Dichlorobis complexes

The only prominent antitumor tetravalent platinum complex so far is iproplatin (102). In vitro it has been shown to cause interstrand DNA-breaking and cross linking. Free radical scavengers inhibit these effects. The complex is less neurotoxic and less nephrotoxic than cisplatin. Its synthesis begins with hydrogen peroxide oxidation of cis-dichlorobis(isopropvlamine) platinum (100) to the dimethylacetamide complex 101. The latter is heated in vacuum to liberate iproplatin [25]. 

Dimethyl-I,l -biphenyl has been prepared by a wide variety of procedures, but few of these are of any practical synthetic utility Classical radical biarjl syntheses such as the Gomberg reaction or the thermal decomposition of diaroyl peroxides give complex mixtures of products m which 4,4 dimethyl-l.l -biphenyl is a minor constituent A radical process maj also be involved in the formation of 4,4 dimethyl-1, l -biphenyl (13%) by treatment of 4-bromotoluene with hydrazine hydrate 5 4,4 -Dimethyl-l,l -biphenyl has been obtained in moderate to good yield (68-89%) by treatment of either dichlorobis(4-methyl phenyl)tellurium or l,l -tellurobis(4-methylbenzene) with degassed Raney nickel in 2 methoxyethyl ether 6... 

A complex reaction takes place when dichlorobis(triphenylphosphine)-nickel (5) is treated with excess methylmagnesium bromide in ether. Detectable amounts of benzene, toluene, and biphenyl are formed, together with mixed phosphines. Nickel appears to be necessary for the substitution reaction since triphenylphosphine alone does not react with the Grignard reagent. 

II), and gold(III) perhaloaryl complexes with the ligand bis(diphenylphosphino) amine. Crystal and molecular structure of m-[bis(diphenylphosphino)amine] dichlorobis(pentafluorophenyl)digold... 

Ge—metal bonds can be built in analogy as described for Ge—C bonds by the reaction of organolithium compounds with metal halides. With trans-dichlorobis(triethylphosphine)platinum(II), new germyl transition metal complexes were synthesized (equation 36)41. 

Fig. 11. Dependences of observed first-order rate constants on nucleophile concentration for thiocyanate susbtitution at dichlorobis(ethylmaltolato)meta-1(IV) complexes M(etmalt)2Cl2, and at a series of tin(IV) complexes SnL2Cl2 with L = the ligands whose formulae are shown against the thin line plots. The data refer to reactions in acetonitrile solution at 298.2 K (data from Refs. (264) and (265)).

C6Hi4Cl2N202Pt, Platinum(ll), cw-dichlorobis-(propanoneoxime)-, 34 82 C6Hi4Cl2N202Pt, Platinumfll), trani-dichloro-bis(propanoneoxime)-, 34 83 C6H18N4, tren, Tris(2-aminoethyl)amine, complex with copper(II), 34 138 CfiNNaOsW, Tungstate(O), pentacarbonylcyano-, sodium, 34 162... 

Treatment of 1-azirine (292) with catalytic quantities of dichlorobis(benzonitrile)pal-ladium(II) gave a quantitative yield of the indole (293) (77CC664). This transformation proceeds through the intermediacy of a 2 1 azirine-palladium chloride complex. Conversion of the 1-azirine ring to indoles under uncatalyzed thermolytic conditions provides a mechanistically interesting comparison with the Pd(II)-catalyzed conversions. The C—N bond cleavage in the latter is apparently accelerated as a result of the coordination of the azirine to palladium. 

The ESR spectra of a series of triarylboron anion radicals have been determined and show selective line-broadening effects (95). The radical anions of diborane, generated in an argon matrix at 77 K by irradiation with a-rays have been studied by ESR (121). The vanadium-aluminum complex obtained on mixing dichlorobis(7r-cyclopentadienyl)vanadium with ethylaluminum dichloride, a system that catalyzes the polymerization of ethylene to give a polymer with good characteristics, has been characterized by ESR and ultraviolet studies (44). 

Preparation of the complexes CdX2L2 (X = C1, Br, I or SCN L = acetamide) has been reported. IR evidence indicates bridging halide ligands, with L coordination via O and N.353 The crystal structure of dichlorobis(N,N-dimethyIacetamide)zinc shows zinc tetrahedrally... 

When [PdCl2(NCPh)2] was mixed with an excess of cycloheptatriene-thione the red dichlorobis(cycloheptatrienethione) complex [PdCl2 (771-SC7H6)2] precipitated. A cis configuration in the solid state was proposed. A cyclopalladated product was not observed.136... 

The facts that the phenylacetyl complex Villa also undergoes a reaction with phenylacetyl chloride under identical experimental conditions to yield dibenzyl ketone, XVIII (218% with respect to Villa), and that XVII was also obtained from the reaction of phenylacetyl chloride with dichlorobis(triphenylphosphine)palladium(0), XIX, implicate XIX in the catalytic cycle. The palladium (II) complex XIX does indeed catalyze the conversion of an acyl halide to the corresponding symmetrical ketone (123% with respect to XIX). The palladium (IV) structures are only... 

Tris (triphenylphosphine) nickel, tris (tri-p-tolylphosphine) nickel, and bis (1,3-diphenylphosphinepropane) nickel proved to be good catalysts, the first being slightly more effective. The tricyclohexylphosphine complex was a very poor catalyst, and bis (cyclooctadiene) nickel did not catalyze cyanation. Cyanation of several substituted aromatic halides in the presence of Ni[P(C6H5)3]3 prepared by reducing dichlorobis (triphenylphosphine) nickel (II) 2 with a powdered manganese iron (80 20) alloy (Reaction 3) is reported in Table II. 

Infrared and Raman spectra are useful, of course, in determining the symmetry of poly(nitrile) complexes. An example is dichlorobis(benzonitrile)platinum, a versatile starting material in platinum chemistry. There is a dispute in the literature as to whether it has a cis or trans configuration. (There is a general agreement that the corresponding Pd complex is trans.) It has recently been shown by X-ray structure analysis that both cis and trans complexes exist, and their vibrational spectra have been discussed.21... 

Pinacolone, o-(diphenylphosphino)benzoyl-coordination chemistry, 401 Piperidine, IV-hydroxy-metal complexes, 797 pA a values azole ligands, 77 Plant roots amino acids, 962 carboxylic acids, 962 Plastocyanin copper binding site, 557 copper(II) complexes, 772 copper(II) site in, 770 Platinum, dichlorobis(benzonitrile)-IR spectrum, 264 Platinum, cis-dichlorodianunine-antitumor activity, 34, 979 Platinum, ethylenebis(triphenylphosphine)-reactions with 5,6-dimethyl-2,l,3-benzothiadiazole, 194 Platinum blue formation, 265 Platinum complexes acetylacetone reactions, 380 amides, 491 amidines... 

PVP may react with dichlorobis(2,2 -bipyridyl)ruthenium(II) and the precomplexed polymer may then be used to dip coat various electrodes.52 EDTA complexes of ruthenium(III) will react with PVP and may thereby be immobilized on electrodes. The use of transparent graphite electrodes facilitates the spectroscopic monitoring of both the quantity of PVP and ruthenium on the electrode. Also the Ru111 -+ Ru11 reduction may be followed as it proceeds. The UV spectra of the immobilized EDTA complexes are similar to those in solution. It has been possible to use a band... 

Besides (carbonato)bis(ethylenediamine)cobalt(III) chloride and the corresponding bromide salt, the following complexes are described cis- and frara -dichlorobis(ethylenediamine)cobalt(III) chloride, cts-aquachlorobis(ethylenediamine)cobalt(III) sulfate, cis-bis(ethylenediamine)dinitrocobalt(III) nitrite, m-aquabis-(ethylenediamine)hydroxocobalt(III) dithionate, and cis-diaqua-bis(ethylenediamine)cobalt(III) bromide. 

To 27.5 g. (0.1 mole) of crude (carbonato)bis(ethylenediamine)-cobalt(III) chloride is added 200 ml. of 1.00 N hydrochloric acid. The carbonato complex is dissolved with evolution of carbon dioxide gas and formation of a red solution consisting primarily of the corresponding cw-diaqua species. The solution is evaporated in the steam bath until an almost dry paste has been formed. The purple residue is filtered and washed with three 20-ml. portions of ice-cold water. Drying in air yields 19.5 g. of purple crystals of cu-dichlorobis(ethylenediamine)cobalt(III) chloride. The mother liquor and the washings are again evaporated almost to dryness to yield a second crop of crystals, 5.9 g. The total yield is 25.4 g. (84% based on (carbonato)bis(ethylenediamine)cobalt(III) chloride). The analysis and the visible absorption spectrum of the two fractions are identical. Anal. Calcd. for [Co(en)2Cl2 ] C1 H20 Co, 19.42 N, 18.46 C, 15.82 Cl, 35.05 H, 5.98. Found Co, 19.50 N, 18.57 C, 15.77 C1, 35.15 H, 6.01. 

Disodium cw-bis(ethylenediamine)disuIfitocobaltate(III) nitrate and also the perchlorate have not been reported before and are recommended as sources of the cfs-bis(ethylenediamine)disulfito-cobaltate(III) ion, which has been prepared by Baldwin1 by proceeding through a difficult series of complex salts. The m-azidobis(ethylenediamine)sulfitocobalt(III) is also newly reported it can be converted into a relatively pure sodium ran.y-bis(ethylenediamine)disulfitocobaltate(III), which has previously been made from dichlorobis(ethylenediamine)cobalt(III) chloride1 and tetraammine(carbonato)cobalt(III) chloride.2... 

The synthesis and reactivity of a series of nickelacyclopentane compounds with a range of tertiary phosphine ligands was reported by Grubbs et ol. Compounds of type 69 were prepared by the reaction of 1,4-dilithiobutane with the appropriate dichlorobis(tertiaryphosphine)nickel(II) complex, and isolated as yellow crystals in ca. 40% yield78 (dppe = bis(diphenyl) (phosphinoethane). 

Albanese, J. A. Staley, D. L. Rheingold, A. L. Burmeister, J. L. Synthesis and molecular structure of a dinuclear phosphorus ylide complex /t-dichlorobis[chloro(benzoylmeth-ylenetri-u-butylphosphorane) palladium(I I). 

The crystal structure of trans-dichlorobis(AT-methylsalicylaldiminato)molyb-denum(iv) has been determined and the compound shown to consist of discrete monomeric units which have a crystallographic centre of symmetry. The bonds involving the metal atom, Mo—O, Mo—N, and Mo—Cl, are 195, 214, and 239 pm, respectively.437 The complex [Mo(SCN)2(H20)L] [H2L = AT-(salicylidene)-2-hydroxybenzamine] has been prepared and its i.r. and electronic spectra recorded.430... 

The crystal structures of the cadmium complexes bis(L-methionato) cadmium(n), bis(L-asparaginato) cadmium(n), triaqua-bis-(L-glutamato)dicadmium(n) hydrate, dichlorobis(glycylglycine)cadmium(ii), aquachloro(glycylglycinato)cadmium(ii) and aqua(L-glutamato)cadmium(n) hydrate have been reported.265 Several distinct binding interactions are in evidence. 

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