Showing papers on "Tetrahydrofuran published in 1980"
TL;DR: In this article, R1COR2 was treated with a suspension prepared from diiodomethane, trimethylaluminum and excess zinc in tetrahydrofuran at room temperature.
Abstract: Treatment of R1COR2 with a suspension prepared from diiodomethane, trimethylaluminum and excess zinc in tetrahydrofuran at room temperature affords olefins R1R2C=CH2 in fair (R1,R2=alkyl) to good (R1=alkyl, R2=H) yields. The ketone methylenation is better carried with another system consisting of CH2Br2–Zn–TiCl4. Ketones and aldehydes are transformed into α-chloro α,β-unsaturated esters or α,β-unsaturated esters in good yields on treatment with methyl trichloroacetate or t-butyl dichloroacetate (ethyl dibromoacetate) in the presence of diethylaluminum chloride and zinc.
119 citations
TL;DR: In this paper, the ortho-lithiation of 2, 3, and 4-halopyridines was achieved with lithium diisopropylamide (−78°, tetrahydrofuran) to achieve good yield.
108 citations
TL;DR: In this paper, Triphenylmethyl methacrylate (TrMA) was polymerized with two types of asymmetric anionic catalyst, lithium (R)-N-(1-phenylethyl)anilide (LiAn) and (-)-sparteine-butyllithium complex (Sp-BuLi), at −78°C.
Abstract: Triphenylmethyl methacrylate (TrMA) was polymerized with two types of asymmetric anionic catalyst, lithium (R)-N-(1-phenylethyl)anilide (LiAn) and (-)-sparteine–butyllithium complex (Sp–BuLi), at −78°C. Both catalysts yielded optically active polymers. The polymers obtained with LiAn in toluene and tetrahydrofuran (THF) showed specific rotations [α] of from −50° to −90° (in THF). The [α] of the polymer obtained with Sp–BuLi in toluene was positive and increased with polymer yield reaching above +300°s, whereas the polymer obtained in THF showed a low [α] (ca. +7°). Gel permeation chromatograms of both polymers obtained with LiAn and Sp–BuLi in THF exhibited rather narrow molecular weight distributions, whereas those obtained in toluene showed at least two or three components with markedly different molecular weights. The circular dichroism (CD) spectrum of the polymer obtained with Sp–BuLi showed strong positive peaks at 208 and 232 nm and a weak band at 250–280 nm; the polymer produced with LiAn showed a similar spectrum with opposite sign. The poly(methyl methacrylate)s derived from these poly(TrMA)s were highly isotactic but showed negligible rotations ([α] ± 2° in toluene). The polymer of high molecular weight showed clear polarization under a polarizing microscope and the low polymer obtained with LiAn appeared to show flow birefringence in chloroform at room temperature.
84 citations
TL;DR: Substituted allenes are selectively obtained in good yields from the reaction of Grignard reagents with propargylic or allenic halides in the presence of catalytic amounts of palladium chloride, triphenylphosphine and diisobutyl aluminum hydride, in tetrahydrofuran at room temperature as discussed by the authors.
61 citations
Patent•
08 Aug 1980
TL;DR: In this article, the authors proposed a room temperature-curable fluorine-containing copolymer, which can be used in heat hardening type baking enamels, two-component paints and paint bases.
Abstract: PURPOSE: A copolymer capable of curing at room temperature into films having excellent physical properties, comprising, as essential components, a fluoroolefin, cyclohexyl vinyl ether, an alkyl vinyl ether and a hydroxyalkyl vinyl ether. CONSTITUTION: A room temperature-curable fluorine-containing copolymer:consisting essentially of a fluoroolefin, e.g., tetrafluoroethylene, cyclohexyl vinyl ether, an alkyl vinyl ether, e.g., one having a 2W8C alkyl, and a hydroxyalkyl vinyl ether, e.g., hydroxybutyl vinyl ether: having the contents of the units derived from these essential monomers and other comonomer units, of 40W60mol%, 5W45mol%, 5W45mol%, 3W15mol% and 0W30mol%, respectively: and having an intrinsic viscosity measured on an uncured sample at 30°C in tetrahydrofuran, of 0.1W 2.0dl/g. This copolymer can be used in heat hardening type baking enamels, two- component paints and paint bases. COPYRIGHT: (C)1982,JPO&Japio
55 citations
TL;DR: The orange (GeII) or maroon (SnII) bivalent group 4 metal di-t-butylamides were obtained from LiNBut2 and GeCl2·dioxan or SnCl2in tetrahydrofuran, and are low melting diamagnetic, volatile, monomeric (cryoscopy in C6H12), labile compounds (readily yielding NBut2); X-ray analysis of the title compound to R= 0·091 shows that this related GeII amide is a monomer in the crystal with
Abstract: The orange (GeII) or maroon (SnII) bivalent group 4 metal di-t-butylamides were obtained from LiNBut2 and GeCl2·dioxan or SnCl2in tetrahydrofuran, and are low melting diamagnetic, volatile, monomeric (cryoscopy in C6H12), labile compounds (readily yielding·NBut2); X-ray analysis of the title compound to R= 0·091 shows that this related GeII amide is a monomer in the crystal with a long Ge–N bond of 1·885A and an NGeN angle of 111·4(5)°.
50 citations
TL;DR: In this article, two chiral derivatization reagents, D- and L-1-aminoethyl-4-dimethyl-aminonaphthalene, were synthesized from 1-dimethylaminonaphthene.
42 citations
TL;DR: In this paper, the di-lithium derivative of 1,2-diethynyl-benzene was treated with o-xylene-α,α′-diol di-p-toluenesulphonate in tetrahydrofuran.
42 citations
TL;DR: In this paper, improved synthetic procedures for ReOCl4, ReO3Cl, ReOMe4, Li2[ReMe8], and ReMe6 are described.
Abstract: Much improved synthetic procedures for ReOCl4, ReO3Cl, ReOMe4, Li2[ReMe8], and ReMe6 are described. Interaction of ReOCl4 with methanol in the presence of amine gives the unusual alkoxo-compound (MeO)2 ORe(µ-O)(µ-OMe)2 ReO(OMe)2, (A), while LiOBut gives ReO(OBut)4, and LiOPri gives an unusual dimeric species {Li[ReO(OPri)5]. LiCl(thf)2}2, (B)(thf = tetrahydrofuran. The interaction with phenol in the presence of trimethylphosphine leads to the compound trans-Re(OPh))4(PMe3)2, (C), while with lithium bis (trimethylsilyl)-amide a unique four-co-ordinate rhenium(V) compound, ReO{N(SiMe3)2}3, is obtained. The crystal and molecular structures of (A)–(C) have been determined by X-ray crystallography. Compound (A) is monoclinic, space group P21/n, a= 12.142(1), b= 15.369(1), c= 7.311(1)A, β= 90.22(1)°, and Z= 4. Compound (B) is triclinic, space group P1, a= 14.602(5), b= 13.363(3), c= 9.244(6)A, α= 98.39(4), β= 102.35(5), γ= 68.71(2)°, and Z= 1. Compound (C) is monoclinic, space group P21/c, a= 10.079(2), b= 10.527(3),c= 14.443(3)A, β= 97.28(2)°, and Z= 2. The structures have been refined to R values of 0.059 (A), 0.069 (B)′ and 0.055 (C) using respectively 1 965, 4 061, and 1 797 observed intensities, measured on a diffractometer.
40 citations
TL;DR: In this article, δ-Chloroketones and 5-oxo-9decenoic acid methyl ester were obtained from 5-chlorovaleryl chloride and methyl 4-(chloroformyl)-butyrate via Grignard reaction in tetrahydrofuran at −70°.
39 citations
TL;DR: In this article, the stereospecific photocycloaddition of 1-cyanonaphthalene to indene occured in cyclohexane, benzene, diethyl ether, tetrahydrofuran, and ethyl acetate, giving the endo head-to-head cycloadduct as the sole 1:1-adduct.
Abstract: The stereospecific photocycloaddition of 1-cyanonaphthalene to indene occured in cyclohexane, benzene, diethyl ether, tetrahydrofuran, and ethyl acetate, giving the endo head-to-head cycloadduct as the sole 1:1-adduct. The mechanism was discussed in terms of the exciplex intermediacy. In methanol or in acetonitrile in the presence of water, the photoreaction gave the dihydrocycloadduct (8), accompanied by the formation of 2-methoxyindan and 2,2′-dimethoxy-1,1′-biindanyl or 2-indanol and 1-hydroxy-2,2′-biindanyl. In these solvents, the reactions were suggested to be initiated by photochemical electron transfer; the methoxylated or hydroxylated compounds are formed by the nucleophilic attack of methanol or water on the indene cation. Anionic species, including the 1-cyanonaphthalene anion, were suggested to play important roles in the formation of 8.
Patent•
19 Nov 1980TL;DR: In this article, the oligomeric cyclic ether content of a tetrahydrofuran, an alkylene oxide-or a tetrahedronal/alkylene oxide polymerizate can be reduced by bringing the polymerization into contact with a gas in the supercritical state.
Abstract: The oligomeric cyclic ether content of a tetrahydrofuran-, an alkylene oxide- or a tetrahydrofuran/alkylene oxide polymerizate can be reduced by bringing the polymerizate into contact with a gas in the supercritical state.
TL;DR: The reaction of TeCl4 with 2,6-diacetylpyridine in methylene chloride or tetrahydrofuran gives a new type of organotellurium (IV) compound.
TL;DR: In this paper, the IR, Raman, 1 H, 13 C and 27 Al NMR spectra are discussed for tetrahydrofuran/benzene or diethyl ether in the presence of mercury.
TL;DR: The first reported conversion of metal-coordinated dinitrogen into ammonia in which the fate of the metal has been determined was reported in this paper, where ammonium bromide was detected by infrared spectroscopy among the reaction products after solvent and excess HBr had been removed in vacuo.
Abstract: This is the first reported conversion of metal-coordinated dinitrogen into ammonia in which the fate of the metal has been determined. This reaction is shown in the following equation, where triphos = PhP(CH/sub 2/CH/sub 2/PPh/sub 2/)/sub 2/ and L = PPh/sub 3/:2Mo(N/sub 2/)/sub 2/(triphos)(L) + 8HBr ..-->.. 2NH/sub 4/Br + 2MoBr/sub 3/(triphos) + 3N/sub 2/ + 2L. The metal complex which is a new subclass of bis(dinitrogen) complexes of molybdenum, reacted in tetrahydrofuran (THF) solution with anhydrous hydrogen bromide to produce ammonium bromide. No hydrazine or hydrazinium bromide was detected among the reaction products. Ammonium bromide was detected by infrared spectroscopy among the reaction products after solvent and excess HBr had been removed in vacuo. The yield of ammonia was determined quantitatively by the indophenol method after either aqueous, nonaqueous (ethanol), or two-phase (dichloromethane-water) extraction of ammonium bromide from the residue. The molybdenum-containing product slowly decomposed during the dichloromethane-water extraction step. Isolation of pure MoBr/sub 3/(triphos) was carried out in a separate experiment in which only N/sub 2/ evolution was measured. All volatiles were removed from the reaction vessel and the resulting yellow solid was washed with ethanol and dried. Its identity was confirmed by elemental analysis.
TL;DR: A series of thiocarbonyl compounds including xanthates, thioesters, thioureas, and thiones have been converted into their oxo-analogues by treatment with benzeneseleninic anhydride in tetrahydrofuran at room temperature as mentioned in this paper.
Abstract: A series of thiocarbonyl compounds including xanthates, thioesters, thioureas, thiocarbonates, and thiones have been converted into their oxo-analogues by treatment with benzeneseleninic anhydride in tetrahydrofuran at room temperature. Except for readily enolised thiones where further oxidation can take place, the method works well and compares favourably with other literature procedures. One example of a selenocarbonyl ester was likewise converted efficiently into the corresponding ester.
TL;DR: In this paper, organolithium reagents were added to p-benzoquinones in ether to obtain 4-alkyl-4-hydroxycyclohexa-2,5-dien-1-ones.
TL;DR: In this article, it was shown that a small amount of perchlorate-coordinated ligands are readily displaced in solution by any of the solvent ligands, and the bis(acetone) complex is very sensitive to moisture yielding [Pd(dppe)(OH2)2][ClO4]2 on exposure to air.
Abstract: Treatment of [Pd(dppe)Cl2], dppe = Ph2PCH2CH2PPh2, with 2 equivalents of a silver(I) salt in the presence of a solvent ligand (solvent) leads to the formation of [Pd(dppe)(solvent)2]Y2 where Y = ClO4 or BF4 In this way stable complexes with solvent = pyridine, O-bonded dimethyl sulphoxide, dimethylformamide, benzonitrile, o-toluonitrile, acetone, or water as well as (solvent)2= 1,6-dicyanohexane or o-phthalonitrile have been isolated and characterised Complexes with solvent = methanol, ethanol, acetonitrile, or tetrahydrofuran are stable in solution; on attempted isolation the ethanol complex deposits palladium metal, the methanol and tetrahydrofuran perchlorate complexes yield the bis(perchlorato)-complexes [Pd(dppe)(OClO3)2], and the acetonitrile complex yields mainly [Pd(dppe)(NCMe)2][ClO4]2 with a small amount of perchlorate-co-ordinated complex The co-ordinated perchlorate ligands are readily displaced in solution by any of the solvent ligands; the bis(acetone) complex is very sensitive to moisture yielding [Pd(dppe)(OH2)2][ClO4]2 on exposure to air Attempts to displace acetone from [Pd(dppe)(OCMe2)2]2+ and perchlorate from [Pd(dppe)(OClO3)2] by carbon monoxide failed The solvent molecules dichloromethane and benzene do not form palladium(II) complexes of the present type; treatment of [Pd(dppe)Cl2] with 2 equivalents of silver(I) perchlorate in dichloromethane–benzene yields [Pd(dppe)(OClO3)2] Preliminary investigation of the catalytic abilities of these palladium(II) complexes has shown that [Pd(dppe)(OCMe2)2][ClO4]2 catalyses the hydrogenation of styrene to ethylbenzene at atmospheric pressure and 30 °C, which is remarkably high activity for palladium(II)
TL;DR: In this paper, a novel macrocyclic compound containing two aza-bridged 2,2′-bipyridine moieties was prepared by the templated reaction of 6,6′-dichloro-2,2, 2.
Abstract: A novel macrocyclic compound containing two aza-bridged 2,2′-bipyridine moieties was prepared by the templated reaction of 6,6′-dichloro-2,2′-bipyridine. Spectroscopic investigation shows that the aza-bridging atoms form an amine ⇌; imine tautomeric system. The tautomerism is dependent upon the solvent; the imine form is preferred in non-polar solvents such as chloroform and benzene, while the amine form is favoured almost exclusively in polar solvents such as water, alcohol, acetonitrile, dimethyl sulphoxide, or tetrahydrofuran.
TL;DR: In this article, the tetrafluoborates of the primary, secondary, and tertiary ferrocenylmethyl carbenium ions have been prepared from the corresponding carbinols in ethyl ether, tetrahydrofuran and t-butyl methyl ether by adding HBF 4.
TL;DR: In this article, the reaction of iodide with [Os8(CO)23] in tetrahydrofuran yields a dark red solid which has been shown by a crystal structure analysis to be [(Ph3P)2N]2[Os8 (CO)22]], with the Os atoms in the dianion defining a bicapped octahedron.
Abstract: Reaction of iodide with [Os8(CO)23] in tetrahydrofuran yields a dark red solid which has been shown by a crystal structure analysis to be [(Ph3P)2N]2[Os8(CO)22], with the Os atoms in the dianion defining a bicapped octahedron.
TL;DR: In this paper, the proposed structures of the new compounds, with tetrahedrally coordinated central atoms and strong covalent metal-carbon interactions, are supported by mass, IR and1H,7Li,11B,13C, and31P NMR spectra.
Abstract: Dehydrohalogenation and metallation of boranato-bis-trimethylphosphonium salts (1), using two equivalents of a lithiumalkyl in tetrahydrofuran, leads to a solvated organolithium reagent H2B[(CH3)2PCH2]2Li (3) which can be converted into a 1:1n1-complex with tetramethylethylenediamin (4).3 reacts with anhydrous metal(II) halides to form spirocyclic coordination compounds of the type H2B[(CH3)2PCH2]2M[CH2P(CH3)2]2BH2 (5–9,M=Be, Mg, Zn, Cd, Hg). The reaction of [(CH3)3PBH2P(CH3)3]Br (1) with lithium tetramethylmetalates Li[M(CH3)4],M=Al, Ga, on heating in the absence of a solvent affords the metallocycles H2B[(CH3)2PCH2]2M(CH3)2 (10, 11) with evolution of methane. The products can be sublimed from the reaction mixture. The proposed structures of the new compounds, with tetrahedrally coordinated central atoms and strong covalent metal-carbon interactions, are supported by mass, IR and1H,7Li,11B,13C, and31P NMR spectra. Compound9 represents a rare case of a tetracoordinate organomercurial, compound5 is the first nonionic tetraalkylberyllate.
Patent•
21 Nov 1980
TL;DR: In this article, a conjugated diene is added to the reaction system and polymerized to obtain a titled copolymer with improved rolluing friction resistance and breaking characteristics, by copolyming styrene with butadiene in the presence of an organic Li compound.
Abstract: PURPOSE: To prepare the titled copolymer having improved rolluing friction resistance and breaking characteristics, by copolymerizing styrene with butadiene in the presence of an organic Li compound, and then carrying out the polymerization adding a conjugated diene to the copolymer just before the coupling reaction with a specific tin compound. CONSTITUTION: Styrene and 1,3-butadiene are copolymerized in a hydrocarbon solvent such as cyclohexane, in the presence of an ether compound (e.g. tetrahydrofuran) or a tertamine using 0.2W20m-mole of an organic Li compound (e.g. n-butyl Li) per 100g of the monomers. After the copolymerization, 0.5W200mol, based on 1mol of the organic Li compound, of a conjugated diene (e.g. isoprene) is added to the reaction system and polymerized. The product is incorporated with a tin compound of formulaIor II (R is alkyl, etc.; Z is halogen, X and a are 0W2; n is 1W10; y is 2W4; b is 1W3), e.g. CH 3 SnCl 3 , and subjected to the coupling reaction to obtain the objective copolymer. The amount of halogen atom of the tin compound is 0.1W3 equivalent per 1 atom equivalent of Li. COPYRIGHT: (C)1982,JPO&Japio
TL;DR: In this article, the polymerization with octylpotassium in tetrahydrofuran was found to be the most suitable for the formation of the heterotactic polymers.
Abstract: Polymerizations of various methacrylates and α-(p-substituted phenyl)acrylates were studied in toluene and tetrahydrofuran by several anionic initiators. The polymerization with octylpotassium in tetrahydrofuran was found to be the most suitable for the formation of the heterotactic polymer, defined as the polymer containing more than 50% heterotactic triads. Methacrylic acid esters of the primary alcohol gave the heterotactic polymers, whose heterotactic contents increased with an increase in the bulkiness of the ester group. Methacrylic esters of secondary alcohol generally gave heterotactic polymers with octylpotassium in tetrahydrofuran. In the polymerizations of methacrylic acid esters of tertiary alcohol, the heterotactic contents decreased with an increase in the bulkiness of the ester group. A perfectly atactic polymer was obtained in the polymerization of methyl α-phenylacrylate with butyllithium in tetrahydrofuran, but it gave the heterotactic polymer when initiated with octylpotassium in tetrahydrofuran. Methyl α-p-chlorophenylacrylate produced the heterotactic polymer in tetrahydrofuran with butyllithium as well as with octylpotassium. In the case of methyl α-p-bromophenylacrylate, the heterotactic polymer was obtained even in the polymerization in toluene with butyllithium. These results indicate that the acrylic acid ester having the bulkier substituent tends to give the heterotactic polymer more easily by anionic initiator.
TL;DR: Anhydrous lithium iodide in ether, tetrahydrofuran, or benzene is an effective reagent for the formation of αβ-unsaturated ketones by condensation of alkyl ketones with enolisable and non-enolisable aldehydes as mentioned in this paper.
Abstract: Anhydrous lithium iodide in ether, tetrahydrofuran, or benzene is an effective reagent for the formation of αβ-unsaturated ketones by condensation of alkyl ketones with enolisable and non-enolisable aldehydes; in the presence of trimethylchlorosilane–triethylamine enone formation is suppressed and high yields of 1,3-hydroxy-ketones are obtained as their trimethylsilyl ether derivatives
TL;DR: A volatile uranyl compound with a vapor pressure of 0.7 torr at 100/sup 0/C has been prepared in this paper.The compound has high thermal stability and is suitable for studies of laser-induced isotope separation.
Abstract: A volatile uranyl compound UO/sub 2/((CF/sub 3/CO)/sub 2/CH)/sub 2/.THF with a vapor pressure of 0.7 torr at 100/sup 0/C has been prepared. The compound has high thermal stability and is suitable for studies of laser-induced isotope separation. The compound has been characterized by its IR, UV, NMR, fluorescence, and mass spectra and other physical and chemical properties including an X-ray structural determination. The molecule contains a linear uranyl ion equatorially surrounded by a pentagon of oxygen atoms. The chelating anions are tilted slightly in a boatlike configuration from this plane. The crystals are monoclinic,P2/sub 1/c, with a = 8.540 (3) A, b = 9.110 (4) A, c = 28.884 (11) A, ..beta.. = 94.26 (3)/sup 0/, and Z = 4.
TL;DR: The reaction of the transition metal compounds MCl n MCL n TiCl 4 ;VCl 4, CrCl 2 or 3 ; MoOCl 3, WCl 6 and FeCl 3 with magnesium and tetrahydrofuran yields organometallic cluster compounds as discussed by the authors.
Patent•
21 Jan 1980TL;DR: A method of polymerizing cyclic ethers especially tetrahydrofuran to form high molecular weight polymers using a zeolitic polymerization catalyst was proposed by.
Abstract: A method of polymerizing cyclic ethers especially tetrahydrofuran to form high molecular weight polymers using a zeolitic polymerization catalyst.