Amidoalkylation of Tervalent Phosphorus Chlorides with N-α-Hydroxypolyhalogenoalkyl Amides

Abstract

A new preparative method for synthetically and biologically important N-acyl-, N-phosphoryl-, and N-sulfonylaminopolyhalogenoalkylphosphonyl derivatives 2 is presented.     

4,5-Dihydroxyimidazolidin-2-ones in the reaction of α-ureidoalkylation of N-(carboxyalkyl)-, N-(hydroxyalkyl)-, and N-(aminoalkyl)ureas

Russian Chemical Bulletin - It was found for the first time that the reaction of N-(carboxyalkyl)ureas (ureido acids) with 4,5-dihydroxy-1,3-dimethyl-4,5-diphenylimidazolidin-2-one in methyl or...     

Two New Amides from the Roots of Acorus Tatarinowii Schott

AcorustatarinowiiSchottiswidelydistributedinChinaItisatraditionalhefbmedcineinChinaandusedasadigestan,anexpectoranandasanimulanagainstdigttveedisorders,diarrheaandepilepsy.InordertoelucidaetheStrUctUresOfitsactiVePrinciples,weSySteInaticallyStUdiedtheroosofAconatatannowtiSchott.Asaresultofinveedgations,wenowreportthemCtUrsofbonewaInjdes,tatardrideA(1)andtatardrideB(2).COmpondlwasisolatedascolourlessoil.Icr]D-46'5lo(cO.O86,acetone).EI-MS(In/.)f28l(M+-H,o,57%),224(49%),l47(loo%),l3…     

Crystal Structure of N-(O-Ethylphenylthionophos-phonyl) N'-(O-p-iodinephenylphenylthionophos-phonyl)thiosemicarbazide

1mThODUCT'ONSomecomPOundsofN--thionophosphonylandN,N'--his(thionophosphonyl)thiOSemicarbazideshaveattractedmuchattentionandbeenextensivelystudiedinrecentyears"~'i.ThiskindofcomPOundsareknowntohaveobviousantibacterialandantifungalactivitiest3}.TherearetwochiralphosphoratomsinthecomPOundsofN,N'--his(thionophosphonyl)thiosemicarbazide.Inordertostudyfurthertherelationshipbetweenthestructureandbiologicalactivities,hereinwerePOrtthecrystalstructureofakindofN,N'--his(thionophosphonyl)thiose…     

Time-resolved photoelectron studies of the relaxation of the S1(1E′') excited state of sym-triazine

We present photoelectron spectra of the lowest singlet state (¹E′') of sym-triazine obtained with 2 ns and 5 ps excitation sources. Comparisons of picosecond and nanosecond spectra are made at three wavelengths, corresponding to the 6₀¹, 6₀² and the 6₀¹12₀¹ vibrational levels. The spectra show that rapid (</ 5 ps) relaxation to the lowest triplet state occurs subsequent to singlet excitation. Coupling of S₁ levels to the T₁ manifold is very inhomogeneous with intersystem crossing rates ranging from 10⁷ s⁻¹ to > 10¹¹ s⁻¹. Furthermore, for excitation at the 6₀¹12₀¹ level we find evidence for relaxation to another excited state at rates ⩾ 10¹¹ s⁻¹.     

Synthesis and cyclization of N-(2-hydroxyphenyl)-and N-(2-benzyloxyphenyl)-Β-alanines

N-Substituted -alanines have been synthesized by treating o-aminophenol or o-benzyloxyaniline with acrylic, methacrylic, or crotonic acids. Their cyclization to 2-benzoxazolinones and dihydro-2,4(1H,3H)-pyrimidinediones has been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 527–531, April, 1991.     

Silicon-induced diastereoselectivity of the catalyzed phosphorylation of 1-(perfluoroalkyl)-ω (trialkylsilyl)alkan-1-ols

The stereochemistry of catalytic phosphorylation of 1-(perfluoroalkyl)--(trialkylsilyl)alkan-1-ols with pentavalent phosphorus acid monochlorides (phosphonochloridates, methyl(phenyl)phosphinic chloride, and phosphorochloridates) was studied. The effects of the structures of alcohols and phosphorylating agents on the degree of the reaction diastereoselectivity were investigated. Methylphosphonochloridates were found to react most stereoselectively; the diastereoselectivity of the phosphorylation is independent of the donor or acceptor character of substituents at the phosphorus atom, being determined by their volumes. In the series of silylalkanols, the diastereoselectivity of the reaction the higher the closer the Si atom to the reactive site of the molecule, the larger the volume of the perfluoroalkyl substituent, and the more pronounced the electron-withdrawing properties of the substituents at the Si atom. A reaction mechanism is proposed that rationalizes the stereoselectivity of the reaction.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1930–1936, September, 2004.     

Studies on the Effect of Various Anions and Pyridine on the Stereochemistry of Lanthanide(III) Coordination Compounds of 4[N-(2′-Hydroxy-1′-Naphthalidene)Amino] Antipyrine Thiosemicarbazone

In the present studies, the effect of pyridine on stereochemistry of the coordination compounds of lanthanide(III) derived from 4[N-(2′-hydroxy-1′-naphthalidene)amino] antipyrine thiosemicarbazone (HNAAPTS) has been studied. The general composition of the present complexes is LnX₃·n(HNAAPTS)·Py (Ln = La, Pr, Nd, Sm, Gd, Tb, Dy, or Ho; X = NO₃, n = 1, x = Cl, NCS or ClO₄, n = 2, Py = pyridine). All the complexes were characterized by elemental analyses, molecular weight, molar conductance, magnetic susceptibilities, infrared and electronic spectral studies. The infrared studies reveal that the HNAAPTS behaves as a neutral tridentate (N, N, S), while pyridine is coordinated to metal ions via its nitrogen atom. Nitrates are bicovalently bonded, while thiocyanate is coordinated through a strong N-atom. Perchlorate ions are not coordinating in coordination sphere. From electronic spectral data, nephelauxetic effect (β), covalence factor (b^½), Sinha parameter (δ%), and the covalence angular overlap parameter (η) have been calculated. Thermal stabilities of these complexes were studied by thermogravimetric analysis. In conclusion, the coordination number of lanthanides(III) in the present compounds is either seven or ten depending on the coordinating anions.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Enzymatic α(1→2)-l-fucosylation: investigation of the specificity of the α(1→2)-l-galactosyltransferase from Helix pomatia

The α(1→2)-l-galactosyltransferase from Helix pomatia transfers an l-fucosyl residue from GDP-l-Fucose to a terminal, non-reducing d-galactopyranosyl moiety of an oligosaccharide. The extent of the enzyme's specificity towards the stereochemistry at the d-galactopyranosyl anomeric centre, the site of interglycosidic linkage and the nature of the subterminal oligosaccharide residue has been investigated using HPAEC-PAD and MALDI-TOF technology. This α(1→2)-l-galactosyltransferase is specific for d-galactopyranosyl β-linkages, independent of the site of the interglycosidic linkage and aglycone configuration and with limited specificity for the nature of the subterminal sugar residue.     

Gram scale synthesis of the C(1)–C(9) fragment of amphidinolide C

An allylic cis-epoxide prepared by Sharpless asymmetric epoxidation was transformed in nine steps and 41% overall yield to the cyclization precursor 4 via a key one carbon homologation. Cobalt-catalyzed aerobic oxidative cyclization of 4 gave the trans-THF in 94% yield at gram scale. Subsequent manipulations, including a Still–Gennari olefination, Sharpless asymmetric dihydroxylation, Corey–Fuchs alkynylation, and Kazmaier hydrostannylation provided the fully functionalized C(1)–C(9) fragment 2 suitable for cross-coupling. The sequence is readily scalable and provides gram quantities of 2.     

Stereochemistry of the asymmetric reduction of (1′s)-1,3-dimethyl-4(1′-phenylethylimino)piperidine

The stereochemistry of the asymmetric reduction of the imine obtained from 1,3-dimethylpiperidin-4-one and (S)--phenylethylamine has been studied. It is shown that hydride reduction of imine 1 by sodium borohydride in methanol is asymmetric and gives the cis and trans diastereomeric pair 1,3-dimethyl-4-(-phenyl-ethylamino) piperidine in the ratio 3:1. Using sodium in isopropanol gives only one trans diastereomeric pair.¹H NMR has been used to identify the stereochemical structure and diastereomer excess of the cis and trans isomers of 1,3-dimethyl-4-(-phenylethylamino)piperidine which had been separated by column chromatography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 219–221, February, 1996.     

Effect of trimethylaluminum on the formation of active sites of the catalytic system bis[N-(3,5-di-tert-butylsalicylidene)-2,3,5,6-tetrafluoroanilinato]titanium(IV) dichloride—MAO and catalytic isomerization of hex-1-ene

The transformations of bis[N-(3,5-di-tert-butylsalicylidene)-2,3,5,6-tetrafluoroanilinato]-titanium(iv) dichloride (L₂TiCl₂) occurring in toluene under the action of methylalumoxane (MAO) were studied by ¹H NMR spectroscopy. The commercially available MAO containing trimethylaluminum (AlMe₃) and MAO free of AlMe₃ (the so called “dry” MAO) were used. The catalytic transformations of hex-1-ene involving the systems L₂TiCl₂-MAO were studied. We proposed the structures of the cationic titanium complexes formed in the absence and in the presence of hex-1-ene under the action of MAO. In the absence of olefin, neutral and cationic titanium complexes are decomposed under the action of AlMe₃ according to the exchange reaction of the complex ligand with the methyl groups of AlMe₃ to form LAlMe₂. The neutral complexes react considerably faster than the cationic ones. In the presence of olefin, decomposition of complexes under the action of AlMe₃ is suppressed. The titanium complex activated by “dry” MAO isomerizes hex-1-ene to hex-2-ene. In the presence of large amounts of TMA (commercial MAO), this reaction does not take place.     

Structure of the Adduct of N-(α-Phenylethyl)acetamide with HCl in the Liquid,Solid, and Gas Phases

The structure of the adduct of N-(-phenylethyl)acetamide with HCl in the liquid and solid phases was examined by elemental analysis, ¹H and ¹³C NMR spectroscopy, and X-ray diffraction to show that the positive charge is localized on the nitrogen atom. The electronic structure of the adduct in the gas phase was studied by means of ab initio calculations at the 6-31G^{* *} level of theory. In the latter case, the positive charge is delocalized over the acetamide fragment of the molecule.     

Cyclization of N-(2,4,6-trimethylphenyl)-β-alanines

Reaction of 2,4,6-trimethylaniline with acrylic and itaconic acids gives the corresponding N-substituted =alanines which can be converted to derivatives of tetrahydropyridone, dihydropyrimidinedione, and 4-carboxy-2-pyrrolidinone. Bromination of the aromatic substituent in the synthesized heterocycles has been carried out.Kaunas Technological University, Kaunas 3028, Lithuania Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 951–954, July, 2000     

New approach to the synthesis of 2,6-difluorobenzoyl isocyanate and its use in the preparation of N-(2,6-difluorobenzoyl)-N′-(polyfluoroaryl)ureas

The treatment of 2,6-difluorobenzoyl chloride with trimethylsilyl isocyanate gave 2,6-difluorobenzoyl isocyanate. This product reacts with polyfluoroaromatic amines to give the corresponding N-(2,6-difluorobenzoyl)-N-(polyfluoroaryl)urea, which hold potential as inhibitors for the biosynthesis of insect chitin.Institute of Chemistry, Bashkir Science Center, Urals Branch, Russian Academy of Sciences, 450054 Ufa. Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 468–470, February, 1992.     

Reassignment of the absolute configuration of the baker's yeast reduction of (±)-ethyl 1-allyl-2-oxocyclopentanecarboxylate

The baker's yeast reduction of (±)-ethyl 1-allyl-2-oxocyclopentanecarboxylate under aqueous conditions in the presence of CuO yields (1S,2S)-(+)-ethyl 1-allyl-2-hydroxycyclopentanecarboxylate and the unreacted enantiomer (1R)-(−)-ethyl 1-allyl-2-oxocyclopentanecarboxylate. The absolute configuration of the secondary alcohol was determined from the X-ray crystal structure of the (1S)-10-camphorsulfonyl derivative of (1S,2S)-(+)-ethyl 1-allyl-2-hydroxycyclopentanecarboxylate. This refutes configurational claims based on CD/ORD and chemical affiliation techniques currently reported in the literature for this reaction.     

Studies on the crystal structure and characterization of N-(4-acetylphenyl)-N’-(2-nitrobenzoyl)-thiourea

N-(4-acetylphenyl)-N′-(2-nitrobenzoyl)-thiourea has been synthesized in high yield under PEG-400 as the phase-transfer catalyst and its the compound structure was determined by single crystal X-ray diffraction. The compound is also a considerable plant-growth regulator. In addition, the compound L exhibited selective recognition for Hg²⁺ over other metals ions such as Ag⁺, Ca²⁺, Co²⁺, Ni²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Cr³⁺, and Mg²⁺ in DMSO solutions.     

Structure and Molecular Lability of N-(Thio)phosphoryl(thio)amides: XL. Interpretation of the N-Benzoyl(acetyl)amidothiophosphate → N-Thiobenzoyl(acetyl)amidophosphate Rearrangement by means of 1H, 1 3C,and 3 1P NMR Spectroscopy

The N-benzoyl(acetyl)amidothiophosphateN-thiobenzoyl(acetyl)amidophosphate in CCl₄ and toluene-d ₈ solutions was studied by means of ¹H, ^{1 3}C, and ^{3 1}P NMR spectroscopy. The transformation of one amide form to the other is accompanied by intramolecular migrations of the amide proton and (thio)phosphoryl group and is a complex equilibrium of two dynamic systems.     

Sub-doppler two-photon spectrum of asymmetric rotor molecules: analysis of the qqQ rotational branch of the S1(1B2u)141 ← S0(1A1g) system of benzene-d1

The Doppler-free two-photon excitation spectrum of the ^qqQ branch of the 14¹₀ vibrational band of the S₁(¹B_2u) ← S₀(₁A_1g) transition of benzene-d₁ has been recorded using a cw single-mode dye laser coupled to an external concentric resonator. The spectrum has been analysed using a non-rigid Watson Hamiltonian. More than 200 lines with J up to 20 have been assigned and the rotational constants which best reproduce the spectrum are A¹_v = 0.181435, B¹_v = 0.169990, C¹_v = 0.089055 cm⁻¹. The K_a = odd lines of the ^qqQ₅(J) subbranch show small and quite regular perturbations of 60 ± 5 MHz which are probably due to a coupling to another vibrational state of the S₁ manifold.