = Pd(II), Pt(II)]. It can be shown by comparison of their 31P-{1H} NMR spectra with those of symmetrically substituted compounds [R2PS2]2M that in the synthesis of 1 equimolar mixtures of the cis and trans isomers are formed.

Various methods for the preparation of Trimethylsilylesters of Phosphinic acids R2P(X)YSi (CH3)3 (X, Y = O, S) are described. The properties and some reactions of these compounds are reported.

High resolution protonmagnetic resonance spectra are analyzed and refined parameters for coupling constants and chemical schift values in the [AB]2X subspectrum of CH3(p-CH3OC6H4)PS2Na · 2H2O are obtained.

The complete manuscript of this communication appears in: Angew. Chem. Suppl. 1982, 1962. DOI:10.1002/anie.198219620

Dibenzo(d,f )-1,3,2-dioxaphosphorepines, 2,2′ -Biphenylylenephosphoric Acids, Bis (2,2′ -biphenylylenedithiophosphato) - nickel (II), Gas Chromatography

(-)D-and (+)D-4-methoxyphenylmethyl-thiophosphinic acid, quinine salts of (-)D-and (+)D-4-methoxyphenylmethylthiophosphinic acid, checking of resolution by 31P{ 1H} NMR-spectroscopy (-)D-and(+)D-4-CH3OC6H4(CH3)P(S)OH acid were obtained from fractional crystallization of the quinine salt of the racemic acid. 31P{1H} NMR spectroscopy proved to be very useful in checking the separation process as well as the optical purity of the diastereomers and enan­tiomers.