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Treatment of Z-PPh2CH2C(But)=NNH2 with 4-methylphenylthiomethyl methyl ketone gave the thioether azine phosphine Z,E-PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4) 1, which with H2O2 gave the corresponding phosphine oxide 2. Treatment of 1 with [Mo(CO)3(η6-cht)] or [W(CO)3(NCEt)3] gave the yellow tricarbonyl complexes fac-[M(CO)3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 3a (Mo) or 3b (W), respectively. Treatment of 1 with [Mo(CO)4(nbd)] gave the pale yellow tetracarbonylmolbdenum(0) complex [Mo(CO)4{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 4, in which the ligand 1 is bidentate through P and N. Oxidation of either 3a or 4 with 1 equivalent of bromine gave the orange neutral seven-coordinate dicarbonylmolybdenum(II) complex [MoBr2(CO)2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 5, whereas the tungsten complex 3b with 1 equivalent of bromine gave the seven-coordinate tricarbonyltungsten(II) cation [WBr(CO)3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]+ isolated as the PF6 salt 6. Treatment of 1 with [PtCl2(NCMe)2]gave the yellow dichloroplatinum(II) complex [PtCl2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 7, in which 1 is bidentate through P and N. When 7 was treated with NH4PF6 in methanol it gave the terdentate salt [PtCl{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]PF68a. Deprotonation of 7 with NEt3-NaOH gave the orange neutral chloroplatinum(II) complex [PtCl{PPh2-CH2C(But)N-NC(Me)=CHS(C6H4Me-4)}] 9, containing a terdentate ene-hydrazone phosphine ligand. This neutral complex 9 was reprotonated using HBF4 to give the BF4 salt 8b. Treatment of the phosphine 1 with [PtMe2(cod)] gave the white dimethylplatinum(II) complex [PtMe2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 10, containing the bidentate azine ligand. Treatment of 10 with MeI gave the white platinum(IV) iodide salt fac-[PtMe3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]I 11a in which the azine is terdentate. When 11a was treated with NH4PF6 in MeOH the PF6 salt 11b was obtained. Treatment of 10 with picric acid gave the yellow methylplatinum(II) picrate salt [PtMe{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}][OC6H2(NO2)3-2,4,6] 12 and methane. Infrared, 31P–[1H], 1H, and some 13C–[1H] NMRdata are given. Keywords: azine phosphine, thioether, metal-carbonyls, platinum.

Condensation of Z-PPh2CH2C(tBu)NNH2 with 2-halobenzaldehydes gave mixed azines of the type ZE-PPh2CH2C (tBu)NNCH(C6H4X-2) (X = I, 2a; Br, 2b; Cl, 2c; or F, 2e, respectively). 2a, 2b, or 2c reacted with fac-[W(CO)3(NCEt)3] to give tungsten(0) complexes [W(CO)3(NCEt){PPh2CH2C(tBu) NNCH(C6H4X-2)}] (3a–3c), which rapidly underwent oxidative addition to give seven-coordinate tungsten(II) complexes of the type [WX(CO)3{PPh2CH2C(tBu)NNCH(C6H4)}] (4a–4c). The fluoro- mixed azine Ph2PCH2C(tBu)NNCH(C6H4F-2) (2e) with fac-[W(CO)3(NCEt)3] gave [W (CO)3(NCEt){PPh2CH2C(tBu)NNCH(C6H4F-2)}] (3e) which did not undergo CF oxidative addition, but when treated with CO or CNtBu gave tungsten(0) complexes of the type [W(CO)3L{PPh2CH2C(tBu)NCH(C6H4F-2)}] (L = CO, 5a or CNtBu, 5b). The mixed azine from 2-chloro-6-fluorobenzaldehyde and 1 i.e. PPh2CH2C(tBu)NNCH(C6H3Cl-2,-F-6) (2d) with fac-[W(CO)3(NCEt)3] underwent oxidative addition at the CCl bond to give [WCl(CO)3{PPh2CH2C(tBu) NNCH(C6H3F-6)}] (4d) via a tungsten(0) complex 3d. Treatment of the aryl-tungsten(II) complex [WBr(CO)3{PPh2CH2C(tBu)NNCH(C6H4)}] (4b) with NaBH4/CO caused aryltungsten bond fission (reductive elimination) and CN reduction to give the benzylhydrazone-phosphine complex [W(CO)4{PPh2CH2 C(tBu)NNHCH2Ph}] (6) which was also formed by reducing the benzaldehyde mixed azine phosphine tungsten(0) complex [W(CO)4{PPh2CH2C(tBu)NNCHPh}] (8) with NaBH4.

Treatment of [Cr(CO) 4 (nbd)] (nbd  norbornadiene) with Z , Z -PPh 2 CH 2 C( t Bu)NNC( t Bu)CH 2 PPh 2 gave the title compound 2b , the structure of which was determined by a single crystal X-ray diffraction study. The proton NMR spectrum of 2b at 308 K and 400 MHz showed that for each of the methylene groups the protons are equivalent, but the spectrum is temperature dependent and at 188 K the slow exchange limiting spectrum is obtained, with all methylene hydrogens chemically non-equivalent; corresponding changes were observed in the 13 C-{ 1 H} NMR spectrum. The behaviour is due to the fluxionality of the 9-membered ring.

Treatment of the molybdenum tetracarbonyl complex of 3-diphenylphosphino-(1R)-(+)-camphor dimethylhydrazone [Mo(CO)4(PPh2C10H15NNMe2] (1a) with hydrogen chloride effects a rapid Redox/Fission reaction to give the molybdenum(II) imine complex [Mo(CO)3Cl2(PPh2C10H15NH)] (2a). Other strong acids HX reacted similarly to give analogous complexes [Mo(CO)3X2(PPh2C10H15NH)] (X = Br, I or OOCCF3). Reduction of 2a with sodium borohydride in the presence of carbon monoxide gave [Mo(CO)4(PPh2C10H15NH)] (1b), the crystal structure of which was determined. Treatment of 1b with LiN(SiMe3)2, followed by MeI gave [Mo(CO)4(PPh2C10H15NMe)] (1c). Treatment of 1a with bromine gave the tricarbonylmolybdenum(II) complex [Mo(CO)3Br2(PPh2C10H15NNMe2)] (2e). NMR and IR data, and bond length/bond angle data for 1b, are given.

Treatment of lithiated d-camphor with a half molar equivalent of PPh2Cl gives the 3-diphenylphosphino enolate anion [PPh2(C10H14O)]− as the only phosphorus-containing species. Treatment of lithiated d-camphor with one equivalent of PPh2Cl gives some of the enolate anion but the main product is the 3-exo substituted camphor derivative 3-exo-PPh2(C10H15O) together with some of the 3-endo-substituted derivative. On storage of the solution, the 3-endo substituted derivative becomes the main product with some of the 3-exo-substituted derivative still present. Treatment of a solution of the enolate ion with Na2PdCl4 · 4H2O gives or with PtCl2(cyclo-octa-1,5-diene), cis- is formed. Treatment of these bis-chelate complexes with hydrogen chloride opens up the chelate rings reversibly, giving dichloro-complexes of type [MCl2{(PPh2)C10H15O}2] {M = Pd (trans-isomer) M = Pt (cis-isomer)}. Treatment of ethanol or methanol solution of these bischelate complexes with acetylenes, especially in the presence of traces of acetic acid also opens up the chelate rings to give di-acetylides of type [M(CCR)2{(PPh2)C10H15O}2] {M = Pd or Pt; R = Ph or C(Me) = CH2}. When treated with HCCH or EtCCH the bis-chelate gives the corresponding acetylides but these could not be isolated and reverted to the starting bis-chelate complex, i.e. acetylide formation is reversible.

Treatment of cis -[PtCl 2 (PPh 2 CHCH 2 ) 2 ] with Me 2 NNH 2 in hot benzene gives the title compound ( 1a ) in high yield. Similar treatment of [PtX 2 (PPh 2 CHCH 2 ) 2 ], X  Br or I, gives the corresponding bromo- or iodo-complexes [XPt(NMe 2 NHCH 2 -CHPPh 2 CH 2 CH 2 PPh 2 )]X, X  Br or I. 1a with NH 4 PF 6 gives the corresponding PF 6 salt [ClPt(NMe 2 NHCH 2 CHPPh 2 CH 2 CH 2 PPh 2 )][PF 6 ], which with dilute HCl and NH 4 PF 6 gives [ClPt(NMe 2 NH 2 CH 2 CHPPh 2 CH 2 CH 2 PPh 2 )][PF 6 ] 2 . Treatment of 1a with NaBH 4 gives a neutral hydrido complex, formulated as [HPt(NMe 2 -NHCH 2 CPPh 2 CH 2 CH 2 PPh 2 )]. The crystal structure of 1a has been determined. NMR data are given.

Treatment of Ph 2 PCHCH 2 with [PtCl 2 (NCPh) 2 ] or with [PtCl 2 (COD)], gives cis -[PtCl 2 (PPh 2 CHCH 2 ) 2 ], which on treatment with LiBr gives the corresponding dibromide, or with NaI, the corresponding di-iodide. In dichloromethane solution, cis -[PtI 2 (PPh 2 CHCH 2 ) 2 ] partially isomerizes to give a cis/trans -mixture. Treatment of [PtMe 2 (COD)] with Ph 2 PCHCH 2 gives cis -[PtMe 2 (PPh 2 CHCH 2 ) 2 ]. Treatment of [PdCl 2 (NCPh) 2 ] with Ph 2 PCHCH 2 gives a mixture of cis - and trans -[PdCl 2 (PPh 2 CHCH 2 ) 2 ], which with LiBr gives a similar mixture of the corresponding dibromides, while reaction with NaI gives trans -[PdI 2 (PPh 2 -CHCH 2 ) 2 ]. 31 P 1 H NMR and 1 H- and 1 H 31 P NMR, and IR spectroscopic K64 data are given.

Le solvate allylamine du {N-[bis-(diphenylphosphino)-2,2 ethyl] allylamine-P,P} tricarbonyl(triphenylphosphine) W(O), [W(CO) 3 (C 18 H 5 P)(C 29 H 29 NP 2 )]•1/2C 3 H 7 N, cristalise dans P1 avec a=11,847, b=12,335 et c=17,402 A, α=87,70, β=86,86 et γ=73,28 o , Z=2; affinement jusqu'a R=0,0322. La coordination du coordinat vinylidene bis-diphenylphosphine (vdpp) a un atome W dans le complexe mer-[(OC) 3 W (vdpp) (PPh 3 ) active la double liaison C=C qui subit une addition de Michael avec l'allylamine (C 3 H 5 NH 2 ) pour donner mer-[(OC) 3 W{(Ph 2 P) 2 CHCH 2 N(H)C 3 H 5 }(PPh 3 )]

Some benzo-crown ethers, substituted in the arene ring, are described e.g. 15-X substituted benzo-15-crown-5 ether(1,X = CCPh, CHCHCOOH, CHCHCOOMe, CHCHCOOEt, CHCHCOCl). 15-Iodo-benzo-15-crown-5 and 18-iodo-benzo-18-crown-6, oxidatively add to Pd(PPh3)4 to give trans-[PdIR(PPh3)2], R=(2) or(3)). [Pt(stilbene)(PPh3)2] reacts similarly with the aryl iodides to give trans-[PtIR(PPh3)2](R=(2), (3), (4)-dimethoxy-phenyl. The platinum complexes with R = (2), (3) or (4) appear to form adducts with sodium iodide in solution. trans-[PtIR(PPh3)2] was converted to the corresponding thiocyanate and chloride (via the nitrate). PhCCR (R = (2) or 3,4-dimethoxyphenyl) react with cis-[PtCl2(PPh3)2 in the presence of hydrazine to give [Pt(PhCCR)(PPh3)2] and PhCCR react with [CO2(CO)8] to give [Co2(PhCCR))CO)6], with Ni(C5H5)2 to give [Ni2(C5H5)2(PhCCR)] and with W(CO)6 in acetonitrile to give [W(CO)(PhCCR)3]; PMe2Ph displaces the CO from [W(CO)(PhCCR)3] to give [W(PMe2Ph)(PhCCR)3]. [Cr(CO)6] reacts with the benzo-crown ethers RH, R = (2),(3) or (4) or with 1,2-dimethoxybenzene to give yellow arenechromium tricarbonyl complexes of the type [Cr(CO)3(RH)]. [Cr(CO)3(benzo-15-crown-5) forms a green 1 1 adduct with NaSCN.

Five complexes of type cis-[PtCl2(PR3)Q] (PR3 =PMe3, PMe2Ph, PEt3; Q = CH2 CHOCOCH3 or CH2=CHCH2OCOCH3) have been prepared. The crystal structure of cis-[PtCl2[PME2Ph)(CH2=CHOCOCH3)] is described. Crystals of cis-[PtCl2(PME2Ph)(CH2-CHOCOCH3)] are triclinic, with a 8.441(4), b 13.660(5), c 7.697(3) A, a 101.61(3)°, β 111.85(3)° γ 95.22(3)°, pP1, Z = 2. The structure was determined from 2011 reflections I σ 3σ (I) and refined to R = 0.037. The CH3COO grouping is syn to the cis-PMe2Ph ligand, with bond lengths of PtCl (trans to P) 2.367(3), PtCl (trans to olefin) 2.314(3), PtP 2.264(2), and PtC of 2.147(12) and 2.168(11) A. The complexes cis-[PtCl2- (PR3)Q] were studied by variable temperature 1H and 31P NMR spectroscopy. Spectra of the vinyl acetate complexes were temperature dependent as a result of rotation about the platinum—olefin bond. The rotation was “frozen out” at ca. 240 K; for cis-[PtCl2(PME2Ph)(CH2=CHOCOCH3] ΔG≠ (rotation) 15.0 ± 0.2 kcal mol-1. NMR parameters for the rotamers are reported. NMR studies of the interaction between chloro-bridged complexes of type [Pt2Cl2(PR3)2] (PR3 = P-N-Pr3 or PMe2Ph) and vinyl acetate shows that even at low temperatures (213 K) equilibrium favours the bridged complex and the proportion of trans-[PtCl2(PR3)CH2=CHOCOCH3)] is very small e.g. 2%. The allyl acetate complexes cis-[PtCl2(PR3)(CH2=CHCH2OCOCH3)] showed only one rotamer over the range 333–213 K. Reversible dissociation of cis-[PtCl2(PMe2Ph)- (CH2=CHCH2OCOCH3)] to [Pt2Cl4(PMe2Ph)2] + allyl acetate was studied at ambient temperature. At low temperatures e.g. 213–190 K addition of allyl acetate to a CDCl3 solution of [Pt2Cl2(P-n-Pr3)2] reversibly gave some olefin complex trans-[PtCl2(P-n-Pr3)(CH2=CHCH2OCOCH3)] and some O-bonded complex trans-[PtCl2(P-n-Pr3)(CH2=CHCH2OCOCH3)].

The complexes trans -[PdCl 2 L 2 ] {L = P-t-Bu (benzyl) 2 or P-t-Bu 2 (benzyl)} are shown to undergo internal metallation with difficulty to give complexes of the type [Pd 2 Cl 2 (PC) 2 ] {(P′C) = C 6 H 4 CH 2 P-t-Bu (benzyl) and (″C) = C 6 H 4 CH 2 P-t-Bu 2 }. The ligand P-t-Bu 2 (benzyl) undergoes metallation more readily than P-t-Bu(benzyl) 2 . The bridging chlorides of the binuclear complex [Pd 2 Cl 2 (P″C) 2 ] are replaced by bromide or iodide and the bridges may be split by various ligands to give mononuclear species.

Platinum(II) acetylides of the type trans-[Pt(CCR)2(PMe2Ph)2] (R = CH2OMe, CMe2OH, Ph) are reduced by hydrazine hydrate to dialkenylplatinum(II) complexes of the type trans-[Pt(CHCHR)2(PMe2Ph)2] in which the hydrogens are mutually cis on the alkenyl double bonds. Some of the complexes exist as rotational isomers in solution due to restricted rotation about the PtC single bonds. Mono-alkenyl complexes [PtCl(CHCHR)(PMe2Ph)2] (R = Ph or CMe2OH) were prepared by the hydrogen chloride fission of the dialkenyl complexes. trans-[PtCl(CClCHCH2OMe)(PMe2Ph)2] is formed when trans- [Pt(CCCH2OMe)2(PMe2Ph)2] is treated with hydrogen chloride whereas similar treatment of [Pt(CCCMe2OH)(PMe2Ph)2] gives [PtCl(CClCHCMeCH2)(PMe2Ph)2]. 1H, 13C and 31P NMR data are given and discussed.

C5H5FeC5H4CH2NMe2 reacts with sodium chloropalladate(II) in the presence of sodium acetate to give the internally metallated binuclear species [ Pd 2 X 2 {C 5 H 5 FeC 5 H 3 CH 2 N Me2}2] (X = Cl). The corresponding iodide was prepared as were mononuclear species [ Pd(acac) {C 5 H 5 FeC 5 H 3 CH 2 N Me2}] and [ Pd-{C 5 H 5 FeC 5 H 3 CH 2 N Me2}L] L = PMe2Ph, AsMe2Ph, P(OMe)3 or PPh3. 1H NMR data are given.

The syntheses and structures of trans-[RhCl(CO){t-Bu2(CH2)4CC(CH2)P4P-t-Bu2}] and [RhCl{t-Bu2 PCH2CH2CHCHCH2 CH2P-t-Bu2}] are reported.

An example of anchimeric assistance in an oxidative addition reaction is discussed. Stable large ring (12- to 45-membered) complexes have been prepared from diphosphines t-Bu2P(CH2)nP-t-Bu2 (n = 9, 10 or 12). Some unusual iridium chemistry, including an iridium(II) compound, has been generated from ligands such as di-t-butyl-2-methoxyphenylphosphine.

The cyclometallated monohydrides (R  H or Me) react with NaOPr i /Pr i OH/H 2 to give fluxional tetrahydrides, probably . These are highly fluxional having magnetically equivalent hydridic hydrogens, even at ---100°C. When treated with HBr, , gives and with CO it gives a mixture of complexes which are probably (2 isomers) and . When treated with Bu t NC this tetrahydride undergoes similar reactions but another (major) product is formed which appears to be binuclear and fluxional and is probably of type , with four bridging hydrogens.

The new phosphine, PBut2Bui (L), was prepared from But2PCl and LiBui. PPh2Bui (L′) was prepared from Ph2PCl and LiBui. Treatment of [PtCl2(NCBut)2] with L′ gives [PtCl2L′2] which does not cyclometallate even on prolonged boiling in 2-methoxyethanol. In contrast, [PtCl2(NCBut)2] reacts with PBut2Bui in boiling 2-methoxyethanol to give the cyclometallated complex [ Pt 2 Cl 2 (PBu t 2 CH 2 -CHMeCH 2)2] (II, X = Cl). The corresponding bromide, iodide and acetylacetonate were prepared. With PPh3 II (X = Cl) gives [ PtCl(PBu t 2 CH 2 CHMeCH 2)(PPh3)] which with NaBH4 gives [ PtH(PBu t 2 CH 2 CHMeC H2)(PPh3)]. Na2PdCl4 with L (2 mol equivalents) gave trans-[PdCl2L2], which was converted into trans-[Pd(NCS)2-L2] by metathesis with KSCN. Treatment of Na2PdCl4 with L (1 mol equivalent) gave [Pd2Cl4L2], which on heating in 2-methoxyethanol gave [ Pd 2 Cl 2 (PBu t 2 CH 2 -CHMeCH 2)2], as a mixture of syn- and anti-isomers. The complexes trans-[PdCl2-L′2] and [Pd2Cl4L′2] were also prepared. 1H- and 31P NMR data are given.

Several new platinum(II) acetylide complexes, trans-{Pt[CCCR1R2(OR3)]2-L2} (R1, R2  H, Me, Et; CR1R2  cyclohexylidene; R3  H, Me or Ph), trans-[Pt(CCCH2CH2OH)2L2], trans-[Pt(p-tolylacetylide)2L2] and trans-[PtX(p-tolylacetylide)L2] (L  PMe2Ph or in one case, AsMe2Ph) have been prepared. Platinum(II) acetylide complexes with tertiary hydroxyl groups are easily dehydrated by acetic anhydride/pyridine to give platinum-enyne complexes. Analogous compounds with primary hydroxyl groups do not dehydrate but give acetates. 1H and 13C NMR data are given and the shift reagent Eu(fod)3 was used to analyse the 1H NMR spectrum of trans-[Pt(CCCH2CH2OH)2(PMe2Ph)2].

Treatment of [PtCl2(NCBut)2] or [PtCl2(cyclo-1,5-octadiene)] with Ph2P(CH2)n P(O)Ph2 (n = 1, dppmO; n = 2, dppeO; n = 3, dpppO; n = 4, dppbO) gives complexes of the type cis-[PtCl2{Ph2P(CH2)nP(O)Ph2}2], independently of mole ratio. Treatment of cis-[PtCl2(dppmO)2] with LiBr or NaI gives [PtX2(dppmO)2] (X = Br, cis; X = I, cis/trans mixture) and on treatment with Hg(CCPh)2 in ethanol, trans-[Pt(CCPh)2(dppmO)2] is formed. Treatment of these ligands with [PtMe2(cyclo-octa-1,5-diene)] gives exclusively cis-[PtMe2{Ph2P(CH2)nP(O)Ph2}2]. Coordination of the PO group was achieved by treating [PtCl2{Ph2P(CH2)nP(O)Ph2}2] with either AgNO3 or TlPF6, whereupon cis-[Pt{Ph2P(CH2)nP(O)Ph2-P,O}2]2+ (n = 1, or 2) is formed: these cations were also synthesized by treating [PtMe2{Ph2P(CH2)nP(≈O)Ph2}2] with HBF4. Treatment of [PdCl2(NCPh)2] with dppmO gives trans-[PdCl2(dppmO)2] only and this reacts with AgNO3 or TlPF6 to form cis-[Pd(dppmO-P,O)2]2+. The complexes were characterized by microanalysis, IR and NMR spectroscopy.

Treatment of [PtCl 2 (dppm- PP ′)] (dppm = Ph 2 PCH 2 PPh 2 ) with NaCCH and dppm in liquid ammonia gave [Pt(CCH) 2 (dppm- P ) 2 ] ( 1 ). This complex is fluxional at 20°C due to rapid ‘end over end’ motion of the dppm ligands. Treatment of 1 with various metal complexes gave heterobimetallics, usually in good yield. Thus with [Ag 4 Cl 4 (PPh 3 ) 4 ] it gave [(HCC) 2 Pt(μ-dppm) 2 AgCl]; with [AuCl(PPh 3 )], [(HCC) 2 pt(μ-dppm) 2 Au]Cl; with [Rh 2 Cl 2 (CO) 4 ], [(HCC) 2 Pt(μ-dppm) 2 Rh(CO)]Cl; with [IrCl(CO)(PPh 3 ) 2 ], [(HCC) 2 Pt(μ-dppm) 2 IrCl(CO)]; and with [W(CO) 3 (NCMe) 3 ], it gave [(HCC) 2 Pt(μ-dppm) 2 W(CO) 3 ]. IR, 31 P{ 1 H} NMR and 1 H NMR data are given.

Treatment of complexes of the type [M(CO) 4 {(Ph 2 P) 2 CCH 2 }] (M = W, Mo or Cr) with functionalized lithium reagents, LiR, followed by hydrolysis gives complexes of the type [M(CO) 4 {PH 2 P) 2 CHCH 2 R}] in high yields; R = C 6 H 4 Me-4, C 6 H 4 OMe-2, C 6 H 3 (OMe) 2 -2,6, C 6 H 4 OH-2, C 6 H 4 (COOH)-2, CH 2 COPh or CH 2 COMe. IR, and 31 P and 1 H NMR data are given.

The trans-PH2PCH=CHPPh2 (t-dppe)-bridged bimetallic 10-membered ring complexes [M2(CO)8(μ-t0dppe)2] (M = Cr or MO) have been synthesized by treatment of the metal hexacarbonyl with one equivalent of t-dppe at elevated temperature. the fluxional process in the Mo(μ-t-dppe) Mo ring has been studied by variable temperature 13P-{1H} NMR spectroscopy and is characterised by a change from an A4 spin system at +20°C to an AA′BB′ system at −100°C. The bimetallic complex [Mo2(CO)6(μ-tdppe)3] has been prepared and 13P-{1H} NMR studies indicate that in solution all four phosphorus nuclei are equivalent, even at −115°C. Attempts to prepare related heterobimetallic complexes are also described. Crystals of [Mo2(CO)8(μ-trans-Ph2PCH=CHPPh2)2] are monoclinic, space group P21/a, with a 2020.2(5), b 1423.1(5), c 2145.1(5) pm, β 113.95(2)°, and Z = 4; final R factor 0.0465 for 5668 observed reflections. The structure shows two [Mo(CO)4] moieties linked by two trans-dppe bridges to give a 10-membered Mo2P4C4 ring.

Complexes of type [M(CO) 4 PPh 2 CH 2 PPh 2 )], when treated succesively with LiBu n and Ph 2 PCl give complexes of type [M(CO) 4 {(Ph 2 P) 3 CH}] i.e. [M(CO) 4 (tripod)], in which the triphosphine is bidentate. These may be oxidized (H 2 O 2 ) to the corresponding phosphine oxide [M(CO) 4 {(Ph 2 P) 2 CHP(O)Ph 2 }] or converted with sulphur to the corresponding phosphine sulphide. The complexes of type [M(CO) 4 {(PPh 2 ) 3 CH}] (L) react with K 2 PtCl 4 to give what are probably complexes of type PtCl 2 L 2 , or with bridge complexes of type [Pt 2 Cl 4 Q 2 ] (Q = PPr n 3 or PMe 2 Ph) to give heterobimetallic complexes of type trans -[PtCl 2 QL]. IR and NMR data are given and discussed.

The preparation and properties of a new series of carboxylato-bridged binuclear π-allyl and π-2-methylallyl complexes of palladium(II) are described. Nuclear magnetic resonance data are given.

The substitution of Group VI metal carbonyls by tertiary phosphines, triphenylarsine or dipyridyl is greatly accelerated by a two-phase system, benzene/ 50% aqueous sodium hydroxide, in the presence of tetra-n-butylammonium iodide as phase-transfer catalyst.

The preparation of dihapto {8-methylene)-1-naphthyl}bis(triphenyl-phosphine)platinum(II), involving an internal metallation reaction, is described.

The bulky teratiary phosphines P-t-Bu2Ph and P-t-Bu2-p-tol, provide binuclear ruthenium(I) complexes. An X-ray analysis of [Ru2Cl2(CO)4(P-t-Bu2-p-tol)2] shows the RuCl2Ru bridge to be non-planar and to have an RuRu distance of 2.632A.

One of the sets of hydride 1 H NMR patterns for the isothiocyanato/thiocyanato mixture trans - [PtH(SCN) (PEt 3 ) 2 ] is broad. Previously there had been disagreement on the cause of this broadening. It is now shown to be due to the 14 N quadrupole by double resonance.