Conformational Analysis, Infrared, and Fluorescence Spectra of 1-Phenyl-1,2-propandione 1-oxime and Related Tautomers: Experimental and Theoretical Study

Conformational analysis and frequency calculation were achieved for 1-phenyl-1,2-propandione 1-oxime and its four tautomers: 1-nitroso-1-phenyl-1-propen-2-ol, 1-nitroso-1-phenyl-2-propanone, 2-hydroxy-1-phenyl-propenone oxime, and 3-nitroso-3-phenyl-propen-2-ol. Calculations were carried out at the Hartree–Fock (HF), Density Functional Theory (B3LYP), and the second-order M?ller–Plesset perturbation (MP2) levels of theory using 6-31G^* and 6-311G^** basis sets. Five conformers with no imaginary vibrational frequency were obtained by free rotations around three single bonds of 1-phenyl-1,2-propandione-1-oxime: Ph–C(NOH)C(O)CH₃, PhC(NOH)–C(O)CH₃, and PhC(N–OH)C(O)CH₃. Similarly, eight structures with no imaginary vibrational frequency were encountered upon rotations around three single bonds of 1-nitroso-1-phenyl-1-propen-2-ol: Ph–C(NO)C(OH)CH₃, PhC(N–O)C(OH)CH₃, and PhC(NO)C(–OH)CH₃. In the same manner, six minima were found through rotations around three single bonds of 1-nitroso-1-phenyl-2-propanone: Ph–CH(NO)C(O)CH₃, PhCH(–NO)C(O)CH₃, and PhCH(NO)–C(O)CH₃. Also, two minima were found through rotations around four single bonds of 2-hydroxy-1-phenyl-propenone oxime: Ph–C(NOH)C(OH)CH₂, PhC(N–OH)C(OH)CH₂, PhC(NOH)–C(OH)CH₂, and Ph-C(NOH)C(–OH)CH₂. Finally, two minima were found through rotations around four single bonds of 3-nitroso-3-phenyl-propen-2-ol: Ph–CH(NO)C(OH)CH₂, PhCH(–NO)C(OH)CH₂, PhCH(NO)–C(OH)CH₂, and PhCH(NO)C(–OH)CH₂. Interconversions within the above sets of conformers were probed through scanning (one and/or two dimensional), and/or QST3 techniques. The order of the stability of global minima encountered was: 1,2-propandione-1-oxime > 1-nitroso-1-phenyl-2-propanone > 1-nitroso-1-phenyl-1-propen-2-ol > 2-hydroxy-1-phenyl-propenone oxime > 3-nitroso-3-phenyl-propen-2-ol. Hydrogen bonding appears significant in tautomers of 1-nitroso-1-phenyl-1-propen-2-ol and 2-hydroxy-1-phenyl-propenone oxime. The CIS simulated λ_max for the first excited singlet state (S₁) of 1-phenyl-1,2-propandione 1-oxime is 300.4 nm, which was comparable to its experimental λ_max of 312.0 nm. The calculated IR spectra of 1-phenyl-1,2-propandione 1-oxime and its tautomers were compared to the experimental spectra.     

Alkylation of salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides with alkyl halides and dimethyl sulfate

Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH₂N(O)=NO⁻ M⁺ (R=Me, Prⁱ, or Bu^t; and M=Li, Na, K, Ag, NH₄, or Me₄N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH₂N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH₂N(NO)OR′. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998.     

Fluorosubstituted rhodacarboranes 3,4-(R3P)2-3-H-3,1,2-RhC2B9H11−n F n (n=1, 2, 4): Synthesis, molecular structure, and catalytic properties in hydrosilylation of styrene and phenylacetylene

Hydridorhodacarboranes 3,3-(Ph₂RP)₂-3-H-3,1,2-RhC₂B₉H_11−n F _n (R=Ph, Me;n=1, 2, 4) containing F atoms at the B atoms of the π-carborane ligand were synthesized from (Ph₃P)₃RhCl or (Ph₂MeP)₃RhCl andnido-7,8-C₂B₉H_12−n F _n ⁻ (n=1, 2, 4) salts. Hydridorhodacarboranes 3,3-(Ph₂MeP)₂-3-H-3,1,2-RhC₂B₉H_11−n F _n readily exchange the H atom at the Rh atom for the Cl atom under the action of CH₂Cl₂ to give 3,3-(Ph₂MeP)₂-3-Cl-3,1,2-RhC₂B₉H_11−n F _n . The structures of the 3,3-(Ph₃P)₂-3-H-3,1,2-RhC₂B₉H₇F₄ and 3,3-(Ph₂MeP)₂-3-Cl-3,1,2-RhC₂B₉H₉F₂ complexes were determined by X-ray diffraction analysis. Catalytic properties of the rhodacarbonanes obtained in hydrosilylation of styrene and phenylacetylene by PhMe₂SiH were studied. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 570–578, March, 1997.     

Facile formation of exo-nido→closo-rearrangement products upon the replacement of PPh3 ligands with bis(diphenylphosphino)alkanes in “three-bridge” ruthenacarborane 5,6,10-[RuCl(PPh3)2]-5,6,10-(μ-H)3-10-H-exo-nido-7,8-C2B9H8

The replacement of the PPh₃ ligands in “three-bridge” exo-nido-ruthenacarborane 5,6,10-[RuCl(PPh₃)₂]-5,6,10-(μ-H)₃-10-H-exo-nido-7,8-C₂B₉H₈ with diphosphines, viz., 1,3-bis(diphenylphosphino)propane (dppp) or 1,4-bis(diphenylphosphino)butane (dppb) dramatically decreases the barrier to the thermal exo-nido→closo rearrangement affording the chelate closo-complexes 3,3-[Ph₂P(CH₂)_nPPh₂]-3-H-3-Cl-closo-3,1,2-RuC₂B₉H₁₁ (n = 3 or 4) under mild conditions. In the reaction with dppp, the rearrangement is accompanied by the formation of 17-electron paramagnetic closo-ruthenacarborane 3,3-[Ph₂P(CH₂)₃PPh₂]-3-Cl-closo-3,1,2-RuC₂B₉H₁₁, which could be isolated as the main product when the reaction was carried out at 80 °C. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2455–2459, November, 2005.     

Synthesis and Electrochemical Behavior of Some 1H-3-Methyl-4-ethoxycarbonyl-5-(benzylidenehydrazino)pyrazoles

Summary. 1H-3-Methyl-4-ethoxycarbonyl-5-(benzylidenehydrazino)pyrazoles are key intermediates in obtaining various heterocyclic systems including pyrazolotriazoles. We present the voltammetric behavior of these compounds in nonaqueous media, with the following para substituents grafted on the benzene ring: –N(CH₃)₂, –OH, –OCH₃, –F, –Cl, –CF₃, –NO₂, as well as of the novel compounds with –Br, –I, and –SCH₃ in the para position, in order to elucidate the influence of the various substituents on the mechanism of anodic oxidation.     

New N-nitrosoamines. 1. Synthesis and nitrosative cleavage of the Mannich bases derived from nitrogen-containing heterocycles and primary aliphatic amines

The reactions of isatin, benzotriazole, and succinimide with formaldehyde and methylamine yield monoamines RCH₂N(Me)CH₂R and methylenediamines RCH₂N(Me)CH₂N(Me)CH₂R. The use of ethylenediamine as the amino component affords N,N"-disubstituted imidazolidines, while the reactions with 3-aminopropan-1-ol give N-substituted tetrahydro-1,3-oxazines. RCH₂NBuⁱ ₂ was obtained from succinimide, formaldehyde, and diisobutylamine. Nitrosative cleavage of the amines obtained was studied; it was shown that monoamines and methylenediamines give N-nitrosoamines RCH₂N(NO)Me, which were structurally characterized by X-ray diffraction analysis. RCH₂NBuⁱ ₂ affords diisobutylnitrosamine, while imidazolidines transform into dinitroso compounds RCH₂N(NO)CH₂CH₂N(NO)CH₂R.     

Reaction of γ-benzylideneaminopropanol with dialkyl phosphorochloridites

Reactions of dialkyl phosphorochloridites with 3-(N-benzylideneamino)propan-1-ol follow two pathways giving rise to linear dialkyl 1-(3-chloropropylamino)benzylphosphonates and diastereomeric cyclic 2-alkoxy-2-oxo-3-phenyl-1,4,2-oxazaphosphepanes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1453–1455, June, 2005.     

Electrooxidative coupling of salts of nitro compounds with halide,nitrite, cyanide,and phenylsulfinate anions

Electrolysis of salts of primary and secondary nitro compounds (nitroethane, 1- and 2-nitropropanes, nitrocyclohexane, and nitrocycloheptane) in the presence of excess halide, nitrite, cyanide, and phenylsulfinate anions under undivided and divided amperostatic electrolysis conditions in a two-phase medium (CH₂Cl₂/H₂O) produces geminal nitrohalides (35–85% yields), dinitro compounds (15–51%), nitronitriles (6–27%), and nitrosulfones (50–70%). The salts of secondary nitro compounds form the products of oxidative coupling with halide and phenylsulfinate anions under the undivided electrolysis conditions. In all other cases, divided electrolysis is required. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1539–1546, July, 2005.     

Intramolecular cyclization ofN-acetyl-6-(cyclopent-1-enyl)-2-methylaniline

N-Acetyl-6-(cyclopent-1-enyl)-2-methylaniline underwent intramolecular cyclization in the presence of HCl in CH₂Cl₂ at 20°C to form 2,8-dimethylspiro[cyclopentane-1,4′-4′H-3,1-benzooxazine] in quantitative yield. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 398–400, February, 1999.     

Carbofunctional fluorine-containing triethoxysilanes: synthesis,film forming and properties

Novel fluorine-containing carbofunctional organosilicon monomers were synthesized: 3-pentafluorobenzylideneaminopropylethoxysilane (EtO)₃Si(CH₂)₃N=CH-C₆F₅, N-3-methoxydiethoxysilylpropyltrifluoroacetamide (EtO)₂(MeO)Si(CH₂)₃NHC(O)CF₃, and 1,1,5-trihydrooctafluoroamyl N-3-triethoxysilylpropylaminopropanoate (EtO)₃Si(CH₂)₃NH(CH₂)₂C(O)OCH₂(CF₂)₃CHF₂. Compositions for the formation of transparent thermally stable films were prepared from these monomers. The films have low absorbance intensity near 1550 nm, i.e., in the region of photosignal transmission of modern optical communication systems. The compositions can dissolve complexes with organofluorine ligands and produce transparent homogeneous films doped with rare-earth metals. The concentrations of the complexes in the matrices are 3.7–21.4 wt.% (metal concentrations are 0.6–3.7%). Fluorescence and fluorescence excitation spectra of the matrices and electronic absorption spectra of the doped films were studied. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1131–1138, May, 2005.     

Stereospecific synthesis of 11E-tetradecenal, 11E-tetradecen-1-ol, and its acetate, pheromone components of insects ofLepidoptera order, from 10-undecenoic acid

A regio- and stereospecific synthesis of 11E-tetradecen-1-ol and its derivatives, which are pheromone components of many insect species ofLepidoptera order, by means of a reaction of methylmagnesium cuprate reagent with 1,12-tridecadien-3-yl acetate by theS _N2′ mechanism, was carried out. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1074–1075, May, 1997.     

Synthesis, Characterization of Mixed Ligand Palladium(II) Complexes of Triphenylphosphine and Anilines and their Enzyme Inhibition Studies against β-glucuronidase. The Crystal Structure of trans-dichloro-(m-chloroaniline)(triphenylphosphine)palladium(II)

A number of palladium(II) complexes with Ph₃P and aromatic amines as ligands having the general formula [(Ph₃P)Pd(Ph₃P)(NH₂R)Cl₂] {where R = Ph (1), m-ClC₆H₄ (2), p-ClC₆H₅ (3)} and [Pd(CH₃NHPh)Cl₂] (4), have been synthesized and characterized by elemental analysis, IR, ¹H and ¹³C NMR. The X-ray crystal structure of [(Ph₃P)Pd(m-ClC₆H₄NH₂)Cl₂] · CH₂ Cl₂ (2) shows a distorted square planar environment around the Pd(II) ion with the P–Pd–N and Cl(1)–Pd–Cl(2) bond angles of 174.88(5)° and 176.77(2)° respectively. The complexes were screened for enzyme inhibition activity against β-glucuronidase and found to be active.     

1-(1-Adamantyl)diaziridine

The reaction of 1-aminoadamantane with CH₂O and H₂NOSO₃H in the presence of K₂CO₃ under phase-transfer conditions leads to hitherto unknown 1-(1-adamantyl)diaziridine and (1-adamantyl)aminoacetonitrile, characterized by spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 861–862, April, 1997.     

Complexes of (ω-diphenylphosphinoalkyl)diphenylphosphine sulfides with silver nitrate in pyridine

The behavior of the phosphine-phosphine sulfide complexes of silver, [Ph₂P(S)(CH₂) _n PPh₂] _m ·AgNO₃ (n=2 or 4;m=1 or 2), in pyridine was studied. Dissolution of the 1:1 complexes in pyridine leads to destruction of their dimeric structures Ag₂[Ph₂P(S)(CH₂) _n PPh₂]₂(NO₃)₂ (A) to form the complexes Agp_y ⁺−P(Ph₂)(CH₂) _n Ph₂P=S and Agp_y ⁺−S=PPh₂(CH₂) _n PPh₂. The solid complexes isolated from pyridine restore dimeric structure A. According to the data of X-ray diffraction analysis, the 1:2 complex isolated from pyridine has the structure [S=P(Ph₂)(CH₂)₂(Ph₂)P−(NO₃)Ag(Py)−P(Ph₂) (CH₂)₂(Ph₂)P=S]Py. According to the data of IR spectroscopy, dissolution of this complex in chloroform leads to the formation of the dimeric structure Ag₂Ph₂P(S)(CH₂)₂PPh₂]₄(NO₃)₂. Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1751–1758, September, 1998.     

Contributions of hydrocarbon radicals and functional groups of organic molecules to enthalpies of their solvation in mixed water—tert-butyl alcohol solvents

The contributions of hydrocarbon radicals (−CH₃, >CH₂, >CH−, >C<) and functional groups (−OH, −OCOO−, −NO₂, −CN, >SO) to the enthalpies of solvation of organic molecules in mixed water—tert-butyl alcohol solvents were calculated in the whole range of compositions at 298.15 K. The influence of the composition and properties of the mixture on the solvation of different functional groups is discussed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1811–1814, October, 1997.     

Interaction of decacarbonyldimanganese and decacarbonyldirhenium with 1-aryl-3-cyanoprop-2-en-1-ones

The reactions of M₂(CO)₁₀ (M = Mn, Re) withtrans-1-aryl-3-cyanoprop-2-en-1-ones in the presence of Me₃NO proceed with replacement of the CO ligand and lead to complexeseq-(1-aryl-3-cyanoprop-2-en-1-on)nonacarbonyldimanganese andeq-(1-aryl-3-cyanoprop-2-en-1-on)nonacarbonyldirhenium complexes where the metals are bonded with the ligand through the nitrogen atom of the cyanogroup. The treatment of (1-phenyl-3-cyanoprop-2-en-1-on)nonacarbonyldirhenium with a second equivalent of the ligand resulted in the disubstituted complex,eq,eq-bis(1-phenyl-3-cyanoprop-2-en-1-on)octacarbonyldirhenium in a good yield. The structures of the obtained complexes are discussed on the basis of¹³C,¹H NMR, and IR-spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1485–1487, August, 1994.This work was supported in part by the Russian Foundation for Basic Research (grant No 93-03-4028).     

Cr,Co, and Mn arene π-complexes based on diphenyl- and triphenylmethane

The interaction of Ph₂CH₂ and Ph₃CH with Cr(CO)₆, Co₂(CO)₈, and Mn(CO)₅BF₄ leads to mononuclear LCr(CO)₃, LCo₄(CO)₉, and [LMn(CO)₃]BF₄ π-arene complexes. Similarly, LCr(CO)₃Co₄(CO)₉ and [LCr(CO)₃Mn(CO)₃]BF₄ heteroaromatic derivatives are obtained from LCr(CO)₃ complexes, whereas LCo₄(CO)₉ complexes afford L[Co₄(CO)₉]₂ bicluster derivatives. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1809–1812, October, 1993.     

An ionic liquid as reaction medium for the synthesis of halo-containing β-enaminones at room temperature

A series of twenty halomethylated β-enaminones [RC(O)CH=C(R ¹)NR ³ R ⁴, where R = CF₃,CCl₃, CHCl₂; R ¹ = H, Me, Ph; R ³ = H, Me, Bu, Et; R ⁴ = Me, Et, Bu, allyl, tert-amyl, CH₂CH₂OH, Bn, Ph] were synthesized using the ionic liquid [bmim]BF₄ at room temperature. It is demonstrated that this ionic liquid is a reaction medium suitable for the amination of β-alkoxyvinyl halomethyl ketones. The advantages of this method are the absence of solvents, short reaction times, and good yields. Correspondence: Marcos A. P. Martins, Núcleo de Química de Heterociclos – NUQUIMHE, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.     

Conformational study of a strained tolanophane by dynamic 1H NMR spectroscopy and computational methods

The existence of a short C–H ⋯ π (alkyl–alkyne) interaction in the structure of a strained and relatively rigid tolanophane is expected to hinder the rotation about the C–C sp³ single bond. Variable-temperature NMR experiments (performed in three solvents, CDCl₃, THF-d₈, and acetone-d₆) and ab initio density functional calculations were carried out to investigate its dynamic nature. An energy barrier of 48.6 kJ/mol is determined at coalescence (210 K) with acetone-d₆ which is in good agreement with calculation result (54 kJ/mol). Correspondence: Hossein Reza Darabi, Chemistry and Chemical Engineering Research Center of Iran, Pajoohesh Blvd., km 17, Karaj Hwy, 14968-13151 Tehran, Iran.     

4-Phosphoranylidene-5(4H)-oxazolones — A novel synthesis and properties

Summary 4-Phosphoranylidene-5(4H)-oxazolones (2), a hardly known class of phosphorus ylides, were readily prepared from 4-unsubstituted-5-(4H)-oxazolones (1) by treatment with Ph₃P-Br₂, Bu₃P-Br₂, Ph₃P-CCl₄, or Ph₃P-CBr₄ adducts in the presence of triethylamine in CH₂Cl₂ at room temperature in a novel, efficient one-pot procedure. The spectroscopic properties of the ylides are reported and discussed.

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4-Phosphoranyliden-5(4H)-oxazolone — Eine neue Synthese und Eigenschaften

Zusammenfassung 4-Phosphoranyliden-5(4H)-oxazolone, eine sehr wenig bekannte Gruppe der Phosphor-ylide, wurden auf einfache Weise nach einem neuen Eintopfverfahren mit guten Ausbeuten hergestellt. Als Ausgangsverbindungen wurden 4-unsubtituierte-5-(4H)-Oxazolone (1) eingesetzt, die unter der Einwirkung von Addukten wie Ph₃P-Br₂, Bu₃P-Br₂, Ph₃P-CCl₄ oder Ph₃P-CBr₄ in Anwesenheit von Triethylamin in CH₂Cl₂ bei Zimmertemperatur die Titelverbindungen liefern. Die spektroskopischen Eigenschaften der Ylide werden berichtet und diskutiert.