V. N. Kalinin

Preparation of transition metal isoxazole derivatives

η1-Ethynyl complexes Cp(CO)nLMCCPh (n = 1, 2; L = CO, PPh3; M = Fe, Mo) react with nitrile oxides RCN → O (R = Ph, CO2Et) to give the σ-isoxazolyl transition metal derivatives Cp(CO)nLMCC(Ph)C(R)NO, which have been characterized by IR and 1H NMR spectroscopy. An X-ray diffraction study of Cp(OC)(Ph3P)FeCC(Ph)C(Ph)NO is described.

Structures, dynamic behaviour in solution and cross-coupling reactions of the α-palladiated (η6-alkylarene)tricarbonylchromium complexes containing a palladium-chromium bond

Abstract Structures of the complexes ( η 3 -C 3 H 5 )Pd( μ - η 6:1 -CH 2 Ph Cr ( CO ) 3 and ( η 3 -C 3 H 5 )Pd[ μ - η 6:1 -CH(Ph)Ph]Cr(CO) 3 in solution were evaluated by NMR ( 1 H and 13 C) and IR spectroscopy. The dynamic behaviour of the complexes was investigated. Quick rotation (on the NMR time scale) of the tricarbonylchromium groups around the axis passing through the centre of the η 6 -coordinated phenyl ring and the chromium atom takes place at room temperature and becomes slow on cooling. The η 3 -allylic ligand was proved to undergo no dynamic changes in solution. Unlike the solid state, the semi-bridging carbonyl groups between chromium and palladium atoms are absent or very weak in solution. Cross-coupling reactions of the complexes with organohalides are described.

2-η3-allyl-1,1,1-tricarbonyl-μ-(η1:η6-diphenylmethyl)chromiumpalladium(Pd-Cr) at 130 K

The introduction of the phenyl substituent at the benzyl C atom of the arene, π-coordinated by the Cr atom, does not cause any significant changes in the geometry of the binuclear complex which contains a direct Pd-Cr bond [average length 2.768(1) A for the two independent molecules]. The Pd-C benzyl , Pd-C ipso and C benzyl -C ipso bond lengths [averages 2. 138(3), 2.547(2) and 1.452(3) A, respectively] and other geometric features indicate that the title compound may be treated as a superposition of two canonical structures, one of which implies π coordination of the Pd atom by the exocylic C benzyl -C ipso bond whereas the second involves only Pd-C benzyl σ bonding

Arenetricarbonylchromium complexes in the synthesis of 6,7-benzomorphanes

Abstract The action of sodium amide on tricarbonyl-η 6 -[1′,2′,3′,4′-tetrahydro-spiro(1,3-dioxolane-2,1′-naphthalene)]chromium followed by reaction with sodium bromoacetate gives tricarbonyl-η 6 -[1-(1,2,3,4-tetrahydro-4-oxonaphthalene)acetic acid]chromium ( 4 ). Some procedures to transform 4 into 1-( N -benzyl-2-aminoethyl)-1,2-dihydronaphthalene ( 10 )—a synthon to 6,7-benzomorphanes—are described. Cyclization of 10 by action of mercury(II) acetate yields 3-benzyl-1,2,3,4,5,6-hexahydro-1-hydroxy-2,6-methano-3-benzazocine ( 11 ).

Sydnonimines as exogenous NO donors

Chemical oxidation of a series of sydnonimine derivatives followed by NO release was studied. Substances having alkylamine substituents in the position 3 were shown to be considerably more potent NO donors in comparison with those having alkyl or aralkyl substituents in the position 3. It was suggested that the effect is mainly due to lowering of the activation energy of NO release upon stabilization of the cation formed competitevely by the amino group.

Palladium-catalyzed asymmetric allylation and complex formation involving P,N-bidentate derivatives of (S)-2-(anilinomethyl)pyrrolidine

P,N-Bidentate (S)-2-(anilinomethyl)pyrrolidine derivatives and their complexes with rhodium(i) and palladium(ii) were synthesized. It was demonstrated that these compounds can be used in the Pd-catalyzed asymmetric allylation for the synthesis of chiral methyl 2-phenyl-2-(2-phenyl-o-carboranyl-1)pent-4-enoate.

Synthesis ofN-phenyl-substituted derivatives of morphine alkaloids

A method for the preparation ofN-phenyl-substituted morphine alkaloids by treatment of the correspondingN-nor derivatives with Ph3Bi in the presence of Cu(OAc)2 is proposed. 17-Nor-17-phenylthebaine thus obtained can serve as a convenient starting material for the preparation of otherN-phenyl-substituted alkaloids.

Iridium-catalyzed regiospecific allylation of dimethyl malonate in ionic liquids

Allylation of dimethyl malonate with 1-(4-chlorophenyl)prop-2-enyl methyl carbonate in the presence of [Pd(All)Cl]2, [Rh(COD)Cl]2, [Ir(COD)Cl]2 (COD is cycloocta-1,5-diene), and a chiral ferrocenyl-containing phosphite ligand based on (R)-BINOL (BINOL is 2,2′-dihydroxy-1,1′-binaphthyl) in CH2Cl2 gave a mixture of linear and branched cross-coupling products, the latter having a moderate optical purity (below 51%). The rhodium-and iridium-catalyzed reactions were very highly regioselective (regiospecific in the case of Ir), giving a branched product. In ionic liquids ([bmim][BF4] and [bdmim][BF4]) (bmim is 1-butyl-3-methylimidazolium and bdmim is 1-butyl-2,3-dimethylimidazolium), the Ir-catalyzed reaction regiospecifically afforded a branched product as a racemate. The same result was obtained with [Ir(COD)Cl]2 as a catalyst; this reaction easily occurred in ionic liquids even without a base.

Molecular and crystal structures of (6R, 7R, 14S)-6,14-etheno-7-[(1R)-1-hydroxyethyl]- and (6R, 7R, 14S)-6,14-etheno-7-[(1S)-1-hydroxyethyl]-6,7,8,14-tetrahydro-17-nor-17-phenylthebaine

The crystal structures and absolute configurations of (6R,7R,14S)-6,14-etheno-7-[(1R)-1-hydroxyethyl]-6,7,8,14-tetrahydro-17-nor-17-phenylthebaine and (6R,7R,14S)-6,14-etheno-7-[(1S)-1-hydroxyethyl]-6,7,8,14-tetrahydro-17-nor-17-phenylthebaine were established by X-ray diffraction analysis.

3-Lithiomethyl-4-phenylsydnone: A new type of organometallic derivatives of sydnones

An α-lithium derivative of 3-alkyl-substituted sydnone was first synthesized by direct metallation of 3-methyl-4-phenylsydnone withn-butyllithium. The reactivity of the compound obtained was studied. Reactions of 3-lithiomethyl-4-phenylsydnone with various electrophiles can serve as a convenient method for preparation of functionalized sydnones.