Construction of α-phosphonolactams via rhodium (II)-catalyzed intramolecular C?H insertion reactions

The Rh(II)-catalyzed intramolecular C H insertion reactions of N,N-dialkyl-α-diazo-α-(diethylphosphono)acetamides 2a , f–j in CHCl₃ or ClCH₂CH₂Cl were found to give monocyclic and bicyclic α-phosphono-β-lactams, 3a and 3f–j , in 43–67% yields via regiospecific α-C H insertion of the N-alkyl groups. Similar treatment of N-benzyl-N-isopropyl-α-diazo-α-(diethylphosphono)acetamide ( 2b ) and the corresponding N-isobutyl-N-methylacetamide 2d in ClCH₂CH₂Cl afforded mixtures of β-lactams 3b (35%) and and 3b ′ (16%), β-lactam 3d (47%), and γ-lactam 4d (10%), respectively, each of which is formed by the competitive C H insertion reaction between benzylic and isopropyl α-C H bonds and between methyl α-C H and methine β-C H bonds, respectively. For the formation of β-lactams, the selectivity in the rhodium-mediated C H insertion in ClCH₂CH₂Cl follows the order methyl > methine > benzylic α-C H bond on N-substituents. The N,N-dibutyl-α-diazo homologue 2c and Nα[α-diazo-α-(diethylphosphono)acetyl]-2-methylindoline ( 2k ) exclusively produced γ-lactams 4c (67%) and 4k (81%) via insertion into the methylene β-C H and methyl β-C H bonds. tert-Butyl N-[α-diazo-α-(dibenzylphosphono)acetyl]-piperidine-2-carboxylate ( 2m ) on similar treatment, followed by deprotection of the benzyl ester afforded the 7-phosphono carbacepham 6 in 32% overall yield. Similar Rh(II)-catalyzed cyclization of N-methyl-N[4-benzyloxy-α-(diethylphosphono)-phenyl(diethyl-phosphono)methyl]-α-diazo-acetamide ( 2n ) led to 1-[4′-benzylphenyl(diethylphosphono)methyl] -3-(diethyl-phosphono)azetidin-2-one ( 3n ) in 78% yicld. The phosphono group at C-7 of 3f was converted into the acetylamino group via a four-step reaction. Application of chiral rhodium(II) carboxylates 12a–c to the insertion reactions of 2b , c produced α-phosphono-β-and γ-lactams, 3b and 4c , in 6–24% ee and 25–29% ee, respectively.     

Synthesis and properties of novel polymers having S-methyldibenzothiophenium salt moieties

A polymer having dibenzothiophenium salt moieties [poly(sulfonium salt), 2 ] was prepared by the reaction of poly(2-vinyldibenzothiophene) ( 1 ) with CH₃I and AgBF₄ in CH₂ClCH₂Cl at room temperature for 24 h. The obtained polymer 2 was found to contain 71% of the methyldibenzothiophenium tetrafluoroborate unit. A monomer carrying the sulfonium salt moiety, i.e., 5-methyl-2-vinyldibenzothiophenium tetrafluoroborate ( 4 ), was independently prepared and subjected to radical polymerization to give a polymer ( 5 ) in 88% yield (methyldibenzothiophenium tetrafluoroborate unit: 79%). The thermal decompositions of 2 and 5 took place in two steps; the first step involved the formation of polymer 1 by demethylation. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1779–1784, 1998     

The ethyl halides: Stable neutral and radical cation isomers [C2, H2, X] where X = F,Cl, Br,I

The following isomers of the ethyl halide molecular ions have all been shown to be stable species in the gas phase: [CH₂CH₂FH]⁺˙; [CH₃ClCH₂]⁺˙ (ΔH_f° = 1012 kJ mol^?1); [CH₃CHClH]⁺˙ (ΔH_f° = 971 kJ mol^?1); [CH₂CH₂ClH]⁺˙; [CH₃BrCH₂]⁺˙ (ΔH_f° = 1058 KJ mol^?1); [CH₃CHBrH]⁺˙ (ΔH_f° = 995 kJ mol^?1) and [CH₂CH₂BrH]⁺˙. Neutralization–reionization mass spectrometry, employing Xe as the electron transfer target gas and O₂ as the target gas for reionization, indicated that the ylides CH₃ClCH₂ and CH₃BrCH₂ could not be generated by such means. However, the species CH₃CHClH, CH₂CH₂ClH and CH₂CH₂BrH (and possibly CH₃CHBrH) were unambiguously identified.     

Organic Phosphorus Compounds 52. Preparation and properties of β-hydroxyalkyl-phosphonium salts and tertiary phosphine oxides

The new, tris- (2- hydroxyalkyl) - (hydroxymethyl) - phosphonium salts: [(RCHOHCH₂)₃ PCH₂OH]Cl (I, R = ClCH₂; III, R = CH₃) are formed in high yield by reaction of tetrakis-(hydroxymethyl)-phosphonium chloride (Tetrakis) with epoxides under basic conditions. Under the same conditions, styrene oxide yields only the disubstituted product, [(PhCHOHCH₂)₂ (CH₂OH)₂P]Cl. Optimal pH values for the reactions are 8 to 9; at lower pH the conversion is too slow; at a higher pH, oxidative decomposition of the salts occurs. Conversion of the salts to tertiary phosphine oxides (RCHOHCH₂)₃P ? O (R ? ClCH₂; CH₃) with loss of the hydroxymethyl group is best carried out with chlorine at pH 5 to 7. The yields are usually 60 to 90%.     

Synthesis of N-[chloro(diorganyl)silyl]anilines

A series of N-[chloro(diorganyl)silyl]anilines RR′Si(NR″Ph)Cl (R, R′ = Me, Ph, CH₂=CH, ClCH₂, Cl(CH₂)₃; R″ = H, Me) was prepared via the reaction of diorganyldichlorosilanes with aniline or N-ethylaniline in the presence of triethylamine.     

1-organyl-3-(2-vinyloxyethoxymethyl)silatranes

Conclusions The reaction of N-[2-hydroxy-2-(2-vinyloxyethoxymethyl)ethyl]-bis(2-hydroxyethyl)amine with organyltriethoxysilanes at 20–40°C gave previously unreported 1-organyl-3-(2-vinyloxy-ethoxymethy)silatranes, (R=CH₃, ClCH₂, CH₂=CH, C₆H₅, C₂H₅O).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 740–742, March, 1989.     

Preparation,properties and reactivities of novel platinum compounds containing a thiomethoxymethyl group

Oxidative addition of ClCH₂SCH₃ to PtL₄ afforded trans-PtL₂(CH₂SCH₃)Cl (Ia, L = Ph₃P;Ib, L = MePh₂P). Treatment of I with NH₄PF₆ or Et₃OBF₄ in CH₂C1₂ gave ionic species, [PtL₂(CH₂SCH₃)]X (II, L = Ph₃P, MePh₂P, X = BF₄, PF₆), while similar treatment with MeSO₃F in benzene yielded a new type of stable dimethylsulfonium methylide—platinum complex, trans-[PtL₂(CH₂SMe₂)Cl] SO₃F (IIIa, L = Ph₃P; IIIb, L = MePh₂P). Action of H₂O₂ on Ia gave [Pt(Ph₃P)(μ-CH₂SCH₃)C1]₂ (IV) and its triphenylarsine analog, [Pt(Ph₃As)(μ-CH₂SCH₃)C1]₂ (V) was prepared in one step by oxidative addition of ClCH₂SCH₃ to Pt(AsPh₃)₄. The structural difference between [Pt(Ph₃P)(μ-CH₂SCH₃)C1]₂ and Pd(Ph₃P)- (CH₂SCH₃)C1 is discussed in terms of the difference in the ionization potential from d¹⁰ to d⁸ electronic state of metals.     

Maximum overlap approximation calculations on polyatomic molecules: IV. Saturated haloalkanes

The extended maximum overlap approximation (EMOA) method has been applied to a series of fluorine and chlorine derivatives of some alkanes in the present communication. Strictly localized molecular orbitais for 34 molecules have been constructed explicitly from hybrid atomic orbitals on IEHT level of approximation. The calculated heats of formation and dipole moments are in remarkable agreement with experimental data. Results are comparable with MENDO/3 and CNDO/2 calculations, respectively. Charge distributions show that the electron withdrawing effect of the halogen extends throughout the molecular skeleton with decreasing intensity; the inductive effects of the groups +I [CH₃—] < +I [CH₃CH₂-] < +I [CH₃CH₂CH₂-] < +I [(CH₃)₂CH—] < +I [(CH₃)₃C—] (positive) and —I [F—] > —I [Cl—] (negative) are perfectly reproduced. The s-electron density on carbon and proton in C—H bond correlates with the experimental carbon-13—proton nuclear spin-spin coupling constant in the series of some chloroethanes.     

Cyclische Ester von Phosphin- und Thiophosphinsäuren

Zusammenfassung Chlormethyl-methyl-phosphinsäurechlorid (ClCH₂)(CH₃)P(O)Cl und Chlormethyl-methyl-thiophosphinsäurechlorid (ClCH₂)(CH₃)-P(S)Cl reagieren mit aromatische 1,2-Diolen wie Brenzcatechin, mit o-Aminophenol, o-Aminothiophenol und Toluol-3,4-dithiol unter Substitution der beiden Chloratome zu den entsprechenden Benzophosphorinanen.

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(ClCH₂)(CH₃)P(O)Cl and (ClCH₂)(CH₃)P(S)Cl react with aromatic diols like catechol, o-aminophenol, o-aminothiophenol and toluene-3,4-dithiol with the formation of benzophosphorinanes.

     

Hydrolysis and Oxidation Products of the Chemical Warfare Agents 1,2-Bis[(2-chloroethyl)thio]ethane Q and 2,2′-Bis(2-chloroethylthio)diethyl Ether T

Syntheses of diols of structure [HOCH₂CH₂S]₂(CH₂)_n in 86–95% yield from the sodium salt of 2-mercaptoethanol and Br(CH₂)_nBr (n = 1 to 5) or in 60–90% yield from 2-chloroethanol and NaS(CH₂)_nSNa (n = 2 to 5) are described. The diol [HOCH₂CH₂SCH₂CH₂]₂O was prepared in 82% yield from the sodium salt of 2-mercaptoethanol and [ClCH₂CH₂]₂O, and in 88% yield from 2-chloroethanol and [HSCH₂CH₂]₂O. Mono- and bis-sulfoxides and bis-sulfones of these species were prepared in generally high yield by treatment with an equivalent of KIO₄ in aqueous methanol, two equivalents of NaIO₄ in aqueous methanol, or four equivalents of H₂O₂ in trifluoroacetic acid respectively. The compounds are important analytical standards for investigating the fate of the chemical warfare agents sesquimustard Q and oxygen mustard T in environmental samples.     

Synthesis of 2-amino-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene and some transformations based on it

A new method for the synthesis of 2-amino-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene was developed. The reaction of the latter with allyl isothiocyanate gave 2-(N-allylthioureido)-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene, which is cyclized to the potassium salt of 3-allyl-4-oxo-2-thio-3,4,5,6,7,8-hexahydrobenzo[b]selenopheno[2,3-d]pyrimidine on treatment with potassium hydroxide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 326–328, March, 1973.     

Complex Formation in the System Bis[2-(trimethylammonio)ethyl] Succinate Diodide-Iodine in Solutions and in Crystal

The complex formation in the system bis[2-(trimethylammonio)ethyl] succinate diodide-iodine involves no more than two iodine molecules. The crystal structure of the salt [(CH3)3N(CH2)2OCOCH2]2(I3)2 is formed by layers of inorganic anions (I₃ ^-) and organic dications (centrosymmetric dications {[(CH₃)₃N · (CH₂)₂OCOCH₂]⁺}₂), evenly alternating along the a axis. The crystal structure of the salt [(CH₃)₃N(CH₂)₂·OCOCH₂]₂(I₃)₂(I₂)0.5 is formed by organic and inorganic layers evenly alternating along the [011] diagonal, with a centrosymmetric iodine molecule.     

Dibenz [b,f]-1, 4-oxazepin-11 (10 H)-one und Dibenz [b,e]-1, 4-oxazepin-11 (5 H)-one. 12. Mitteilung über siebengliedrige Heterocyclen

The syntheses of dibenzo [b, f]-1, 4-oxazepin-11 (10 H)-ones (I) with electron-attracting substituents in position 2 by ring closure of the sodium salts of 2-halogeno-2′-hydroxy-benzanilides (II) are described. The reaction of II (R = SO₂·N(CH₃)₂) in N-methylpyrrolidone also led, by SMILES rearrangement, to the isomeric minor product dibenzo [b, e]-1, 4-oxazepin-11 (5 H)-one (III; R = SO₂·N(CH₃)₂), whose constitution was proven by synthesis from VI. In the case of II (R = SO₂·CH₃), the 5-methylsulfonyl-2-(2-hydroxyanilino)-benzoic acid (VI; R = SO₂·CH₃) was obtained directly after hydrolysis. The lactam I (R = NO₂) was rearranged to the corresponding acid VI by heating with dilute caustic soda.     

Organische Phosphorverbindungen 44 Darstellung und Eigenschaften von Bis-(ß-chloräthyl)-phosphinsäure-Derivaten [1]

Reaction of ClCH₂CH₂PCl₂ with ethylene oxide gives the phosphonous acid ester ClCH₂CH₂P (OCH₂CH₂Cl)₂ which on heating to 120° rearranges to the phosphinic acid ester (ClCH₂CH₂)₂P(O)OCH₂CH₂Cl ( 3 ). Chlorination of 3 with PCl₅ in CCl₄-solution yields the phosphinic chloride (ClCH₂CH₂)P(O)Cl ( 4 ), which on treatment with P₂S₅ at 170° produces the thioderivative, (ClCH₂CH₂)₂P(S)Cl, (₅). Treatment of 4 and 5 with alcohols, mercaptanes, or amines in the presence of an acid binding agent leads to the corresponding phosphinic and thiophosphinic acid derivatives, (ClCH₂CH₂) P (X)Y, (X = O, S; Y = OR, SR, NR₂) ( 6 ). Reaction of 6 with excess base yields the corresponding divinylphosphinic and divinylthiophosphinic acid derivatives (CH₂ = CH)₂P (X) Y (X = O, S; Y = OR, SR, NR₂) ( 7 ). Bis-(ß-chloroethyl)-phosphinates, e. g. (ClCH₂CH₂)₂P (O) OEt, undergo a Michaelis-Arbuzov reaction when heated with phosphites to 160–170° to give bis-(phosphonylethyl)-phosphinates, e.g. (EtO) (O)P[CH₂CH₂CH₂P(O)(OEt)₂]₂ ( 8 ), which on hydrolysis with conc. HCl under reflux yield the corresponding acid HO₂P(CH₂CH₂PO₃H₂)₂.     

Brominated trimetrexate analogues as inhibitors of pneumocystis carinii and toxoplasma gondii dihydrofolate reductase

Five previously undescribed trimetrexate analogues with bulky 2′-bromo substitution on the phenyl ring were synthesized in order to assess the effect of this structure modification on dihydrofolate reductase inhibition. Condensation of 2-[2-(2-bromo-3,4,5-trimethoxyphenyl)ethyl]-1,l-dicyanopropene with sulfur in the presence of N,N-diethylamine afforded 2-amino-5-(2′-bromo-3′,4′,5′-trimethoxybenzyl)-4-methyl-thiophene-3-carbonitrile ( 15 ) and 2-amino-4-[2-(2′-bromo-3′,4′,5′-trimethoxyphenyl)ethyl]thiophene-3-car-bonitrile ( 16 ). Further reaction with chloroformamidine hydrochloride converted 15 and 16 into 2,4-diamino-5-(2′-bromo-3′,4′,5′-trimethoxybenzyl)-4-methylthieno[2,3-d]pyrimidine ( 8a ) and 2,4-diamino-4-[2-(2′-bromo-3′,4′,5′-trimethoxyphenyl)ethylthieno[2,3-d]pyrimidine ( 12 ) respectively. Other analogues, obtained by reductive coupling of the appropriate 2,4-diaminoquinazoline-6(or 5)-carbonitriles with 2-bromo-3,4,5-trimethoxyaniline, were 2,4-diamino-6-(2′-bromo-3′,4′,5′-trimethoxyanilinomethyl)-5-chloro-quinazoline ( 9a ), 2,4-diamino-5-(2′-bromo-3′,4′,5′-trimethoxyanilinomethyl)quinazoline ( 10 ), and 2,4-diamino-6-(2′-bromo-3′,4′,5′-trimethoxyanilinomethyl)quinazoline ( 11 ). Enzyme inhibition assays revealed that space-filling 2′-bromo substitution in this limited series of dicyclic 2,4-diaminopyrimidines with a 3′,4′,5′-trimethoxyphenyl side chain and a CH₂, CH₂CH₂, or CH₂NH bridge failed to improve species selectivity against either P. carinii or T. gondii dihydrofolate reductase relative to rat liver dihydrofolate reductase.     

P−P Condensation and P−N/P−P Bond Metathesis: Facile Synthesis of Cationic Tri- and Tetraphosphanes

[L_C^RP((PhP)₂C₂H₄)][OTf] ( 4 a,b [OTf]) and [L_C^iPrP(PPh₂)₂][OTf] ( 5 b [OTf]) were prepared from the reaction of imidazoliumyl-substituted dipyrazolylphosphane triflate salts [L_C^RP(pyr)₂][OTf] ( 3 a,b [OTf]; a : R=Me, b =iPr; L_C^R=1,3-dialkyl-4,5-dimethylimidazol-2-yl; pyr=3,5-dimethylpyrazol-1-yl) with the secondary phosphanes PhP(H)C₂H₄P(H)Ph) and Ph₂PH. A stepwise double P−N/P−P bond metathesis to catena-tetraphosphane-2,3-diium triflate salt [(Ph₂P)₂(L_C^MeP)₂][OTf]₂ ( 7 a [OTf]₂) is observed when reacting 3 a [OTf] with diphosphane P₂Ph₄. The coordination ability of 5 b [OTf] was probed with selected coinage metal salts [Cu(CH₃CN)₄]OTf, AgOTf and AuCl(tht) (tht=tetrahydrothiophene). For AuCl(tht), the helical complex [{(Ph₂PPL_C^iPr)Au}₄][OTf]₄ ( 9 [OTf]₄) was unexpectedly formed as a result of a chloride-induced P−P bond cleavage. The weakly coordinating triflate anion enables the formation of the expected copper(I) and silver(I) complexes [( 5 b )M(CH₃CN)₃][OTf]₂ (M=Cu, Ag) ( 10 [OTf]₂, 11 [OTf]₂).     

Organische Phosphorverbindungen 39. Methoden zur Herstellung von Chloräthylphosphonsäuredichlorid,ClCH2CH2P(O)Cl2 und CH3CHClP(O)Cl2 [1]

It is shown that the KINNEAR -PERREN reaction with ClCH₂CH₂Cl, PCl₃, and AlCl₃ produces the two possible isomers ClCH₂CH₂P(O)Cl₂ and CH₃CHClP(O)Cl₂. Methods for the preparation of pure ClCH₂CH₂P(O)Cl₂ and pure CH₃CHClP(O)Cl₂ are described. The physical properties of a number of chloroethyl groups containing phosphorus compounds are listed.     

Charge-Transfer Salts of Ferrocene Derivatives with Bis(maleonitriledithiolato)metallate(III) Complexes ([M(mnt)2]−, M=Ni,Pt): A Ground-State High-Spin [(Ni(mnt)2)2]2− Dimer

New hexamethylated ferrocene derivatives containing thioether moieties (1,1′-bis[(tert-butyl)thio]-2,2′,3,3′,4,4′-hexamethylferrocene ( 3a , b )) or fused S-heteropolycyclic substituents (rac-1-[(1,3-benzodithiol- 2-yliden)methyl]-2,2′,3,3′,4,4′-hexamethylferrocene ( 5 ) and rac-1-[1,2-bis(1,3-benzodithiol-2-yliden)ethyl]-2,2′,3,3′,4,4′-hexamethylferrocene ( 14 )), as well as a series of ferrocene-substituted vinylogous tetrathiafulvalenes (1,1′-bis[1,2-bis(1,3-benzodithiol-2-yliden)ethyl]ferrocene ( 6a ), 1,1′-bis[1-(1,3-benzodithiol-2-yliden)-2-(5,6-dihydro-1,3-dithiolo[4,5-b] [1,4]dithiin-2-yliden)ethyl]ferrocene ( 6b ), [1,2-bis(1,3-benzodithiol-2-yliden)ethyl]ferrocene ( 21a ), [1-(1,3-benzodithiol-2-yliden)-2-(5,6-dihydro-1,3-dithiolo[4,5-b] [1,4]dithiin-2-yliden)ethyl]ferrocene ( 21b ), [1,2-bis(5,6-dihydro-1,3-dithiolo[4,5-b] [1,4]dithiin-2-yliden)ethyl]ferrocene ( 21c ), [1-(5,6-dihydro-1,3-dithiolo[4,5-b] [1,4]dithiin-2-yliden)-2-(1,3-benzodithiol-2-yliden)ethyl]ferrocene ( 21d )) were prepared and fully characterized. Their redox properties show that some of them are easily oxidized and undergo transformation to paramagnetic salts containing bis(maleonitriledithiolato)-metallate(III) anions [M(mnt)₂]⁻ (M=Ni, Pt; bis[2,3-dimercapto-κS)but-2-enedinitrilato(2⁻)]nickelate (1⁻) or -platinate (1⁻). The derivatives [ 3a ] [Ni(mnt)₂] ( 26 ), [ 3a ] [Pt(mnt)₂] ( 27 ), [Fe{(η⁵-C₅Me₄S)₂S}] [Ni(Mnt)₂] ( 28 ), [Fe{(η⁵-C₅Me₄S)₂S}] [Pt(mnt)₂] ( 29 ), [ 5 ] [Ni(mnt)₂]⋅ClCH₂CH₂Cl ( 30 ), [ 6a ] [Ni(mnt)₂] ( 31 ), [ 6a ] [Ni(mnt)₂]⋅ClCH₂CH₂Cl ( 31a ), [ 6a ] [Pt(mnt)₂] [ 32 ), and [ 6b ] [Ni(mnt)₂] ( 33 ) were prepared and fully characterized, including by SQUID (superconducting quantum interference device) susceptibility measurements. X-Ray crystal-structural studies of the neutral ferrocene derivatives 6a , b , 21c , d , and 1,1′-bis[1-(1,3-benzodithiol-2-yliden)-2-oxoethyl]ferrocene ( 23 ), as well as of the charge-transfer salts 26 – 28 , 30 , and 31a , are reported. The salts 28 and 30 display both a D⁺A⁻A⁻D⁺ structural motif, however, with a different relative arrangement of the [{Ni(mnt)₂}₂]²⁻ dimers, thus giving rise to different but strong antiferromagnetic couplings. Salt 26 exhibits isolated ferromagnetically coupled [{Ni(mnt)₂}₂]²⁻ dimers. Salt 27 displays a D⁺A⁻D⁺A⁻ structural motif in all three space dimensions, and a week ferromagnetic ordering at low temperature. Salt 31a , on the contrary, shows segregated stacks of cations and anions. The cations are connected with each other in two dimensions, and the anions are separated by a 1,2-dichloroethane molecule.     

On the regioselectivity of alkylation of the (trimethylsilyl)tetramethylcyclopentadienide anion. A new approach to the synthesis of 1,2,3,4-tetramethylfulvene

The regioselectivity of alkylation of lithium (trimethylsilyl)tetramethylcyclopentadienide C₅Me₄SiMe₃ ⁻Li⁺ was studied by ¹H and ¹³C NMR spectroscopy using its reactions with MeI, MeOTs, ClCH₂CH₂Br, and ClCH₂CH₂I in different solvents as representative examples. Sterically non-hindered MeI and MeOTs presumably attack the C atom bonded to the silyl group giving 1,2,3,4,5-pentamethylcyclopentadienylsilane. For bulkier alkyl halides, such as ClCH₂CH₂Br and ClCH₂CH₂I, the regioselectivity of alkylation changes to form preferentially gem-dialkyl-substituted cyclopentadienes. The reaction of C₅Me₄SiMe₃ ⁻Li⁺ with formaldehyde affords 1,2,3,4-tetramethylfulvene in a high yield, providing an alternative synthetic approach to a number of ω-functionalized peralkylated cyclopentadienes. The quantum-chemical calculations of the C₅Me₄SiMe₃ ⁻ anion by the RHF and DFT (RMPW1PW91) methods in the valence-split 6-311+G(d,p) basis set are in good agreement with the experimental data.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2089–2093, October, 2004.     

Oxidation of coordinated olefins: the reactions of Cl2 with trichloro(ehtylene)platinate(II)

The oxidation of [PtCl₃(C₂H₄)]- by Cl₂ in aqueous solution, to yield CH₂ClCH₂OH and [PtCl₄]^2-, has been shown to proceed through the following sequence of steps: [PtCl₃(C₂H₄)] Cl₂Cl [PtCl₅(CH₂CH₂Cl)]^2-$\text{H}{}_2\text{O}\text{(HCl)}$ [PtCl₅(CH₂CH₂OH)]^2- → [PtCl₄^2- + CH₂ClCH₂OHEach of the steps and intermediates in this mechanistic sequence has been identified and characterized.