Showing papers in "Journal of The Chemical Society, Chemical Communications in 1979"
TL;DR: The reaction of aryl halides with alk-l-enylboranes, readily obtainable via monohydroboration of acetylenes, provides a conveninet new method for stereoselective synthesis of E-alkenes in high yields; these reactions are effectively catalysed by tetrakis(triphenylphosphine)palladium and bases such as sodium ethoxide as discussed by the authors.
Abstract: The reaction of aryl halides with alk-l-enylboranes, readily obtainable via monohydroboration of acetylenes, provides a conveninet new method for stereoselective synthesis of arylated (E)-alkenes in high yields; these reactions are effectively catalysed by tetrakis(triphenylphosphine)palladium and bases such as sodium ethoxide.
940 citations
TL;DR: The electrochemical polymerization of pyrrole on platinum produces a strongly adhered, durable film with enhanced conductivity and good electrode properties as mentioned in this paper, which can be used to construct a durable film.
Abstract: The electrochemical polymerization of pyrrole on platinum produces a strongly adhered, durable film with enhanced conductivity and good electrode properties.
894 citations
TL;DR: In this paper, a flexible film of polypyrrole with p-type conductivities of 100 Ω-1 cm-1 was obtained by electrolytic oxidation of the appropriate pyrrole monomers.
Abstract: Highly stable, flexible films of polypyrrole with p-type conductivities of 100 Ω–1 cm–1 have been prepared by electrolytic oxidation of the appropriate pyrrole monomers; similarly prepared films of mixtures of pyrrole and N-methylpyrrole have conductivities between 5 × 10–3 and 100 Ω–1 cm–1 depending upon the composition.
336 citations
TL;DR: In this paper, the tetrameric structure of the low melting point product obtained from the base catalysed condensation of formaldehyde and para-t-butylphenol and its ability to form a stable cage-type clathrate with toluene was analyzed.
Abstract: Single-crystal X-ray analysis has shown the tetrameric structure of the low melting point product obtained from the base catalysed condensation of formaldehyde and para-t-butylphenol and its ability to form a stable cage-type clathrate with toluene.
234 citations
TL;DR: In this article, an analysis of Ru-N bond lengths based on an X-ray crystallographic determination of the molecular structure of [Ru(bipy)3]2+ and on reactivity patterns of various [Ru[Ru[n+]n+ species suggests that members of the series have similar structures; this similarity may be important in the development of new solar energy catalysts.
Abstract: Analysis of Ru–N bond lengths based on an X-ray crystallographic determination of the molecular structure of [Ru(bipy)3]2+ and on reactivity patterns of various [Ru(bipy)3]n+ species suggests that members of the series have similar structures; this similarity may be important in the development of new solar energy catalysts.
193 citations
TL;DR: When silvery films of the semiconducting polymer, cis-polyacetylene, (CH)x, are used as the anode in the electrolysis of aqueous KI solutions or methylene chloride solutions of [Bun4N]-[ClO4] as mentioned in this paper, they have high conductivities characteristic of the metallic state.
Abstract: When silvery films of the semiconducting polymer, cis-‘polyacetylene,’(CH)x, are used as the anode in the electrolysis of aqueous KI solutions or methylene chloride solutions of [Bun4N]+[ClO4]–, films of (CHIy)x and [CH(ClO4)y]x, respectively, are obtained which, for the compositions [CHI0·07]x and [CH(ClO4)0·0645]x have high conductivities characteristic of the metallic state.
172 citations
TL;DR: In this paper, an efficient conversion of primary and secondary hydroxy-groups into iodo-groups, with inversion, in carbohydrates was described using either triphenylphosphine, iodine, and imidazole in toluene at elevated temperature.
Abstract: Efficient conversions of primary and secondary hydroxy-groups into iodo-groups, with inversion, in carbohydrates are described using either triphenylphosphine, iodine, and imidazole or triphenylphosphine and 2,4,5-tri-iodoimidazole in toluene at elevated temperature.
169 citations
TL;DR: In this article, the reactions of alkenyl sulphides, benzenethiols, and aryl sulphides with methylmagnesium, mediated by bis(triphenylphosphine)nickel dichloride, in benzene solution have been shown to lead to olefins (predominantly with retention of configuration), toluenes, and biphenyls in medium to high yields.
Abstract: The reactions of alkenyl sulphides, benzenethiols, and aryl sulphides with methylmagnesium and arylmagnesium bromides, mediated by bis(triphenylphosphine)nickel dichloride, in benzene solution have been shown to lead to olefins (predominantly with retention of configuration), toluenes, and biphenyls in medium to high yields.
166 citations
TL;DR: On treatment with tetramethyl-α-halogenoenamines at room temperature or below, carboxylic acids are converted into acyl halides in high yields under neutral conditions as discussed by the authors.
Abstract: On treatment with tetramethyl-α-halogenoenamines at room temperature or below, carboxylic acids are converted into acyl halides in high yields under neutral conditions.
163 citations
TL;DR: Bromotrimethylsilane is highly selective for P-O silyldealkylation of mixed carboxylate-phosphonate alkyl esters and can be used to prepare trimethylsilyl amido-, alkynyl-, and iodoalkyl-ph phosphonates in good yield, thus making the corresponding phosphonic acids readily available via hydrolysis with neutral H2O.
Abstract: Bromotrimethylsilane is highly selective for P–O silyldealkylation of mixed carboxylate–phosphonate alkyl esters and can be used to prepare trimethylsilyl amido-, alkynyl-, and iodoalkyl-phosphonates in good yield, thus making the corresponding phosphonic acids readily available via hydrolysis with neutral H2O.
141 citations
TL;DR: In this paper, a general route for the synthesis of allenes from acetylenes is reported and appropriate reaction conditions are described for the preparation of substituted allenes and allenols, including optically active allenol.
Abstract: A general route for the synthesis of allenes from acetylenes is reported and appropriate reaction conditions are described for the preparation of substituted allenes and allenols, including optically active allenols
TL;DR: In this paper, trimethylsilyl iodide is used for debenzylation of O-benzyltyrosine without the formation of rearrangement products, which is useful for removing urethane and benzyl ether blocking groups.
Abstract: Removal of urethane and benzyl ether blocking groups from peptides is readily accomplished by treatment with trimethylsilyl iodide which is particularly useful for the debenzylation of O-benzyltyrosine without the formation of rearrangement products.
TL;DR: In this article, a solid superacid catalyst was obtained by exposing H4TiO4 to 1 N H2SO4 and then calcining in air at 500 °C; this catalyst was active for skeletal isomerizations of butane and isobutane.
Abstract: Solid superacid catalyst was obtained by exposing H4TiO4 to 1 N H2SO4 and then calcining in air at 500 °C; this catalyst was active for skeletal isomerizations of butane and isobutane.
TL;DR: In this article, it was shown that considerable asymmetric induction can occur in Diels-Alder reactions catalysed by chiral alkoxyaluminium dichlorides, and that it is possible to obtain a chiral dichloride-based reaction.
Abstract: Evidence is presented that considerable asymmetric induction can occur in Diels–Alder reactions catalysed by chiral alkoxyaluminium dichlorides.
TL;DR: In this paper, the title compound reacts with a number of electrophiles with a different reactivity from that of the dianion of methyl acetoacetate, which is the most common electrophilic compound.
Abstract: The title compound reacts with a number of electrophiles with a different reactivity from that of the dianion of methyl acetoacetate.
TL;DR: In this paper, a diastereoisomeric mixture of NNO2-tribenzoyladenosine 3′,5′-cyclic phosphoranilidates (4) was obtained and the absolute configuration at the P atom in (5) and (1) was established by 31P n.r.
Abstract: NNO 2
′-Tribenzoyladenosine 3′,5′-cyclic phosphate (3) was converted into a diastereoisomeric mixture of NNO2′-tribenzoyladenosine 3′,5′-cyclic phosphoranilidates (4); after separation of these diastereoisomers, the corresponding adenosine 3′,5′-cyclic phosphorothioates (1, cAMPS) were obtained and the absolute configuration at the P atom in the diastereoisomers of (4) and (1) was established by 31P n.m.r. spectroscopy.
TL;DR: The catalysts for the hydrogenation of nitriles under ambient conditions, producing primary amines selectively; they are also active for the dehydrogenation of amines at higher temperatures to give Nitriles or imines as mentioned in this paper.
Abstract: [RhH(PPri3)3] and [Rh2H2(µ-N2){P(cyclohexyl)3}4] are active catalysts for the hydrogenation of nitriles under ambient conditions, producing primary amines selectively; they are also active for the dehydrogenation of amines at higher temperatures to give nitriles or imines.
TL;DR: Palladium(0)phosphine complexes catalyse the cyclodimerisation of methylenecyclopropanes and carbon dioxide with opening of the three-membered ring to give fivemembered lactones as mentioned in this paper.
Abstract: Palladium(0)–phosphine complexes catalyse the cyclodimerisation of methylenecyclopropanes and carbon dioxide with opening of the three-membered ring to give five-membered lactones.
TL;DR: The dihydrofolate reductase catalysed reduction of the vitamin folic acid to the coenzyme 5,6,7,8-tetrahydrofolic acid involves transfer of the 4-pro-R-hydrogen of NADPH to the si-face at C-7 of folic Acid.
Abstract: The dihydrofolate reductase catalysed reduction of the vitamin folic acid (5) to the coenzyme 5,6,7,8-tetrahydrofolic acid (2) involves transfer of the 4-pro-R-hydrogen of NADPH to the si-face at C-7 of folic acid (5); the absolute stereochemistry at C-6 of 5,6,7,8-tetrahydrofolic acid (2) from the enzymic reduction has been correlated with that of biologically active folinic acid (3), and the reduction at both C-6 and C-7 therefore involves the same side of NADPH and the same face of folic acid.
TL;DR: Evidence is presented from 13C n.r.m. spectroscopic studies which indicates that the enzymic transformation of porphobilinogen into uroporphyrinogens I and III occurs through a transient free intermediate, pre-uroporphyrinogen, produced by porph Mobilinogen deaminase (uroporPHyrinogenic I synthetase).
Abstract: Evidence is presented from 13C n.m.r. spectroscopic studies which indicates that the enzymic transformation of porphobilinogen into uroporphyrinogens I and III occurs through a transient free intermediate, pre-uroporphyrinogen, produced by porphobilinogen deaminase (uroporphyrinogen I synthetase).
TL;DR: Evidence is presented which demonstrates that the deaminase and cosynthetase function independently and sequentially in the overall conversion of porphobilinogen into uroporphyrinogen III.
Abstract: Pre-uroporphyrinogen, produced from porphobilinogen by the action of porphobilinogen deaminase has been shown to act as a substrate for the enzyme uroporphyrinogen III cosynthetase, being converted in high yield into uroporphyrinogen III; in the absence of cosynthetase, pre-uroporphyrinogen rearranges chemically to afford exclusively uroporphyrinogen I, and evidence is also presented which demonstrates that the deaminase and cosynthetase function independently and sequentially in the overall conversion of porphobilinogen into uroporphyrinogen III.
TL;DR: In this article, the relative conformation of 1H and 13C n.m.r. spectroscopy and its absolute configuration was determined by the benzoate chirality method.
Abstract: 1,5-Dideoxy-1,5-imino-D-mannitol, (1), has been isolated as an unusual constituent of Lonchocarpus sericeus and L. costaricensis; its relative conformation has been determined by 1H and 13C n.m.r. spectroscopy and its absolute configuration determined by the benzoate chirality method.
TL;DR: The occurrence and stereochemistry of a rapid reversible C-H fission in this article was established by n.m.r. spectroscopy, including triple resonance INDOR, and by X-ray crystallography.
Abstract: The occurrence and stereochemistry of a rapid reversible C–H fission in [[graphic omitted]But2)] is established by n.m.r. spectroscopy, including triple resonance INDOR, and by X-ray crystallography.
TL;DR: The structure of ‘K-76’(1), a complement inhibitor containing a spirobenzofuran unit, obtained from Stachybotrys complementi nov. sp.
Abstract: The structure of ‘K-76’(1), a complement inhibitor containing a spirobenzofuran unit, obtained from Stachybotrys complementi nov. sp. K-76, is reported.
TL;DR: In this article, the labile unrearranged hydroxymethylbilane (5) is synthesised unambiguously, is proved to be identical with the product from deaminase acting on porphobilinogen, and is shown to be the substrate for deaminases-free cosynthetase which quantitatively ring-closes with rearrangement to uro'gen-III.
Abstract: The labile unrearranged hydroxymethylbilane (5) is synthesised unambiguously, is proved to be identical with the product from deaminase acting on porphobilinogen, and is shown to be the substrate for deaminase-free cosynthetase which quantitatively ring-closes (5) with rearrangement to uro'gen-III (7).
TL;DR: In this article, it was shown that bis(trimethylsilyl)acetylenes with 1-10 mol% KF-18-crown-6 ether can be obtained by quantitative monodesilylation with MeLiLiBr complex.
Abstract: Substituted acetylenic carbinols such as (2), (5), and (6) are obtained from the reaction of carbonyl compounds with the potassium or lithium salts of trimethylsilyacetylenes; these are prepared either by the in situ cleavage of bis(trimethylsilyl)acetylenes with 1–10 mol% KF–18-crown-6 ether or by the quantitative monodesilylation of bis-silylacetylenes with MeLiLiBr complex.
TL;DR: In this paper, the reaction of tetrasodium tetrathiafulvalene-tetrathiolate with transition metal salts leads to the formation of tetrathyfulvalenes-metal bisdithiolene oligomers which in the case of the nickel derivative possesses unusually high conductivity (ca. 30 Ω-1 cm-1).
Abstract: Reaction of tetrasodium tetrathiafulvalene-tetrathiolate with transition metal salts leads to the formation of tetrathiafulvalene-metal bisdithiolene oligomers which in the case of the nickel derivative possesses unusually high conductivity (ca. 30 Ω–1 cm–1).
TL;DR: The thermal decomposition of aryl diazonium salts of nonfluorinated acids in anhydrous media, generated by protonation of piperidyl triazenes, gives products resulting from reaction with added nucleophiles including high specific activity 18F-fluoride ions as mentioned in this paper.
Abstract: Thermal decomposition of aryl diazonium salts of nonfluorinated acids in anhydrous media, generated by protonation of piperidyl triazenes, gives products resulting from reaction with added nucleophiles including high specific activity 18F-fluoride ions.
TL;DR: In this article, a deep blue mixed valence complex was found to be in equilibrium with [VIVO(nta)(H2O)] and [VVO2 (nta)]2 in aqueous solution; the crystal structure of its ammonium salt trihydrate has been determined.
Abstract: A deep blue mixed valence complex [VO(nta)–O–VO(nta)]3–(nta = nitrilotriacetate) was found to be in equilibrium with [VIVO(nta)(H2O)]– and [VVO2(nta)]2– in aqueous solution; the crystal structure of its ammonium salt trihydrate has been determined.
TL;DR: The peptide pivaloyl-D-Pro-L-Pro L-Ala-N-methylamide adopts a highly folded conformation in the solid state involving a type II bend followed by a type I bend, stabilised by two intramolecular 4 \rightarrow 1 hydrogen bonds as discussed by the authors.
Abstract: The peptide, pivaloyl-D-Pro-L-Pro-L-Ala-N-methylamide adopts a highly folded conformation in the solid state involving a type II bend followed by a type I bend, stabilised by two intramolecular 4 \rightarrow 1 hydrogen bonds.