Raymond J. Haines

Reactions of metal carbonyl derivatives : IV. Bridged sulphido derivatives of iron carbonyl

Abstract The secondary alkanethiols RSH (R = i-C3H7 and s-C4H9) react with Fe3(CO)12 in refluxing benzene to afford initially Fe3(CO)9(H)(SR) which reacts further with the thiol to yield [Fe(CO)3SR]2. The corresponding reaction involving the tertiary alkanethiol t-C4H9SH similarly affords Fe3(CO)9(H)(S-t-C4H9). Prolonged heating of a benzene solution of this thiol and Fe3(CO)12 affords four products, viz. [Fe(CO)3S-t-C4H9]2, Fe3(CO)9(S-t-C4H9)2, Fe4(CO)12(S)(S-t-C4H9)2 and Fe3(CO)9S2. It is established that compounds of the type [Fe(CO)3SR]2 are synthesised in highest yield by reacting Fe2(CO)9 with the appropriate thiol in benzene at room temperature. Structures for the tri- and tetranuclear compounds containing bridging sulphido and where appropriate bridging hydrido groups are proposed based on the infrared, NMR and mass spectroscopic data. The mass spectra of the compounds [Fe(CO)3SR]2 (R = i-C3H7 and t-C4H9), Fe3(CO)9(H)(SR1) (R1 = i-C3H7, s-C4H9 and t-C4H9), Fe3(CO)9(S-t-C4H9)2 and Fe4(CO)12(S)(S-t-C4H9)2 are discussed.

Reactions of metal carbonyl derivatives : VII. Reactions of chloro- and iododicarbonyl-π-cyclopentadienyliron with some tertiary phosphines and phosphites☆☆☆

Abstract The tertiary alkyl phosphites P(OR) 3 (R = CH 3 , C 2 H 5 , n-C 4 H 9 and C 3 H 5 ) react with π-C 5 H 5 Fe(CO) 2 Cl in benzene to give in addition to neutral π-C 5 H 5 Fe(CO)P(OR) 3 Cl and ionic [π-C 5 H 5 Fe(CO) 2 P(OR) 3 ]Cl complexes, neutral phosphonate derivatives of formula π-C 5 H 5 Fe(CO) 2 [P(O)(OR) 2 ] and π-C 5 H 5 Fe(CO)-[P(OR) 3 ][P(O)(OR) 2 ]. The corresponding reactions involving the tertiary phosphonite P(OC 3 H 5 ) 2 C 6 H 5 and the tertiary phosphinite P(OC 3 H 5 )(C 6 H 5 ) 2 yield similar type products. In contrast compounds of the type [π-C 5 H 5 Fe(CO)P(OR) 3 ]I are the sole products from the reactions of P(OR) 3 (R = CH 3 and C 2 H 5 ) with π-C 5 H 5 Fe(CO) 2 I. The formation of π-C 5 H 5 Fe(CO) 2 [P(O)(OR) 2 ] is shown to occur via [π-C 5 H 5 Fe(CO) 2 P(OR) 3 ]Cl as intermediate and to involve a Michaelis-Arbuzov rearrangement. The reactions of π-C 5 H 5 Fe(CO) 2 X (X = Cl and I) with the tertiary phosphines PR 3 (R = C 2 H 5 and C 4 H 9 ) are also described.

Condensation as well as trinuclear products from the reaction of triruthenium dodecacarbonyl with diphenylphosphine

Abstract The reaction of [Ru3(CO)12] with PPh2H in toluene under reflux affords a range of products, the nature and yields of which depend on the reaction times and the molar ratios employed. Compounds isolated include not only the trinuclear species [Ru3(μ2-PPh2)2(μ2-H)2(CO)8], [Ru3(μ2-PPh2)3(μ2-H)(CO)7], [Ru3(μ2-PPh2)3(μ2-H)(CO)6(PPh2H)], [Ru3(μ3-PPh)(μ-H)2(CO)9] and [Ru3(μ-PPh)(μ-PPh2)2(CO)7] but also condensation products, such as [Ru4(μ4-PPh)2(μ2-CO)(CO)10], [Ru5(μ4-PPh)(CO)15], [Ru6(μ4-PPh)2(μ3-PPh)2(CO)12] and [Ru7(μ4-PPh)2(CO)18], previously isolated from the reaction of [Ru3(CO)12] with PPhH2, as well as the highly unusual octaruthenium derivative [Ru8(μ8-P)(μ2-η1,η6-CH2Ph)(μ2-CO)2(CO)17] and the fragmentation product [Ru2(μ-PPh2)2(CO)6]. The molecular stereochemistries of [Ru2(μ-PPh2)2(CO)6], [Ru3(μ2-PPh2)3(μ2-H)(CO)7], [Ru3(μ2-PPh2)3(μ2-H)(CO)6(PPh2H)] and [Ru8(μ8-P)(μ2-η1,η6-CH2Ph)(μ2-CO)2(CO)17] have been established by X-ray crystallography. The eight ruthenium atoms in the latter adopt a square antiprismatic geometry and encapsulate a phosphorus atom derived from the diphenylphosphine. The benzyl group in this compound exhibits an unusual mode of coordination with the benzene ring functioning as a hexahapto ligand towards one of the ruthenium atoms and with the benzylic carbon bonding directly to an adjacent ruthenium atom.

Stabilisation of [Fe2(CO)9] and [Ru2(CO)9] bu substitution with bridging diphosphorus ligands

Abstract Reaction of [Fe 2 (CO) 9 ] with a half molar amount of R 2 PYPR 2 (Y = CH 2 , R = Ph, Me, OMe or OPr i ; Y = N(Et), R = OPh, OMe or OCH 2 ; Y = N(Me), R = OPr i or OEt) leads to the ready formation of a product which on irradiation with ultraviolet light rapidly decarbonylates to the heptacarbonyl derivative [Fe 2 (μ-CO)(CO) 6 {μ-R 2 PYPR 2 }]. Treatment of the latter with a slight excess of the appropriate ligand results, under photochemical conditions, in the formation of the dinuclear pentacarbonyl complex [Fe 2 (μ-CO)(C)) 4 {μ-R 2 PYPR 2 } 2 ] but under thermal conditions in the formation of the mononuclear species [Fe(CO) 3 {R 2 PYPR 2 }]. Reaction of [Ru 3 (CO) 12 ] with an equimolar amount of (RO) 2 PN(R′)P(OR) 2 (R′ = Me, R = Pr i or Et; R′ = Et, R = Ph or Me) under either thermal or photochemical conditions produces [Ru 3 (CO) 10 {μ-(RO) 2 PN(OR) 2 }] which reacts further with excess (RO) 2 PN(R′)P(OR) 2 on irradiation with ultraviolet light to afford the dinuclear compound [Ru 2 (μ-CO)(CO 4 {μ-(RO) 2 PN(R′)P(OR) 2 } 2 ]. The molecular structure of [Ru 2 (μ-CO)(CO) 4 {μ-(MeO) 2 PN(Et)P(OMe) 2 } 2 ], which has been determined by X-ray crystallography, is described.

Reactions of metal carbonyl derivatives II. Ditertiary phosphine and arsine derivatives of tetracarbonyldi-π-cyclopentadienyldiiron☆☆☆★

Abstract The ditertiary phosphine and arsine ligands L = (C6H5)2P(CH2)nP(C6H5)2 (n = 1,2,3), cis-(C6H5)2PC2H2P(C6H5)2, (C6H5)2PN(C2H5)P(C6H5)2 and (C6H5)2As(CH)2nAs(C6H5)2 (n = 1, 2) have been shown to react with tetracarbonyldi-π-cyclopentadienyldiiron in benzene when the solution is refluxed or irradiated with ultraviolet light at room temperature to afford derivatives of the type [π-C5H5Fe(CO)]2L. Analogous products are similarly obtained from the reactions of (C6H5)2-P(CH2)nP(C6H5)2 (n = 1, 2), cis-(C6H5)2PC2H2P(C6H5)2 and (C6H5)2PN(C2H5)P(C6H5)2 with [π-CH3C5H4Fe(CO)2]2. On the basis of infrared spectroscopic evidence it is shown that the two terminal carbonyl groups in [π-RC5H4Fe(CO)2]2(R = H, CH3) have been replaced by these donor ligands and a structure for the new products is proposed. The infrared and nuclear magnetic resonance spectra are discussed.

Oxidation of diphosphazane-bridged derivatives of diruthenium nonacarbonyl by silver(I) salts in protic solvents: synthesis, structural characterization and protonation of the adduct [Ru2{µ-η2-OC(O)}(CO)4{µ-(RO)2PN(Et)P(OR)2}2](R = Me or Pri) involving a novel mode of co-ordination of carbon dioxide

Treatment of [Ru2(µ-CO)(CO)4{µ-(RO)2PN(Et)P(OR)2}2](R = Me or Pri) with AgSbF6 in methanol, ethanol or tetrahydrofuran–water resulted in the formation of the solvento species [Ru2(CO)5(R′OH){µ-(RO)2PN(Et)P(OR)2}2][SbF6]2 which is isolable for R′= H but which spontaneously deprotonates to the alkoxycarbonyl-bridged derivative [Ru2{µ-η2-OC(OR′)}(CO)4{µ-(RO)2PN(Et)P(OR)2}2]SbF6 for R′= Me or Et. The aqua species [Ru2(CO)5(H2O){µ-(RO)2PN(Et)P(OR)2}2][SbF6]2 was readily deprotonated in consecutive steps by appropriate bases to afford respectively the hydroxycarbonyl-bridged species [Ru2{µ-η2-OC(OH)}(CO)4{µ-(RO)2PN(Et)P(OR)2}2]SbF6 and the adduct [Ru2{µ-η2-OC(O)}(CO)4{µ-(RO)2PN(Et)P(OR)2}2] in which the carbon dioxide molecule adopts a novel bridging co-ordination mode; this deprotonation is reversible and treatment of the latter with HBF4·OEt2 leads to stepwise regeneration of the aqua species. The co-ordinated water molecule in [Ru2(CO)5(H2O){µ-(PriO)2PN(Et)P(OPri)2}2][SbF6]2 was readily displaced by acids HA derived from conjugate bases with potential co-ordinating properties such as thiolate ions R″S–(R″= H or Ph) or carboxylate ions R‴CO2–(R‴= H, Me, Ph or CF3), to produce monocationic pentacarbonyl species of the type [Ru2A(CO)5{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6; detection of an intermediate, presumably [Ru2(CO)5(HA){µ-(PriO)2PN(Et)P(OPri)2}2][SbF6]2, was possible for HA = HCO2H and MeCO2H. The sulfido derivatives [Ru2(SR″)(CO)5{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6(R″= H or Ph) rapidly decarbonylate in solution to afford the tetracarbonyl products [Ru2(µ-SR″)(CO)4{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6 in which the sulfido group bridges the two ruthenium atoms. On the other hand the carboxylato derivatives [Ru2{OC(O)R‴}(CO)5{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6(R‴= H, Me, Ph or CF3) are stable to decarbonylation in solution at room or elevated temperatures but can be decarbonylated to the carboxylato-bridged products [Ru2{µ-η2-OC(R‴)O}(CO)4{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6 by irradiation with ultraviolet light. The water molecule in [Ru2(CO)5(H2O){µ-(PriO)2PN(Et)P(OPri)2}2][SbF6]2 was also readily displaced by the conjugate bases of the above acids HA, but in contrast to that observed for the carboxylic acids R‴CO2H (R‴= H, Me or Ph), reaction of the aqua species with the corresponding carboxylate ions R‴CO2– led to direct formation of the carboxylato-bridged species [Ru2{µ-η2-OC(R‴)O}(CO)4{µ-(PriO)2PN(Et)P(OPri)2}2]SbF6. Possible mechanisms for the formation of the various products are discussed as are the structures of [Ru2(CO)5(H2O){µ-(PriO)2PN(Et)P(OPri)2}2][SbF6]2·OCMe2, [Ru2{µ-η2-OC(OEt)}(CO)4{µ-(MeO)2PN(Et)P(OMe)2}2]SbF6, [Ru2{µ-η2-OC(Me)O}(CO)4{µ-(PriO)2PN(Et)P(OPri)2}2]PF6 and [Ru2{µ-η2-OC(O)}(CO)4{µ-(PriO)2PN(Et)P(OPri)2}2], established X-ray crystallographically.

Reaction of triruthenium dodecacarbonyl with bis(dimethylphosphino)methane, bis(diphenylphosphino)methane and bis(diphenylphosphino)-ethylamine under photochemical conditions

Abstract The photochemical reactions of [Ru 3 (CO) 12 ] with the diphosphorus ligands Me 2 PCH 2 PME 2 , Ph 2 PCH 2 PPh 2 and Ph 2 PN(Et)PPh 2 have been found to give tri-, di- or mono-nuclear products, depending on the reaction conditions and the ligand involved. Products isolated include [Ru 3 (CO) 10 [μ-R 2 PYPR 2 ] (Y = CH 2 , R = Me or Ph; Y = N(Et), R = Ph), [Ru 3 (CO) 8 [μ-R 2 PYPR 2 ] 2 ] (Y = CH 2 , R = Me or Ph), [Ru 3 (CO) 6 [μ-R 2 PYPR 2 ] 3 ] (Y = CH 2 , R = Me or Ph), [Ru 2 (μ-CO)(CO) 4 [μ-Ph 2 PCH 2 PPh 2 ] 2 ] and [Ru(CO) 3 [Ph 2 PN(Et)PPh 2 ]. An X-ray crystallographic study has revealed that the diphosphazane ligand in [Ru 3 (CO) 10 [η-Ph 2 PN(Et)PPh 2 ] is coordinated equatorially and that the Ru-Ru edge which it bridges is ca. 0.06 A shorter than the average of the other two edges.

Dicopper(I) complexes of the novel phosphorusbipyridyl ligand 6-diphenylphosphino-2,2′-bipyridyl

Abstract Reaction of 6-diphenylphosphino-2,2′-bipyridine (Ph2Pbipy) with copper(I) precursors such as [Cu(MeCN)4]+ and [Cu(2,2′-bipy)(MeCN)2]+ affords dinuclear phosphorusbipyridyl ligand-bridged dicopper products and in particular [Cu2(μ-Ph2Pbipy)2 (MeCN)2]2+ (1 and [Cu2(2,2′-bipy)(μ-Ph2Pbipy)2]2+ (2), respectively. The ligand coordinates head-to-tail in 1, and head-to-head in 2, as established by single crystal X-ray diffraction studies.

Reactions of metal carbonyl derivatives. Part IX. The synthesis, infrared spectra, and Mössbauer spectra of some tertiary and ditertiary phosphine, arsine, and stibine derivatives of bis(µ-methylsulphido-, -ethylsulphido-, and -phenylsulphido-tricarbonyliron)

The reactions of [Fe(CO)3SR]2(R = Me or Et) with the ditertiary phosphines L = Ph2P·[CH2]N·PPh2(n= 1 or 2), cis-Ph2P·C2H2·PPh2 and Ph2P·NEt·PPh2 and the ditertiary arsines L = Ph2As·[CH2]n·AsPh2(n= 1 or 2) under various experimental conditions have been studied. A number of different types of products have been isolated. These include [Fe2(CO)5L(SR)2] and [Fe(CO)2LSR]2 in which the ligands are monodentate, [{Fe(CO)2SR}2L] in which the ligand bridges two iron atoms, [Fe(CO)3(SR)2Fe(CO)L] in which the ligand is chelated to a single iron atom and [Fe2(CO)3L2(SR)2] in which one ligand is bidentate and the other monodentate. The nature of the product is shown to depend on the ligand and the reaction conditions. The reactions of [Fe(CO)3SMe]2 with the ligands L′= PEt3, PPh3, P(OMe)3, AsPh3, and SbPh3 have also been studied and the mono-substituted [Fe2-(CO)5L′(SMe)2], bis-substituted [Fe(CO)2L′SMe]2, and tris-substituted [Fe2(CO)3L′3(SMe)2] derivatives have been isolated.Mossbauer and i.r. spectroscopy have been used to elucidate the structures of the above derivatives as well as those of the products of the reactions of [Fe(CO)3SPh]2 with various tertiary and ditertiary phosphines. Systematic variations in the chemical isomer shift and quadrupole splitting are discussed in relation to the bonding in these compounds.

Tri-, tetra-, penta-, and hexa-nuclear phenylphosphinidene-capped products from the reaction of dodecacarbonyltriruthenium with phenylphosphine: crystal structures of [Ru4(µ4-PPh)2(µ-CO)(CO)10], [Ru5(µ4-PPh){µ-PPh(OPrn)}(µ-H)(CO)13], [Ru6(µ4-PPh)2(µ3-PPh)2(CO)12], and [Ru6(µ4-PPh)3(µ3-PPh)2(CO)12]

The reaction of [Ru3(CO)12] with PPhH2 in toluene under reflux affords a range of products, the nature and yields of which are dependent on the reaction times and the molar ratios employed. Compounds isolated and characterised include not only the trinuclear derivatives [Ru3(µ-PPhH)(µ-H)(CO)10], [Ru3(µ3-PPh)(µ-H)2(CO)9], and [Ru3(µ3-PPh)2(CO)9] but the tetra-, and penta-, and hexanuclear species [Ru4(µ4-PPh)2(µ-CO)(CO)10], [Ru4(µ4-PPh)2(µ-PPhH)2(CO)8], [Ru5(µ4-PPh)(CO)15], [Ru6(µ-PPh)2(CO)n](n= 14 or 15), [Ru6(µ4-PPh)2(µ3-PPh)2(CO)12], and [Ru6(µ4-PPh)3(µ3-PPh)2(CO)12] as well as the pentanuclear by-product [Ru5(µ4-PPh){µ-PPh(OPrn)}(µ-H)(CO)13]. Crystal-structure determinations have revealed that [Ru4(µ4-PPh)2(µ-CO)(CO)10] contains an approximately square-planar array of ruthenium atoms capped on both sides by phenylphosphinidene ligands, that [Ru6(µ4-PPh)2(µ3-PPh)2(CO)12] and [Ru6(µ4-PPh)3(µ3-PPh)2(CO)12] have distorted trigonal-prismatic skeletal geometries, and that the ruthenium atom framework in [Ru5(µ4-PPh){µ-PPh(OPrn)}(µ-H)(CO)13] adopts a square-pyramidal configuration with the basal plane being capped by a phenylphosphinidene ligand and a basal edge being bridged by a phosphido group.