Jonathan N. Wingfield

Transition-metal complexes containing phosphorus ligands. Part XIII. Dialkyl phenylphosphonite and alkyl diphenylphosphinite derivatives of silver, gold, and the platinum metals

Reactions between metal halides, metal carbonyl halides, or metal olefin halides and dialkyl phenylphosphonite, P(OR)2Ph, or alkyl diphenylphosphinite, P(OR)Ph2, ligands (R = Me, Et) performed in polar or aromatic solvents afford a general route to an extensive series of uncharged complexes. Compounds isolated in this way include RuCl2(CO)2L2, RuCl2(CO)L3, OsCl2(CO)2L2, IrHCl2L3, cis-PdCl2L2, cis-PtCl2L2, cis-PtBr2L2[L = P(OR)Ph2, P(OR)2Ph; R = Me, Et], AgCl[P(OEt)Ph2]2, AgClL′[L′= P(OR)2Ph, P(OMe)Ph2], and AuCl[P(OEt)Ph2]. 1H and 31P N.m.r. spectra are presented and discussed.

Preparation of potential macroligands for alkali-metal ions using open-chain polyether carboxylic acids and tricarbonylbis(triphenylphosphine)ruthenium. X-Ray crystal structure of dicarbonylbis[1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethanato(1–)]bis(triphenylphosphine)ruthenium(II)

The preparation and X-ray crystal structure of the title compound is described. The compound crystallizes in the triclinic space group P(no. 2) with unit-cell dimensions a= 9.677(2), b= 23.161 (6), c= 15.432(5)A, α= 92.91 (2), β= 91.29(4), γ= 102.16(3), and Z= 2. The structure was refined to a final R factor of 0.094 for 4 681 reflections. The ruthenium ion is octahedrally co-ordinated by two mutually cis carbonyl ligands, two mutually trans phosphine ligands, and two mutually cis L ligands, [1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethanato(1–)] each bound to ruthenium by one oxygen of the carboxylate group. The benzene rings of the phosphine ligands are staggered, and prevent close approach of the two L ligands required to form an oxygen cavity suitable for complexation with alkali metals.

Co-ordination of alkali metals by open-chain polyethers in transition-metal complexes. Part 3. The X-ray structures of 1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethane (HL) and its acid salt, KHL2, a possible intermediate in the formation of Co(KL2)2

The X-ray crystal structures of the title compound, HL, and its acid salt, KHL2, are reported and their hydrogen-bonding schemes compared. HL crystallises in an extended form with intermolecular hydrogen bonding linking the molecules in chains; there are no phenol to carboxyl hydrogen linkages. KHL2 contains HL2– units where the two L ligands are held together by one strong hydrogen bond between the carboxyl groups across a centre of symmetry, and two weaker phenol to carbonyl interactions. The HL2– units then form sandwiches round potassium in pentagonal antiprism co-ordination to give a step polymer. The structure of KHL2 is compared with those of Co(KL2)2 and Co(RbL2)2, and its role as a possible intermediate in the formation of Co(KL2)2 discussed.

X-Ray analysis of the [1-(o-carboxymathoxyphenoxy)-2-(o-hydroxyphenoxy)ethanato-sodium] tetramer, a sodium–oxygen cubane structure

The crystal structure of the title compound shows a tetrameric association, with alternating sodium and oxygen atoms at the corners of a cube, pentagonal bipyramidal co-ordination round each sodium, and each ligand in the tetramer co-ordinating to all four sodium ions; the hydroxy acid polyether ligands, L, are arranged in hydrogen-bonded dimmer pairs, as found in other L complexes.

Co-ordination of alkali metals by open-chain polyethers in transition-metal complexes. Part 2. An explanation for alkali-metal selectivity from the X-ray and molecular structure of tetrakis[1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethanato(1–)]dirubidiumcobalt(II) and comparison with the dipotassium analogue

The synthesis and X-ray crystal structure of the title compound [Co(L2Rb)2], containing the tifunctional centre Rb–Co–Rb, is reported and compared with the analogous [Co(L2K)2] structure. The selectivity of the moiety [CoL4]2– between alkali metals and, in particular, for potassium is discussed on the basis of this comparison. Crystals of [Co(L2Rb)2] are triclinic, a= 14.352(4), b= 14.911(3), c= 16.772(3), α= 93.16(2), β= 106.75(2), γ= 110.91(2)°, and Z= 2. The structure was refined to R= 0.055 for 3 585 reflections.

Co-ordination of alkali metals by open-chain polyethers in transition-metal complexes. Part 1. X-Ray crystal and molecular structure of tetrakis[1-o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethanato(1–)]dipotassiumcobalt(II), a trinuclear potassium–cobalt–potassium complex

The synthesis and X-ray crystal structure of tetrakis[1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)-ethanato(1–)]dipotassiumcobalt(II), [Co(L2K)2], a novel neutral K–Co–K complex, is reported. The cobalt(II) ion is tetrahedrally co-ordinated by four carboxyl oxygens, one from each of four open-chain polyether hydroxy-acid anion ligands L–. The polyether ligands are held in the correct positions to co-ordinate two potassium ions, each potassium being co-ordinated by ten oxygen atoms. Four interligand hydrogen bonds from hydroxy groups to carboxy oxygens add further stability to the [Co(L2K)2] structure. Crystals are monoclinic, a= 17.052(4), b= 14.263(4), c= 26.226(6)A, β= 106.71(2)°, and Z= 4. R= 0.069 for 2 338 reflections.

Transition-metal complexes containing phosphorus ligands. Part XV. ortho-Metallation reactions involving some triphenyl phosphite derivatives of ruthenium and rhodium

The complexes [Ru(CO)(Cl)H(PPh3)3], [Ru(CO)H2(PPh3)3], [Ru(CO)3(PPh3)2], and [RuH2(PPh3)4] react with triphenyl phosphite in hydrocarbon solvents to yield triphenyl phosphite derivatives which subsequently undergo ortho-metallation. Products which have been isolated and/or characterised include the substituted species [Ru(CO)(Cl)H(PPh3)2{P(OPh)3}] and [Ru(CO)(Cl)H(PPh3){P(OPh)3}2], and the metallated derivatives [Ru(CO)(Cl){P(OPh)3}2(pc)], [Ru(CO)H(PPh3){P(OPh)3}(pc)], [Ru(CO)H{P(OPh)3}2(pc)], and [Ru{P-(OPh)3}2(pc)2][pc = P(OPh)2(OC6H4)]. Attempts to reverse the metallation process by addition of hydrogen chloride or hydrogen to [Ru{P(OPh)3}2(pc)2] under mild conditions have been usuccessful; however, this complex undergoes demetallation in the presence of perfluorocarboxylic acids, RFCO2H, to yield the species trans-[Ru(O2CRF)2{P(OPh)3}4]·RFCO2H (RF= CF3 or C2F5). The rhodium complex [RhH{P(OPh)3}4] in boiling n-heptance loses hydrogen to yield the metallated product [Rh{P(OPh)3}3(pc)].

Co-ordination of alkali metals by open-chain polyethers in transition metal complexes. Part 4. Variation in alkali-metal ion selectivity in cobalt and zinc complexes of 1-(o-carboxymethoxyphenoxy)-2-(o-hydroxyphenoxy)ethane (HL) and the X-ray and molecular structure of [Zn(NH4L2)2]

The syntheses of complexes of the title ligand [Zn(ML2)2](M = K, Rb, or NH4) are described. The X-ray structure of [Zn(NH4L2)2] is compared with those of [Co(ML2)2](M = K or Rb), and the importance of the hydrogen-bonded dimer L2 in the chemistry of HL is discussed. Subtle changes in M′ of [M′(ML2)2] give large changes in the selective binding of the alkali metal M. Crystals of [Zn(NH4L2)2]are orthorhombic, space group Pncb, with a= 14.046(7), b= 14.577(5), c= 16.691(11)A and Z= 2. The structure was refined to R= 0.071 for 1 595 reflections.

Transition-metal complexes containing phosphorus ligands. Part XIV. ortho-Metallation reactions involving some triaryl phosphite derivatives of osmium

Osmium triphenylphosphine complexes, [OsH4(PPh3)3], [OsH2(CO)(PPh3)3], and [OsHCl(CO)(PPh3)3] react with triphenyl phosphite in boiling organic solvents to yield triphenyl phosphite derivatives which subsequently undergo ortho-metallation. Products isolated and characterised include the substituted derivatives [OsHCl(CO)(PPh3)2(p)] and [OsHCl(CO)(PPh3)(p)2], the metallated species [OsCl(pc)(CO)(PPh3)(p)], [OsCl(pc)(CO)(p)2], [OsH(PC)(CO)(PPh3)(p)], and [OsH(pc)(CO)(p)2], and the dimetallated complexes [Os(pc)2(p)2] and [Os(pc)2(CO)(p)][(P)= P(OPh)3; (pc)=(PhO)2P(OC6H4)].