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The first organotin(IV), aluminium(III)-μ-oxoisoprovides of the type [R3SnOA](OiPr)2] (R = Me or Ph) have been made by heating of trimethyl- or triphenyl-tin acetate with aluminium isopropoxide. The reactions of these μ-oxoisopropoxides with benzoylacetone in 1:1 and 1:2 molar ratios yielded the compounds of the type [R3SnOAl(OiPr)(bzac)] and [R3SnOAl(bzac)2] (where R = Me or Ph and bzac = deprotonated benzoylacetone), respectively.

The yellow complex trans-[PtCl2L2] (L = PPh2CH(SiMe3)2) has been characterised. An attempt to make a similar complex with the more sterically hindered phosphine PPh2C(SiMe3)3 resulted in the loss of a trimethylsilyl group from one phosphine ligand and activation of a CH bond in another to give the white complex PtClPPh2C(SiMe3)2SiMe2CH2{PPh2CH(SiMe3)2}, the structure of which was established by X-ray diffraction.

The synthesis of the trans -spanning bidentate diphosphine ligand, 3,3′-oxybis-(di- meta -tolylphosphino)methyl]benzene (I) and its complexes with Ni II , Pd II and Pt II are described. The ligand I forms monomeric trans square planar complexes [MX 2 (I)] (M = Ni, Pd or Pt, X = Cl or X = NCS in case of Ni). 31 P and 1 H NMR parameters are reported.

The bidentate ditertiaryphosphine ligand, bis{3-[bis(3-trifluoromethylphenyl) phosphinomethyl]phenyl} ether (LL) forms monomeric trans-square planar complexes [MX2(LL)] (M = Ni, Pd or Pt, X = Cl; M = Ni, X = NCS) as well as trans-[PtHCl(LL)]; 31P and 1H NMR, and selected IR parameters are reported.

Reaction of dimethyldiacetoxysilane with aluminium isopropoxide was carried out in 1 : 2 molar ratio in refluxing cyclohexane and a mixed [Si(IV), Al(III)] μ-oxo-isopropoxide of the composition Me 2 SiO 2 Al 2 (OPr i ) 4 was isolated. This compound was characterised by elemental analysis and IR and NMR spectral studies. The tertiary butanol derivative, Me 2 SiO 2 Al 2 (OBu t ) 4 , was prepared by alcoholysis. Reactions of this mixed [Si(IV), Al(III)] μ-oxo-isopropoxide with monobasic bidentate carboxylic acids, such as trans -cinnamic acid (HCA) and dihydrocinnamic acid (HDCA) and with dibasic tridentate carboxylic acids such as salicylic acid (H 2 SA) and benzilic acid (H 2 BA) were also studied. Products of the type Me 2 SiO 2 Al 2 (OPr i ) 4- n (L) n [where HL = trans -cinnamic acid (HCA), dihydrocinnamic acid (HDCA) and n = 1,2,3 or 4] and Me 2 SiO 2 Al 2 (OPr i ) 4-2 n (L) n [where H 2 L = salicylic acid (H 2 SA), benzilic acid (H 2 BA) and n = 1 or 2] were isolated and characterised by elemental and spectral studies.

Complexes of the type [XMo(CO) 2 (η 3 -C 3 H 5 )(PP′)] (X  Cl or Br; PP′  R 2 PCH 2 CH 2 PPh 2 ; R = m -FC 6 H 4 ( 1a ), p -FC 6 H 4 ( 1b ), m -CF 3 C 6 H 4 ( 1c )) have been prepared from the reaction of [XMo(CO) 2 (η 3 -C 3 H 5 )(MeCN) 2 ] with the relevant ditertiary phosphines in acetone. From their 1 H NMR and IR data these complexes have been assigned essentially octahedral structures in which the allyl moiety is trans to be unidentate anion, and the two cis -carbonyl groups and two phosphorus donor atoms of the bidentate ligand are approximately coplanar. CO force constants have been calculated.

Iodobenzene adds to the palladium(0) complex Pd(VP)2 (2) (VP = (2-vinylphenyl)diphenylphosphine, o-CH2CHC6H4PPh2) to give the planar palladium(II) complex PdI{o-CH(CH3)C6H4PPh2}{(E)-o-Ph2PC6H4CHCHC6H5} (5), which has been characterized by NMR (1H, 31P) spectroscopy and by single crystal X-ray analysis. Crystals of 5 are triclinic, space group P 1 , a 13.404(5); b 13.850(6), c 14.158(7) A, α 118.39(3), β 92.28(4), γ 95.58(3)°, Z 2; 2139 data with I > 2σ(I) were refined to R 0.087, Rw 0.049. The complex contains a five-membered chelate σ-alkyl group (PdP(1) 2.279(6), PdC(1) 2.05(3) A) and monodentate P-bonded E-(2-styrylphenyl)diphenylphosphine (PdP(2), 2.346(7) A). 5 is believed to be formed by a sequence of oxidative addition, phenyl migration from palladium to one of the vinyl groups, and β-hydride transfer from one P-donor ligand to the other. Bromobenzene reacts with 2 to give the bromo analogue of 5 together with an unidentified minor isomer. Allyl bromide gives PdBr(η3-C3H5)(VP) containing monodentate P-bonded VP, but the products of reaction of 2 with methyl iodide and benzyl bromide have not been fully characterized.

Lanthanide chlorides form adducts of the type [Ln(L)nCl3] (where Ln = La, Pr, Nd, Sm, Eu, when n = 6; and Ln = Gd, Tb, Dy or Yb when n = 5; and L = (EtO)2P(O)H or (PriO)2P(O)H upon interacting with the diethyl and diisopropyl phosphites in dry ethyl and isopropyl alcohol, respectively. Complexes were recrystallised from ethanol or isopropanol and washed with n-hexane. On the basis of elemental analysis, infrared, 1H NMR and 31P NMR spectral studies, it is concluded that these phosphites coordinate to the lanthanide metal atom through the oxygen atom which has the greatest affinity for lanthanides in these adducts.

The first phenylmagnesium carboxylates, C6H5MgOOCR·THF, have been made by reaction of phenylmagnesium bromide with the sodium salt of carboxylic acids [RCOONa {where R = CH3, ClCH2, Cl2CH, Cl3C, CH3CH2, (CH3)2CH, C6H5CH2 and CH3(CH2)3CH2}]. All these derivatives are white or pale yellow solids, soluble in polar solvents. The carboxylates have been characterized by elemental analysis, conductance measurements, and spectral studies (1H NMR and IR). The IR data suggest that carboxylate group acts as a bridging bidentate ligand.

The ditertiary phosphines, 1-diphenylphosphino-2-bis( m -fluorophenyl) phosphinoethane ( 1a ), 1-diphenylphosphino-2-bis( p -fluorophenyl) phosphinoethane ( 1b ), 1-diphenylphosphino-2-bis( m -trifluoromethylphenyl) phosphinoethane ( 1c ) complexes of ruthenium(II) of the type [Ru(PP′) 2 X 2 ] (X = Cl, Br, I, NCS, PP′ = 1a , 1b or 1c ) and [Ru(CO) 2 (PP′)X 2 ] (X = Cl, Br, I) have been prepared and characterized on the basis of elemental analysis, IR, UV, 1 H NMR and 31 P NMR (in a few cases) data. Based on the result of these studies, trans - and cis -octahedral structures for [Ru(PP′) 2 X 2 ] and [Ru(CO) 2 (PP′)X 2 ] complexes, respectively, have been proposed. In all these cases, the ditertiary phosphines act as potential bidentate chelating ligands.

Complexes [MX2(1)] (M = Ni, Pd and Pt; X=Cl and NCS; 1 = 2,11-bis(dialkyl-[or diaryl]phosphinomethyl)benzo[c]phenanthrene; alkyl = cyclohexyl t-butyl; aryl = m-tolyl, p-anisyl and m-CF3 C6H4) have been synthesized. An NMR. study of the t-butyl complexes provides evidence for a “fan-like” motion of the benzo[c]phenanthrene moiety over the plane of the complex.

The preparation of the ditertiary phosphines 2,11-bis (di-m-tolylphosphinomethyl)benzo [c]phenanthrene (1b), 2,11-bis (di-p-anisylphosphinomethyl)benzo-[c]phenanthrene (1c), 2,11-bis (di-m-trifluoromethylphenylphosphinomethyl) benzo-[c]phenanthrene (1d), 2,11-bis (dicyclohexylphosphinomethyl)benzo [c]phenanthrene (1e) and 2,11-bis [di-(t-butyl)phosphinomethyl]benzo [c]phenanthrene (1f), by a combination of synthetic routes is described.

New complexes of the type [M(CO) 4 (dptpe)] (M = Cr, Mo, W) have been isolated from the reaction of the ligand, 1, 2-bis(di- p -tolylphosphino)ethane (dptpe) with Group VI metal hexacarbonyls in a suitable solvent such as methylcyclohexane. The resulting [M(CO) 4 (dptpe)] complexes on treatment with an excess of pyridine produces the mixed ligand complexes [M(CO) 3 (py)(dptpe)], whereas the reaction of [XMo(CO) 2 (η 3 -allyl)(MeCN 2 )] (X = Cl, Br) with dptpe gives [XMo(CO) 2 (η 3 -allyl)(dptpe)]. The formulation of the structures of these complexes follows from elemental analyses and 1 H NMR, 31 P{ 1 H} NMR and IR spectral studies. Carbonyl force constants have been calculated from the ν(CO) stretching frequencies by the Cotton and Kraihanzel method.

Compounds of the type [M(OPri]m-n(L)n] (where m=3 and n=1 to 3, M=La, Sm, Nd or Gd and L=C7H5O3 −, C9H7O2 − and C9H9O2 −) have been synthesised by the reactions of lanthanide isopropoxides with furylacrylic acid (C7H5O3), cinnamic acid (C9H8O2) and dihydro cinnamic acid (C9H10O2) in benzene. All compounds have been characterised by elemental analysis, and infrared spectral studies. On the basis of infrared studies it is suggested that all these acids behave as a bidentate chelate of the type

The reaction of PtCl2L (L = diphosphine) with the appropriate diphosphine L′ in ethanol followed by reduction with aqueous sodium borohydride leads to either disproportionation to give mixtures of the bis(diphosphine) complexes PtL2 and PtL′2 or to the formation of the mixed ligand complex PtLL′ depending on the diphosphines. Mixed ligand complexes are obtained when L=Ph2P(CH2)2PPh2, L′ = Ph2P(CH2PPh2 cis-Ph2PCH CHPPh2, Ph2P(CH2)2AsPh2, Ph2- P(CH2)4PPh2, o-Ph2PC6H4PPh2; and L=(C6H11)2P(CH22P(C6H11)2, L′= Ph2P(CH2)PPh2, Ph2P(CH2)2PPh2 cis-Ph2PCHCHPPh2, (2S,3S)-Ph2PCH- (CH3)CH(CH3)PPh2, (R)-Ph2PCH(CH3)CH2PPh2. When L=Ph2P(CH2)4PPh2 L′= Ph2P(CH23PPh2 or cis-Ph2PCHCHRPh2 the mixed ligand complexes are obtained but extensive disproportionation also occurs.

Complexes of the type [M(CO)4(PP′)] (M = Cr, Mo, W; PP′ = R2PCH2CH2PPh2, R = m-FC6H4(1a), R = p-FC6H4 (1b), R = m-CF3C6H4 (1c)) have been obtained from the reaction of appropriate metal hexacarbonyl with the corresponding ditertiary phosphine in methylcyclohexane/xylene. The order of ease of replacement of carbonyl by these phosphines was found in the sequence of Mo > Cr > W. The complexes [M(CO)4(PP′)] react with excess of pyridine to yield the trisubstituted complexes [M(CO)3(py)(PP′)] (M = Cr, Mo, W; py = pyridine; PP′ = 1a, 1b or 1c). All the complexes have been characterized by elemental analysis and IR and 1H NMR spectroscopy, and are assigned octahedral structures. Carbonyl force constants have been calculated from the (ν)(CO) stretching frequencies. 31P{1H}NMR spectra of [M(CO)4(PP′)] complexes reveal unusually large downfield shifts upon coordination, and these are explained in terms of a ring contribution. The values of the tungsten-phosphorus J(183W-31P) and phosphorusphosphorus J(31P31P′) coupling constants are discussed.

The new chelating ditertiary phosphine (pptpf) forms low spin, diamagnetic, square-planar complexes of the type [M(pptpf)X2] (where M=Ni(II), Pd(II) or Pt(II); X=Cl, Br, I or NCS) when treated with corresponding metal salts. Group VI metal hexacarbonyls also react with the ligand (pptpf) to yield diamagnetic, octahedral complexes of type [M(CO)4(pptpf)] (where M=Cr, Mo or W). These complexes have been characterised on the basis of their elemental analysis, 1H n.m.r., electronic, infrared spectral measurements, electrical conductance and magnetic susceptibilities data. In all the complexes the ligand (pptpf) acts as a chelating ditertiary phosphine.

The ditertiary phosphines; [2-{di(p-tolyl)phosphino}ethyl] diphenylphosphine (pptpf) and [2-{di(m-tolyl}ethyl] diphenylphosphine (pmtpf) complexes of ruthenium of the type: [Ru(pptpf)2X2] [Ru(pmtpf)2X2] (where X = Cl,Br, I or NCS), [Ru(CO)2X2(pptpf)] and [Ru(CO)2X2(pmtpf)] (where X = Cl, Br, or I) were prepared. trans-octahedral structure for [Ru(pptpf)2X2] and [Ru(pmtpf)2X2] complexes and cis-octahedral structure for [Ru(CO)2X2(pptpf)] and [Ru(CO)2X2(pmtpf)] complexes on the basis of IR and proton NMR data have been suggested. In all these complexes ligands (pptpf) and (pmtpf) act as chelating ditertiary phosphines.

Reactions of niobium and tantalum pentaethoxides with ethyl-1-hydroxycyclohexylacetate (HECA), ethyl 2-hydroxy-2-arylpropionate (HEAP) and ethyl 2-hydroxy-2-aryl butyrate (HEAB) lead to compounds of the type [M(OEt)5−n(L)n] (where M=Nb or Ta; n=1, 2 or 3; and L=HECA, HEAP or HEAB). These were characterised by elemental analysis, molecular weight determinations and i.r. and n.m.r. spectral studies. Alcoholysis reactions witht-butanol were also carried out.

Lanthanide chlorides form six-coordinate octahedral adducts of the type [LnCl 3 (R 2 P(O)H) 3 ] (where Ln = La, Pf, Nd, Sm, Eu, Gd, Tb, Dy or Yb and R = C 6 H 11 , p -CH 3 C 6 H 4 , p - or m -CF 3 C 6 H 4 ) when interacted with diaryl and dicyclohexyl phosphine oxides in dry ethanol. Complexes were re-crystallised from n-hexane and on the basis of elemental analysis, infrared, and 31 p NMR spectral studies, it is concluded that these phosphine oxides coordinate to the lanthanide metal atom through the oxygen atom which shows the greatest affinity for lanthanides in these adducts.

Several reactions of rhodium(I) complexes of 1,2,5,6,8-pentamethylenecyclodecane (allene pentamer, C 15 H 20 ) are described. Reaction of the chloride C 15 H 20 RhCl with (pentafluorophenyl)lithium in diethyl ether gives the yellow crystalline σ-pentafluorophenyl derivative C 15 H 20 RhC 6 F 5 , apparently the first known example of a derivative with a transition metalcarbon σ-bond where all of the other ligands are coordinated carboncarbon double bonds. Reaction of C 15 H 20 RhCl with sodium cyclopentadienide in tetrahydrofuran solution gives yellow waxy C 15 H 20 RhC 5 H 5 shown by its NMR spectrum to have a tetrahapto -1,2,5,6,8-pentamethylenecyclodecane ligand and a pentahapto -cyclopentadienyl ligand. The predominant ion in the mass spectrum of C 15 H 20 RhC 5 H 5 is C 15 H 20 Rh + which is formed by loss of C 5 H 5 from the molecular ion. Reaction of C 15 H 20 RhCl with stannous chloride in diethyl ether gives yellow C 15 H 20 RhSnCl 3 . Reaction of C 15 H 20 RhCl with silver hexafluorophosphate in acetone solution gives the yellow salt [C 15 H 20 Rh][PF 6 ]. This salt reacts with carbon monoxide at atmospheric pressure to give the yellow monocarbonyl [C 15 H 20 RhCO][PF 6 ], which can also be obtained by reaction of C 15 H 20 RhCl with carbon monoxide in boiling ethanol followed by reaction with ammonium hexafuorophosphate in aqueous acetone.

The following metal complexes of the phosphine-diarsine [(C 6 H 5 ) 2 AsCH 2 CH 2 ] 2 PC 6 H 5 (abbreviated as AsfPfAsf) can be prepared by procedures analogous to the preparation of the corresponding complexes of the the triphosphine [(C 6 H 5 ) 2 PCH 2 CH 2 ] 2 PC 6 H 5 : ( 1 ) Monoligate monometallic (AsfPfAsf)Fe(CO) (COCH 3 )(C 5 H 5 ); ( 2 ) Biligate monometallic (AsfPfAsf)M(CO) 4 (M = Cr and Mo) and [C 5 H 5 Mo(CO) 2 (AsfPfAsf)][PF 6 ]; ( 3 ) Triligate monometallic [(AsfPfAsf)MCl][PF 6 ] (M = Pd and Pt), (AsfPfAsf)RhCl 3 , (AsfPfAsf)M(CO) 3 (M = Cr and Mo), and (AsfPfAsf)Mn(CO) 2 Br. Reaction of rhenium(III) chloride with AsfPfAsf in boiling acetonitrile gives brown (AsfPfAsf) 2 Re 3 Cl 9 . Reaction of osmium tetroxide and hydrochloric acid with AsfPfAsf in boiling ethanol gives the yellow-orange osmium(III) derivative (AsfPfAsf)OsCl 3 . Reaction of [Rh(CO) 2 Cl] 2 with AsfPfAsf in boiling toluene gives brown sparingly soluble (AsfPfAsf)Rh 2 (CO) 3 Cl 2 . Reaction of CH 3 Mo(CO) 3 C 5 H 5 with AsfPfAsf in acetonitrile at room temperature gives yellow monoligate monometallic (AsfPfAsf)Mo(CO) 2 (COCH 3 )(C 5 H 5 ) rather than a triligate trimetallic derivative. Similarly the reaction of CH 3 Mo(CO) 3 C 5 H 5 with the phosphine-arsine (C 6 H 5 ) 2 AsCH 2 CH 2 P(C 6 H 5 ) 2 (abbreviated as AsfPf) gives the yellow monometallic derivative (AsfPf)Mo(CO) 2 (COCH 3 (C 5 H 5 ) rather than a biligate bimetallic derivative.

A new bimetallic-μ-oxoisopropoxide [MgO2Al2(OPri)4] has been synthesized by thermal condensation of magnesium acetate (1 mol) and aluminium isopropoxide (2 mol) in refluxing decalin. The isopropoxy substitution reaction of this bimetallic [Al(III), Mg(II)]-μ-oxoisopropoxide with various β-diketones in molar ratios 1 : 1, 1 : 2 and 1 : 3 yielded compounds of the type [MgO2Al2(OPri)3(L)], [MgO2Al2(OPri)2(L)2] and [MgO2Al2(OPri)(L)3], respectively; where HL = HAcAc (acetyl acetone), HBzAc (benzoyl acetone) and HThTFA(2-thenoyl trifluoroacetone). The μ-oxo compound and its derivatives were characterized on the basis of elemental analysis, IR, 1H NMR 27Al NMR and molecular weight measurements.

In earlier publications1,2 we have reported the syntheses of halide and pseudohalide complexes of Ni(II), Pd(II) and Pt(II) containing the novel ditertiary phosphines(m- or p-CH3C6H4)2P[sbnd]CH2-CH2-PPh2. The complexes have shown to have greater solubilities in organic solvents compared with the well known ditertiary phosphine Ph2PdlCH2-CH2PPh2. In this paper we wish to report the syntheses of analogous complexes of the two ditertiary phophines with Ni(II), Pd(II) and Pt(II) and which contain vicinal M[sbnd]SH bonds. Recently monotertiary and ditertiary phosphine complexes of Ni(II), Pd(II) and Pt(II) containing vicinal M[sbnd]SH and M[sbnd]SeH groups have been reported.3–6 In spite of the vicinal groups, the complexes have been shown to exhibit remarkable stability towards air and moisture.

The ditertiary phosphines, 1-diphenylphosphino-2-bis( m -fluorophenyl) phosphinoethane ( 1a ), 1-diphenylphosphino-2-bis( p -fluorophenyl) phosphinoethane ( 1b ), 1-diphenylphosphino-2-bis( m -trifluoromethylphenyl) phosphinoethane ( 1c ) complexes of ruthenium(II) of the type [Ru(PP′) 2 X 2 ] (X = Cl, Br, I, NCS, PP′ = 1a , 1b or 1c ) and [Ru(CO) 2 (PP′)X 2 ] (X = Cl, Br, I) have been prepared and characterized on the basis of elemental analysis, IR, UV, 1 H NMR and 31 P NMR (in a few cases) data. Based on the result of these studies, trans - and cis -octahedral structures for [Ru(PP′) 2 X 2 ] and [Ru(CO) 2 (PP′)X 2 ] complexes, respectively, have been proposed. In all these cases, the ditertiary phosphines act as potential bidentate chelating ligands.

Reaction of the sodium carboxylates (I) with the Grignard reagent (II) in THF (III) leads to the formation of the new phenylmagnesium carboxylates (IV).

Lanthanide chlorides form six coordinate octahedral adducts of the type [Mcl 3 (R 2 P(0)H) 3 ] (where Ln = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy or Yb and R=C 6 H 11 -, p-CH 3 C 6 H 4 -. p or m-CF 3 C 6 H 4 ) when interacted with diaryl and cyclohexyl phosphineoxides in dry ethanol. Complexes were recrystallised from n-hexane and on the basis of elemental analysis, infrared and 31 P n.m.r. spectral studies it is concluded that the diaryl phosphineoxides coordinate to the lanthanide metal atom through the oxygen atom which shows the greatest affinity for lanthanides in these adducts. Efforts are on to test the applicability of these complexes in various fields such as n.m.r. shift reagents and in biological systems as structural probes.

The preparation of the ditertiary phosphines 2,11-bis (di-m-tolylphosphinomethyl)benzo [c]phenanthrene (1b), 2,11-bis (di-p-anisylphosphinomethyl)benzo-[c]phenanthrene (1c), 2,11-bis (di-m-trifluoromethylphenylphosphinomethyl) benzo-[c]phenanthrene (1d), 2,11-bis (dicyclohexylphosphinomethyl)benzo [c]phenanthrene (1e) and 2,11-bis [di-(t-butyl)phosphinomethyl]benzo [c]phenanthrene (1f), by a combination of synthetic routes is described.

The 1 : 1 complexes of chelating diphosphine, [2-{di(m-tolyl)phosphino}ethyl]diphenylphosphine (pmtpf), with nickel(II), palladium(II) and platinum(II) halides and thiocyanates and 2 : 1 complexes with nickel(II) perchlorates have been prepared. Ligand (pmtpf) forms low-spin square-planar and diamagnetic [M(pmtpf)X2](where X = Cl, Br, I or NCS; M = Ni, Pd or Pt) and [Ni(pmtpf)2]- (ClO4)2 complexes. Complexes of metal carbonyls having the general formula [(pmtpf)M(CO)4] (where M = Cr, Mo or W) have also been synthesized. These complexes have been characterized on the basis of element analysis, electronic, infrared and 1H N.M.R. spectral measurements, magnetic susceptibilities and electrical conductance data. In all cases studied this ligand acts as a chelating ditertiary phosphine.