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Item Platinum and palladium complexes of [R2PCH2P(Y)R′2] and [R2PCHP(Y)R′2]− ligands, Y = O,S, or Se: 13C, 31P, 77Se, and 195Pt nuclear magnetic resonance studies and the crystal and molecular structures of trans-[PtCl(PEt3){But2PCH2P(O)Me2}][ClO4] and trans-PtCl(PEt3){Ph2PCH2P(S)But2}|[ClO4](1988) Berry, David E.; Browning, Jane; Dixon, Keith R.; Hilts, RobertReactions of the bisphosphine monochalcogenides, [Ph2PCH2P(Y)R2], Y = O, S, or Se, R = Ph, Pri, or But, with the chloro-bridged dimers [M2Cl4(PR′3)2], M = Pd or Pt, R′ = Et or Bun, in the presence of either NaClO4or NaBF4yield perchlorate and fluoroborate salts of the complex cations cis- and trans-[PtCl(PR′3){Ph2PCH2P(Y)R2}]+. In many cases both cisand transisomers (defined by the relative orientation of the two M—P bonds) are obtained and the precise isomer distribution is a sensitive function of the substituents. Corresponding neutral complexes, cis- and trans-[PtCl(PR′3){Ph2PCHP(Y)R2}], can be synthesized either by deprotonation of the cations using NaH or by use of the salts Li[Ph2PCHP(Y)R2] in the initial bridge cleavage reactions. These and related complexes are characterized by complete 13C, 31P, 77Se, and 195Pt NMR studies and by two crystal structure determinations. The complexes I, trans-[PtCl(PEt3){But2PCH2P(O)Me2}][ClO4], and II, trans-[PtCl(PEt3){Ph2PCH2P(S)But2}][ClO4], crystallize in the monoclinic space group P21/c, respective cell dimensions: a = 15.579(2), b = 13.590(3), c = 13.578(1) Å;β= 105.96(1)°; and a = 14.002(4), b = 16.366(5), c = 15.524(5) Å; β = 106.01 (3)°. Complete X-ray diffraction studies show that both complexes contain closely square planar platinum centres with the R2PCH2P(Y)R′2ligands coordinated via phosphorus and the Y atom so as to form five-membered chelate rings. The molecular dimensions suggest that the bond to sulphur is stronger than that to oxygen and exerts a larger transinfluence.Item Reactivity of coordinated [Ph2PCHP(S)Ph2]- and [Ph2P(S)CHP(S)Ph2]-: two-center, regiospecific reactivity in rhodium and iridium complexes and formation of a disubstituted methylene bridge between platinum atoms(1988) Browning, Jane; Dixon, Keith R.; Hilts, RobertReaction of methyl iodide with [Ir(Ph,P(S)-CHP(S)Ph,](cod)] occurs in a regiospecific sequence to form first [Ir{Ph,P(S)CHMeP(S)Ph,](cod)] I and only subsequently [IrMeI(Ph,P(S)CHMeP(S)Ph,](cod)] I. For [Rh-(Ph,PCHP(S)Ph,](cod)] the addition sequence is reversed. [Pt(Ph,P(S)CHP(S)Ph,)(MeOcod)] shows both ligand and metal site reactivity in transforming a novel dimer, [Pt,{Ph,P(S)CP(S)Ph,)(MeOcod),] , containing a quaternary carbon bridge between two platinum centers. The bridging carbon is part of four-member C,S chelate rings at both platinums.Item Polymeric ruthenium( I) and binuclear ruthenium(1) and osmium(1) carboxylate-bridged complexes containing diphosphine, diarsine, arsinophosphine, diphosphine chalcogenide, and dithioether ligands: the structure of [Ru2( CO) 4( p-02CMe) 2( MeSCH2SMe)l2.THF(1990) Steyn, Margo M. de V.; Hilts, Robert; Sherlock, Stephen J.; Cowie, Martin; Singleton, EricThe addition of 1 molar equiv of the bidentate ligands L~L, R'2P(CH2)„PR'2, R'2As(CH2)„AsR'2, Ph2P(CH2)2AsPh2, Ph2PCH2P(S)Ph2, Ph2P(S)CH2P(S)Ph2, and R'SCH2SR' (R' = Me, Ph; = 1-4), to THF/acetone solutions of either the polymer [Ru2(CO)4(g-02CMe)2]ilor the dimers [Ru2(CO)40i-O2CR)2(NCMe)2] (R = Me, Et) affords a new class of polymeric species, [Ru2(CO)4(m-02CR')2(L L)]„, in which the carboxylate-bridged dimeric units are linked by the bidentate L~L ligands. The use of 2 molar equiv of either Ph2PCH2PPh2 (dppm) or Ph2PCH2P(S)Ph2 (dppmS) in the reaction with the acetate-bridged dimer yields complexes of the type [Ru2(C0)4(^-02CMe)2(7j1-Ph2PCH2P(X)Ph2)2] (X = S, electron pair). The osmium analogues [0s2(C0)4(u-02CMe)2(V-Ph2PCH2P(X)Ph2)2] can be obtained by heating [0$2(00)6(µ-020 ß)2] with 2 equiv of dppm or dppmS in CHCI3. The pendant PPh2 moieties of [0s2(C0)4(M-02CMe)2(7j1-dppm)2] can be oxidized to P(0)Ph2 groups by treatment with 2 molar equiv of H202. The structure of the dithioether species [Ru2(CO)40i-O2CMe)2(MeSCH2SMe)]2-THF has been determined by an X-ray diffraction study and has been shown to consist of a polymeric chain of [Ru2(C0)4(g-02CMe)2] units linked by MeSCH2SMe ligands. Each dimer unit has a sawhorse-like arrangement in which the four carbonyls are opposite the bridging acetate groups. The independent Ru-Ru bonds are 2.682 (1) and 2.684 (1) Á. This compound crystallizes in the space group P\ with a = 15.838 (2) A, b = 17.562 (2) A, c = 8.238 (2) A, a = 102.55 (l)°,/3 = 101.87 (1)°, = 68.17 (1)°, V = 2056.3 A3, and Z = 2. The asymmetric unit contains two [Ru2(C0)4(M-02CMe)2(MeSCH2SMe)] moieties. On the basis of 3533 unique observations and 435 parameters varied, the structure was refined to R = 0.046 and Rw = 0.055.Item Dithiophosphinate-bridged ruthenium(I) and ruthenium(II) complexes. The structure of [(Ru2(CO)4(.mu.-S2PMe2)2(PPh3)2].cntdot.1/2CH2Cl2(1990) Hilts, Robert; Cowie, MartinReplacement of the bridging acetate groups in [Ru2(C0)4(M-02CMe)2(PR'2R")2] (R', R" = Ph, Me) by the dithiophosphinate anions R2PS2‘ (R = Me, Ph) yields a new class of dithiophosphinate-bridged Ru(I) complexes, [Ru2(CO)4(m-S2PR2)2(PR'2R")2]· Although the Ru-Ru bond in these species can be reversibly protonated, it does not react with [Au(PPh3)][BF4], diazomethane, or dimethyl acetylenedicarboxylate. Reaction of the related acetate-bridged species [Ru2(C0)4(M-02CMe)2(NCMe)2] with NaS2PMe2 does not yield the expected dithiophosphinate-bridged product but instead gives the mononuclear species [Ru- (CO)2();2-S2PMe2)2] along with Na2S, Na02CMe, MeCN, and Me2P(S)P(S)Me2. An X-ray structure determination of [Ru2- (CO)4(M-S2PMe2)2(PPh3)2]>1/2CH2Cl2 confirms the dithiophosphinate-bridged formulation and shows a long Ru-Ru separation of 2.9000 (6) A and a twisting about the metal-metal axis by ca. 39°. This compound crystallizes in the monoclinic space group P2,/c with cell parameters a = 15.182 (3) A, b = 18.230 (4) A, c = 18.082 (4) A, ß = 94.23 (2)°, and Z = 4. Refinement has converged at R = 0.054 and /?w = 0.082 on the basis of 5928 unique reflections and 365 parameters varied.Item Synthesis and structural characterisation of tris(diphenylthiophosphinoyl)methane and tris(diphenylthiophosphinoyl)methanide complexes of rhodium and iridium; X-ray structures of [Rh(C8H12){η2-C(P(S)Ph2)3-S,S}] and [Ir(CO)2{gh2-C(P(S)Ph2)3-S,S}](1990) Browning, Jane; Dixon, Keith R.; Hilts, Robert; Meanwell, Neil J.Reactions of [MCl(cod)]2, M = Rh or Ir, cod = cyclooctadiene, with CH{P(S)Ph2}3 give the complex cations, [M(cod){CH(P(S)Ph2)3}]+, which are isolated in high yield as BF4− or ClO4− salts. These are the first reported examples of CH{P(S)Ph2}3 complexes in which the methine proton is retained after coordination. The high acidity of this proton is demonstrated by easy deprotonation to corresponding [M(cod){C(P(S)Ph2)3}] complexes. The 31P NMR spectrum of [Rh(cod){CH(P(S)Ph2)3}]BF4 remains a single line to −100°C whereas that of [Rh(cod){C(P(S)Ph2)3}] is resolved into two resonances at −60°C, suggesting that the former complex is 5-coordinate with an η3 (S,S,S) ligand and the latter 4-coordinate, η2 (S,S). The 4-coordinate structure is confirmed by X-ray diffraction studies of [Rh(cod){C(P(S)Ph2)3}] and [Ir(CO)2{C(P(S)Ph2)3}] which both show approximately square planar metal centers, η2 ligands with the third sulfur non-coordinated (“dangling”), and trigonal planar geometry at the central carbon of the tris(phosphinesulfide) ligand. [Rh(cod){C(P(S)Ph2)3}] and [Ir(CO)2{C(P(S)Ph2)3}] crystallize in the Pbca space group (Z = 8) with respective unit cells: a = 20.427(4) Å, b = 16.931(2) Å, c = 23.138(3) Å; and a = 22.140(6) Å, b = 22.317(5) Å, c = 14.792(3) Å. Line shape analysis for a variable temperature 31P NMR study of [Rh(cod){C(P(S)Ph2)3}] gives ΔGo‡ 46 ± 2 kJ mol−1 for the dynamic exchange of coordinated and non-coordinated sulfur.Item Low-valent, heterobinuclear complexes of rhodium and osmium. Influence of the coordinatively unsaturated rhodium center on the reactivity(1991) Hilts, Robert; Franchuk, Roberta; Cowie, MartinItem Reactions of triethylammonium salts of the [(.mu.-CO)(.mu.-RS)Fe2(CO)6]- anion with alkyl-, aryl-, and vinylmercuric halides. Formal C-alkylation of the bridging CO ligand(1991) Seyferth, Dietmar; Archer, Colin M.; Ruschke, David P.; Cowie, Martin; Hilts, RobertThe reaction of alkyl- and arylmercuric halides with [Et3NH][(µ-CO)(p-RS)Fe2(CO)6] gives bridging acyl complexes, (p-R'C=0)(µ-RS)Fe2(CO)6. In the case of vinylmercuric halides the bridging acyl complexes are less stable and, in some cases (CH2=CHHgBr, PhCH=CHHgCl, ClCH=CHHgCl), they undergo decarbonylation to give the µ- , -vinyl complexes, (p-CH=CH2)(p-RS)Fe2(CO)6 in the case of CH2=CHHgBr. Methyl substituents on the vinyl carbon atoms stabilize the µ-acyl complex. The reaction of CH3OCH2CH2HgCl with [Et^NH] [µ-CO) (p-RS)Fe2(CO)g] gave the bridging carboxylato complex (µCH3C02)(p-RS)Fe2(C0)e. Such compounds are more readily prepared by the reaction of Hg(02CR')3 with [ 3 ][(µ-00)(µ- 8) ß2(00)6]. The reaction of Hg(SCH3)2 witii [Et3NH][Oi-CO)(p-PhS)Fe2(CO)6] resulted in formation of (p-CH3S)(p-PhS)Fe2(CO)6. Possible mechanisms of these reactions are discussed. The structure of (p-CH3C02)(p-t-Bu8)Fe2(C0)6 has been determined by X-ray techniques. This compound crystallizes in the triclinic space group Pi with a = 13.608 (2) Á, b = 16.945 (1) Á, c = 8.599 (1) A, a = 98.52 (1)°, ß = 99.00 (1)°, y = 113.03 (1)°, V = 1753.8 Á3, and Z = 4. Refinement has converged at R = 0.055 and Rw = 0.093 on the basis of 325 parameters varied and 3310 unique observations. Both independent molecules have essentially identical geometries in which the Fe2(CO)6 moiety is bridged by a 1,1-dimethylethanethiolate and an acetate ligand.Item Diphosphine-bridged, heterobimetallic complexes containing iridium and osmium. Reversible orthometalation of a bridging bis(diphenylphosphino)methane group at the iridium center promoted by the adjacent osmium center(1991) Hilts, Robert; Franchuk, Roberta; Cowie, MartinThe compound (PPN)[HOs(CO)4] reacts readily with [IrCl(i)1 2-dppm)2] (PPN+ = (Ph3P)2N+, dppm = Ph2PCH2PPh2) at ambient temperature, yielding the heterobinuclear complex [IrOs(H)2(CO)3(#t2-’?3-(oCeH^PhPCI^PPh^(dppm)] (1), in which one phenyl group is ortho-metalated at the Ir center. Treatment of 1 with the electrophile sources HBF4-Et¡>0 or [AuPPh3]BF4 reverses the ortho metalation to give the hydrido-bridged species, [IrOs(CO)3Gt-H)(M-X)(dppm)2][BF4] (X = H (2), AuPPh3 (3)). Deprotonation of 2 with use of NaH regenerates compound 1. The AuPPh3 group in 3 is readily replaced by an iodo group in the reaction with I2 to give [IrOs(CO)3^-H)(/¿-I)(dppm)2] [BF4] (4). Under a CO atmosphere, compound 2 yields [IrOs(CO)6(dppm)2] [BF4] (5), and reaction of 5 with Me3N0-2H20 results in loss of one carbonyl group from the Ir center to yield [IrOs(CO)4(dppm)2] [BF4] (6). The structure of 5 has been determined by X-ray techniques. This compound crystallizes, together with 1.5 equiv of CH2C12, in the monoclinic space group P2,/c, with cell parameters o = 12.063 (2) Á, b = 22.725 (3) Á, c = 22.050 (3) Á, ß = 101.66 (1)°, V = 5920 A3, and Z = 4. The structure has refined to R = 0.043 and f?w = 0.063 on the basis of 5515 unique observations with 444 parameters varied. Compound 5 has a trans-bridging arrangement of diphosphine ligands and has two carbonyls bound to Ir and three on Os. The carbonyl and phosphine arrangement on Os suggests a trigonal bipyramidal (TBP) arrangement characteristic of Os(0), which then forms a dative Os Ir bond to the Ir(+I) center, giving it a TBP geometry also. The Os-Ir separation of 2.9652 (4) A is at the long end of the range expected for a normal single bond.Item Coordination chemistry of [CH{P(S)Ph2}2]−: x-ray diffraction studies of S,S-chelate complexes of iridium and rhodium(1992) Browning, Jane; Bushnell, Gordon W.; Dixon, Keith R.; Hilts, RobertReactions of the chloro-bridged complexes, [M2Cl2(cod)2], M Ir or Rh, with CHR(P(S)Ph2)2, R H or Me, provide a synthetic route to the cations, [M(cod){CHR(P(S)Ph2)2-S,S}]+, which are isolated as fluoroborate or perchlorate salts. Treatment of these products with sodium hydride results in facile deprotonation to the neutral complexes, [M(cod){CR(P(S)Ph2)2-S,S}], and when R H, the neutral complexes are also accessible via reactions of [M2Cl2(cod)2] with Li[CH{P(S)Ph2)2]. The complexes, [Ir(cod){CH(P(S)Ph2)2-S,S}], and [Rh(cod){CH(P(S)Ph2)2-S,S}], crystallize in the P1 (No. 2) space group (Z = 2) with respective unit cells: a = 11.570(4), b = 15.122(2), c = 9.919(3) Å, α = 79.86(4), β = 64.87(3), γ = 97.94(4)°; and α = 11.571(16), b = 15.078(2), c = 9.869(2) Å, α = 100.16(1), β = 64.97(1), γ = 82.10(1)°. Both structures consist of puckered 6-membered rings formed by coordination of the disulfide ligands via two sulfur atoms to the metal center. The rings lie in distorted boat conformations with the prows occupied by one sulfur and one phosphorus and the metal atoms in one side.Item Preparation and 31P NMR characterization of N-bonded complexes of platinum(II) with a phosphadithiatriazine: x-ray structure of trans-PtCl2(Pet3)(η1-N-Ph2PS2N3)(1992) Chivers, Tristram; Hilts, Robert; Krouse, Ian H.The reaction of Ph2PS2N3 with [Pt2(μ-Cl)2(PEt3)4][BF4]2 or [PtCl2(PEt3)]2, in dichloromethane at 23° C produces the 1:1 adducts cis-[PtCl(PEt3)2(Ph2PS2N3)][BF4], 3, and trans-[PtCl2(PEt3)(Ph2PS3N2)], 4, respectively, in good yields. The 31P NMR data for 3 and 4 indicate that (i) the platinum is attached to a nitrogen atom adjacent to phosphorus in both these adducts, (ii) the PEt3 ligands in 3 are in mutually cis positions, and (iii) the PEt3 ligand in 4 is trans to the heterocyclic nitrogen. These structural features were confirmed by an X-ray analysis of 4. Crystals of 4 are monoclinic, space group P21/c, with a = 14.920(3) Å, b = 8.966(5) Å, c = 19.103(5) Å, β = 109.32(2)°, V = 2411.6(16) Å3, and Z = 4. The least-squares refinement with anisotropic thermal parameters for all non-hydrogen atoms converged at R = 0.050 and Rw = 0.053. The Pt—N bond length is 2.122(15) Å and the coordinated nitrogen atom is lifted ca. 0.63(2) Å out of the plane containing the other heterocyclic ring atoms. The attachment of a platinum(II) centre to the PN3S2 ring perturbs the S—N bond lengths significantly. The S—N distance involving the coordinated nitrogen is 1.672(16) Å, while the other S—N distances are 1.631(19), 1.555(19), and 1.562(19) Å, indicative of a localized sulfur diimide (-N=S=N-) structure. The UV–visible spectra of 3 and 4 in CH2Cl2 exhibit absorption bands at 514 and 528 nm, respectively, but dissociation of these adducts to give the free ligand Ph2PS2N3 occurs readily in dilute solution.Item Formation, x-ray structure, and deprotonation of an S,S'-methylene-bridged P2N4S2 ring(1992) Chivers, Tristram; Cowie, Martin; Edwards, Mark; Hilts, RobertThere is an extensive chemistry of binary sulfur-nitrogen (S- N) anions, several of which are shown only in coordination complexes with metals. Although there is polarographic evidence for the formation of S4N4(2-) at low temperatures, this dianion has only been characterized in Ira and Pt5b complexes as a tridentate (N,S,S’) ligand formed by insertion of the metal into an S-N bond of S4N4. Anions of diphosphadithiatetrazocines 1 are unknown, but Pt0 or Pd0 compounds readily undergo oxidative addition with these norganic heterocycles to give ŋ2- S4ZS1-metal complexes.(6)Item Preparation, spectroscopic and structural characterization of η1-N and η2-Se,Se′ complexes of a P2N4Se2 ring(1992) Chivers, Tristram; Doxsee, Daniel D.; Hilts, Robert; Meetsma, Auke; Parvez, Masood; Grampel, Johan C. van deThe reaction of 1,5-Ph4P2N4Se2, 1, prepared by the treatment of Ph2PN2(SiMe3)3 with a mixture of SeCl4 and Se2Cl2 in acetonitrile, with [PtCl2(PEt3)]2 gives the adducts [PtCl2(PEt3)]n[η1-N-Ph4P2N4Se2](2, n- 1; 3, n- 2) in which the P2N4Se2 ring is shown by an X-ray structural determination of 3 to contain a transannular Se–Se interaction; the oxidative addition of 1 or 2 to Pt(C2H4)(PPh3)2 produces the corresponding η2-Se,Se′ complexes.Item Synthesis and reactions of the [(.mu.-Ph2P)Fe2(CO)6]- anion(1992) Seyferth, Dietmar; Brewer, Karen S.; Wood, Timothy G.; Cowie, Martin; Hilts, RobertThe action of 2 molar equiv of LiBE^H on 0i-CH3C=O)0i-Ph2P)Fe2(CO)6 gives a reactive species which IR spectroscopic evidence suggests to be Li[(/i-Ph2P)Fe2(CO)6]. This species reacts with acid halides, RC(0)C1, Me2NC(S)Cl, Me2P(S)Cl, and chlorophosphines; neutral products of type 0t-E)0i-Ph2P)Fe2(CO)6 (E = RC=0, Me2NC=S, Me2P=S, R^) were obtained in good yield. Reaction with CS2 and RNCS gave anionic products, 0t-SC==S)0t-Ph2P)Fe2(CO)6 and Ot-RÑO=S)Ot-Ph2P)Fe2(CO)6. The [Oi-Ph2P)Fe2(CO)8]~ reagent is much more reactive than the known [^-CO)(p-Ph2P)Fe2(CO)6]~. The structure of (µCH3)2P==S)0t-PhS)Fe2(CO)6 (18b) has been determined by X-ray techniques. Compound 18b crystallizes in the orthorhombic space group P212121 with o = 12.494 (2) k,b- 17.075 (2) Á, c = 8.7909 (9) k,V1944.7 (7) Á3, and Z = 4. The two Fe(CO)3 groups in the complex are bridged by the benzenethiolate and the dimethylphosphino sulfide groups, the latter of which is S-bound to one metal and P-bound to the other. Within the SPMe2 ligand the P—S distance of 2.030 (2) A lies intermediate between that of a single (2.18 A) and a double (1.95 A) bond.Item Reactions of 2-furyl, 2-thienyl, and N-methyl-2-pyrrolyl mercurials with [Et3NH][(.mu.-CO)(.mu.-RS)Fe2(CO)6] complexes. Synthesis of Fe2(CO)6 complexes with bridging .eta.1:.eta.2-furyl and thienyl ligands(1992) Seyferth, Dietmar; Anderson, Lea L.; Villafane, Fernando; Cowie, Martin; Hilts, RobertItem Preparation and NMR characterization of N1-bonded platinum (II) and palladium(II) adducts of eight-membered heterocyclic thiazenes(1992) Hilts, Robert; Chivers, TristramItem Multimode coordination chemistry of [R2P(X)CHnP(Y)R'2](2-n)- ligands (X, Y = O, S, Se; n = 1, 2). Synthesis and phosphorus-31 NMR spectroscopy of platinum complexes(1992) Berry, David E.; Browning, Jane; Dixon, Keith R.; Hilts, Robert; Pidcock, AlanReactions of the bis(phosphine chalcogenides) CH2|P(X)R2l|P(Y)R'2l (X, Y = O, S, Se) and their derived anions [CH|P-(X)R2)lP(Y)R'2l]" with chloroplatinum complexes PtCl42", [Pt2Cl4(PEt3)2], or [Pt2Cl2(PEt3)4]2+ result in a wide variety of coordination complexes. For example, when R = R' = Ph and X = Y = S, the following are all accessible in high yield: [PtCl(PEt3){CH2(P(S)Ph2)2-S^|]+, [PtCl(PEt3)iCH(P(S)Ph2)2-C,S|], [PtCl(PEt3)|CH(P(S)Ph2)2-S^|], [Pt(PEt3)2|CH2(P(S)-Ph2)2)-5^i]2+, [Pt(PEt3)2(CH(P(S)Ph2)2-C,S|]+, [PtCl2lCH2(P(S)Ph2)2-S^l], [Pt|CH2(P(S)Ph2)2-.S„S|2]2+, and [Pt(CH(P-(S)R2)2-C^|2]· A more limited range of complexes is also reported for X = Y = O, X = Y = Se, and X = O, Y = S. In general, the ligands exhibit at least five different coordination modes: (i) Bidentate X,Y coordination of neutral ligands; (ii) bidentate X,Y coordination of the anionic ligands; (iii) bidentate C,X coordination of the anions in a strained four-membered ring; (iv) monodentate C coordination of the anions; (v) complex C,S bridging mode involving a dianionic ligand and two metal centers. Interconversion reactions and characteristic 31P NMR spectroscopy are described for all of the coordination modes, including dynamic NMR studies of the C,X modes. These last modes all exhibit some degree of fluxional behavior, involving an exchange of coordinated and noncoordinated P=X groups in essentially a classic “bimolecular” substitution reaction, except that the incoming ligand is actually part of one of the existing ligands.Item Coordination chemistry of [CH2(PPh2) (P(Y)R2)] and [CH(PPh2)(P(Y)R2)]−, Y = S or Se, R = Ph or tBu: rhodium, iridium and ruthenium complexes; 13C 31P, and 77 Se NMR studies; and the crystal and molecular structures of [Ir(cod)CH2(PPh2)(P(S)tBu2)-P,S]BF4 · CHCl3, [Rh(cod)CH2(PPh2)(P(S)tBu2)-P,SClO4 · CH2Cl2 [Rh(cod)CH(PPh2) (P(S)Ph2)-P,S] and [RuCl2(p-cymene)CH2(PPh2)(P(S) Ph2) -P] · CH2Cl2(1992) Browning, Jane; Bushnell, Gordon W.; Dixon, Keith R.; Hilts, RobertReactions of the chloro-bridged complexes, [M2Cl2(cod)2], M Ir or Rh, COD cyclooctadiene, with CH2(PPh2)(P(Y)R2), Y S or Se, R Ph or tBu, provide a synthetic route to the cations, [M(cod)(CH2(PPh2)(P(Y)R2)-P,S]+, which are isolated as fluoroborate or perchlorate salts. Treatment of these products with sodium hydride results in facile deprotonation to the neutral complexes, [M(cod)CH(PPh2)(P(Y)Ph2)-P,S)], and when Y S, the neutral complexes are also accessible via reactions of [M2Cl2(cod)2] with Li[CH(PPh2)(P(S)R2)]. Reactions of the cations, [M(cod)CH2(PPh2)(P(S)tBu2)-P,S)]+ with other ligands, Lg (CO)2, (CNtBu)2, or bis(diphenylphosphino)methane (dppm), result in displacement of cod to form [M(Lg)(CH2(PPh2)(P(S)tBu2)-P,S]+. Ruthenium complexes of CH2(PPh2)(P(S)Ph2) are accessiblevia similar bridge cleavage reactions using [Ru2Cl4L2], L benzene or p-cymene. These complexes are characterized by complete 13C, 31P, and 77Se nuclear magnetic resonance (NMR) studies and by four crystal structure determinations. The complexes [Ir(cod)(CH2(PPh2)(P(S)tBu2)-P,S]BF4·CHCl3 (1), [Rh(cod)(CH2(PPh2)(P(S)tBu2)-P,S]ClO4·CH2Cl2 (2), [Rh(cod)(CH(PPh2)(P(S)Ph2-P,S] (3) and [RuCl2(p-cymene)(CH2(PPh2)(P(S)Ph2)-P]· CH2Cl2 (4) crystallize in the P (No. 2) space group (Z 2) with respective unit cells: a = 12.307(7) Å, b = 14.743(8) Å, c = 10.877(6) Å, α =74.42(5)°, β = 107.65(6)°, γ = 105.47(5)°; a = 12.163(1) Å, b = 14.56(1) Å, c = 10.560(1) Å, α = 77.69(1)°, β = 74.54(1)°, γ = 77.01(1)°; a = 10.650(4) Å, b = 13.327(4) Å, c = 10.419(3) Å, α = 90.60(3)°, β = 102.64(3)°, γ = 83.15(3)°; a = 11.217(2) Å, b 17.124(3) Å, c = 10.412(2) Å, α = 90.58(1)°, β = 112.29(2)°, γ = 97.53(2)°. Complexes 1–3 all contain bidentate P,S-bonded ligands occupying two coordination positions of an approximately square planar metal centre. In each case, the coordination is completed by two double bonds of a cod ligand. In contrast, complex 4 contains a monodentate P-bonded ligand.Item Preparation and nuclear magnetic resonance characterization of N-bonded complexes of platinum(II) with phosphorus-nitrogen rings containing three-coordinate chalcogens: x-ray structure of [PtCl2(PEt3)]2(Ph4P2N4Se2Et2)(1993) Chivers, Tristram; Doxsee, Daniel D.; Hilts, Robert; Parvez, MasoodThe reaction of 1,5-Ph4P2N4S2Ph2 with [PtCl2CPEt3)]2 in chloroform at 60 °C produces the 1:1 adduct trans-PtCl2(PEt3)(Ph4P2N4S2Ph2) in which the platinum is attached to a nitrogen atom on the basis of 31P nmr spectroscopy. By contrast, the corresponding reactions of 1,5-Ph4P2N4Se2R2 (R = Me, Et, Ph) produce the 2:1 adducts [PtCl2(PEt3)]2(Ph4P2N4Se2R2) (7a, R = Me; 7b, R = Et; 7c, R = Ph) which have been characterized by 1H, 31P and 77Se nmr spectroscopy and, in the case of 7b, by X-ray crystallography. Crystals of 7b are monoclinic, space group C2/c, with a = 27.803(7) Å, b = 12.378(7) Å, c = 15.752(8) Å, β = 115.49(2)°, V = 4893(3) Å3, and Z = 4. The least-squares refinement with anisotropic thermal parameters for all non-hydrogen atoms converged at R = 0.037 and Rw = 0.022. The platinum centres in 7b are attached to distal nitrogen atoms of the disordered P2N4Se2 ring. The reaction of the six-membered ring Ph4P2N3SPh with [PtCl2(PEt3)]2 in dichloromethane at 23 °C occurs in a regiospecific manner to give the 1:1 adduct PtCl2(PEt3)(Ph4P2N3SPh) in which, on the basis of 31P nmr spectroscopy, the platinum is coordinated to a nitrogen atom between phosphorus and sulfur.Item Solid state and solution structures of dimeric organolithium derivatives of a P2N4S2 ring(1993) Chivers, Tristram; Edwards, Mark; Hilts, Robert; Parvez, Masood; Vollmerhaus, RainerAn X-ray structural determination of the dimer [Li(Ph4P2N4S2Ph)-THFl2 (THF = tetrahydrofuran) reveals a step-shaped structure; 7Li and 31P NMR investigations of [Li(Ph4P2N4S2R)-THFl2 (R = Me, But, Ph), as a function of temperature and concentration, in THF solution show that this dimer is fluxional and indicate the presence of a second dimeric species.Item Preparation and phosphorus-31 and selenium-77 NMR spectra of platinum and palladium complexes of a P2N4Se2 ring(1993) Chivers, Tristram; Doxsee, Daniel D.; Hilts, Robert; Parvez, MasoodThe reaction of 1,5-Ph4P2N4Se2 with Pt(PPh&(CH2=CH2) or Pd(PPh3)l in toluene at 0 OC produces the 92- Se,Se'-bonded complexes M(PPh3)2( 1,5-Ph4P~N4Sez) (2a, M = Pt; 2b, M = Pd) characterized by their 3IP and "Se NMR spectra. Simulation of the 77Se NMR spectra gave detailed coupling information for 2a and 2b. Heating 2a or 2b in boiling toluene produces the corresponding ~2-Se,N-p,r11-Se'-bonded dimers [M(PPh3)( 1,5-Ph&N4- Sez)12 (3a, M = Pt; 3b, M = Pd). Variable-temperature 31P NMR spectra of 3a reveal a fluxional process which is proposed to involve a [ 1,3]-metallotropic shift. The reaction of 1,5-Ph4P2N4Se2 with [PtC12(PEt3)]2 in CHzCl2 produces the #-N-bonded adducts [PtClZ(PEt3)],(1,5-Ph4PzN4Se2) (4a, n = 1; 5, n = 2). The two PtC12(PEt3) groups in 5 are attached to distal nitrogen atoms of the P2N4Se2 ring, which retains a folded structure with d(Se-Se) = 2.594 A. Treatment of 4a with Pt(PPh3)2(CHyCH2) produces the pZ,s3-Se,Se',N-bonded complex Pt(PPh3)z( 1,s- PhP2Nfie2) [PtC12(PEt3)] identified by "PNMR spectroscopy. Reaction of [Li[Ph&NBe2Ph](THF)]z, generated from the combination of 1,5-Ph4P~N4Sez and phenyllithium in THF, with cis-PtCl~(PEt3)~ yields the +Se-bonded complex trans-PtCl(PEt3)z(PhdP2N&e2Ph)(7a). Variable temperature 31P NMR spectra of 7a reveal a two-site exchange process involving the two PEt3 ligands, which is proposed to occur via rotation about the PtSe bond. Line-fitting analysis yielded the thermodynamic parameters for this process.