Electrolytic reduction of 2-butyne-1,4-diol as a route to trans-2-butene-1,4-diol

The effect of the cathode material on the electrochemical transformations of 2-butyne-1,4-diol at atmospheric pressure was studied by chromatographic analysis. The optimal parameters of the selective synthesis of trans-2-butene-1,4-diol were determined.     

Potentialities of the Voltammetry of 2-Butyne-1,4-diol at Mechanically Renewed Solid Electrodes

The electrochemical behavior of 2-butyne-1,4-diol was studied at solid platinum, gold, silver, cobalt, nickel, copper, and graphite electrodes. The working surfaces of the electrodes were renewed by cutting a thin 0.5-µm layer in the test solution immediately before recording every voltammogram. 2-Butyne-1,4-diol was oxidized in alkaline solutions at graphite, nickel, silver, and copper electrodes at positive potentials; the voltammograms obtained at these electrodes were suitable for analytical purposes. The dependence of the anodic current of 2-butyne-1,4-diol on its concentration was linear in the range from 0.03 to 0.3 g/L.__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 5, 2005, pp. 499–503.Original Russian Text Copyright © 2005 by Skvortsova, Aleksandrova, Kiryushov.     

Determination of 2-Butyne-1,4-Diol Dioxyethyl Ether in Nickel-Plating Electrolytes

A procedure was developed for determining 2-butyne-1,4-diol dioxyethyl ester in nickel-plating electrolytes in the presence of hydrogenation products. The difference in the bromination capacity of ethylene and acetylene bonds forms a basis for the direct potentiometric titration of ethylene hydrogenation products with potassium bromate and the back titration of excess bromate after the bromination of acetylene compounds. The relative error of determination was no worse than 4%.     

An Efficient Synthesis of 3,4-bis(Tri-n-butylstannyl)furan

Abstract

Palladium-catalysed addition of hexa-n-butylditin to 2-butyne-1,4-diol, followed by oxidative cyclisation and dehydration gives 3,4-bis(tri-n-butylstannyl)furan in high yield.     

Investigation of Electrosorption of Organic Molecules onto Gold and Nickel Electrodes Using an Electrochemical Quartz Crystal Microbalance

The adsorption behaviors of two organic molecules, benzoic acid (BA) and 2-butyne-1,4-diol (BD), on metal electrodes have been studied using an electrochemical quartz crystal microbalance (EQCM) combined with the cyclic voltammetry technique. In the range of potentials studied, BA molecules were adsorbed onto an electrodeposited gold electrode with a saturation concentration of 5.0 × 10¹⁴ molecules/cm². It was found that the Frumkin isotherm model was most suitable to depict the electrosorption behavior. The isotherm parameters by nonlinear fitting, which agreed with the literature values, implied BA was chemisorbed on the gold surface. For BD on an electrodeposited nickel electrode, the equivalent molar mass of the reaction species was calculated on the basis of the voltammetry curve and mass curve, which were obtained simultaneously during the potential scan. The analysis of EQCM data for the electrosorption of BD on gold and nickel electrodes showed an irreversible characteristic; the latter effectively inhibited the hydrogen evolution reaction.     

Functional Acetal Methacrylates: III. Electrophilic Addition of Diols to 2-(Vinyloxy)ethyl Methacrylate

Reactions of 2-(vinyloxy)ethyl methacrylate with diols [ethylene glycol, diethylene glycol, triethylene glycol, oligoethylene glycol-400, Z-2-butene-1,4-diol, 2-butyne-1,4-diol, 1,1,3,3-tetramethyl-1,3-bis(3-hydroxypropyl)disiloxane, 2,2-bis(4-hydroxyphenyl)propane] and polyols (glycerol, pentaerythritol) under electrophilic conditions (1 wt% of CF₃COOH, 20-60°C, 1-3 h) result in quantitative formation of functional acetal methacrylates.     

Studies towards the total synthesis of cruentaren A and B: Stereoselective synthesis of fragments C1-C11, C12-C22 and C23-C28

A convergent and stereoselective approach for the synthesis of C1-C11, C12-C22, and C23-C28 fragments of cytotoxic natural products cruentaren A and B are accomplished. Highlights of the strategy include a Sharpless epoxidation followed by a regioselective opening of epoxide to generate anti and syn-stereochemistry at C9-C10 and C15-C16, an Alder-Rickert reaction between a 1,5-dimethoxy-1,4-cyclohexadiene and dienophile to construct the aromatic ring, and a lithium-mediated aldol reaction to install the C17-C18 anti-stereochemistry. The synthesis of C1-C11 and C12-C22 fragments proceed with a longest linear sequence of 10 and 17 steps from commercially available 2-butyne-1,4-diol and cis-2-butene-1,4-diol respectively.     

Synthesis of 1,2-Dihydropyridines, 2,3-Dihydro-4(1H)-pyridinone,and 1,2,3,4-Tetrahydropyridines via N-Acyl N,O-Hemiacetal Formation

New procedures are described for the synthesis of α,β-ethylenic and acetylenic aldehydes from 2-butene- and 2-butyne-1,4-diol, respectively (see Scheme 1). These are applied to the preparation of a particular δ-acetylamino-α,β-ethylenic aldehyde ((E)- 5 ) as well as of its acetylenic analogue 15 . On heating in the presence of a silyl enol ether, the former undergoes a complete dehydrative cyclization affording the N-acetyl-1,2-dihydropyridine 19 . The addition of HCl to aldehyde (E)- 5 results in the production of the 4-chloro-1,2,3,4-tetrahydropyridine 22 which is hydrolyzed to the corresponding alcohol 23 on silica gel. Similarly, the addition of HCl or HBr to the δ-acetyl-amino-α,β-acetylenic aldehyde 15 leads to the previously unknown 4-halo-1,2-dihydropyridines 26 ; these are easily hydrolyzed to the 2,3-dihydro-4(1H)-pyridinone 27 . The ring-forming process involves a N-acyl N,O-hemiacetal as intermediate which is eventually dehydrated.     

一种简便合成2-丁炔-1,4-二醇衍生物的新方法

由2-丁炔-1,4-二醇可以很方便地得到2-丁炔-1,4-二氯,这一试剂在有机合成中有着广泛的应用。而在其它条件相同的情况下,制备2-丁炔-1,4-二溴并未得到相应较好的结果。我们用无水苯为反应溶剂,以温和的 (PPh3)PBr2作为卤代试剂(冰浴下液溴逐滴滴入PPh3苯溶剂中当场生成)卤化2-丁炔-1,4-二醇,选择性合成得到2-丁炔-1,4-二溴衍生物。同时也实现了2-丁炔-1,4-二醋酸酯的合成。     

Influence of pulse plating conditions on the structure and properties of pure and composite nickel nanocrystalline coatings

An additive-free Watts type bath containing micron- and nano-SiC particles (1 μm and 20 nm respectively), as well as ultrafine-WC particles (200 nm), was used for the production of pure Ni and nickel matrix composite electrocoatings under both direct and pulse current conditions. Moreover, nickel nanocrystalline deposits were obtained from a Watts type bath containing small amounts of 2-butyne-1,4-diol, in order to investigate the combined advantages of additives and pulse technique on the properties of the deposits. The influence of the variable electrolysis parameters, the particle size and the organic additive concentration on the surface morphology, the structure and properties of the deposits were discussed. It has been proved that the application of pulse electrodeposition affects drastically the structural characteristics and properties of the deposits and under well-defined conditions could lead to the preparation of nanostructured materials with improved mechanical properties. Published in Russian in Elektrokhimiya, 2008, Vol. 44, No. 6, pp. 802–811. The text was submitted by the authors in English.     

Copper(I) π-complexes with 2-butyne-1,4-diol. Synthesis and crystal structure of (2-AmpH)[CuCl<Subscript>2</Subscript>(HOCH<Subscript>2</Subscript>C≡CCH<Subscript>2</Subscript>OH)] (2-AmpH<Superscript>+</Superscript> is 2-aminopyridinium cation)

Crystals of the π-complex (2-AmpH)[CuCl₂(HOCH₂C≡CCH₂OH)] (2-AmpH⁺ is the 2-aminopyridinium cation) were obtained by the reaction of 2-butyne-1,4-diol with CuCl in aqueous 2-aminopyridinium chloride solution and studied by X-ray diffraction: space group P \(\overline 1 \), a= 7.172(4), b= 7.796(3), c = 11.60(9) Å, α = 99.75(6)°, β = 96.53(7)°, γ = 101.03(3)°, Z = 2. The crystals consist of individual anions [CuCl₂(HOCH₂C≡CCH₂OH)]^? and cations [2-AmpH]⁺. The π-coordinated Cu(I) atoms of the complex anion have trigonal-planar surrounding of two chlorine atoms and C≡C bond of the 2-butyne-1,4-diol molecule. The alcohol groups form stable hydrogen bonds N-H?O (1.89 Å) and O-H?Cl (2.20 Å).     

The influence of electrolyte composition on pH of nickel hydrate formation

The influence of the composition of nickel plating electrolytes containing various ligands (Ac⁻, Gly⁻, and Asp²⁻) on pH of nickel hydrate formation (pH_hydr) was studied. The data obtained were interpreted from the point of view of ionic equilibria in the systems studied. The nature of sparingly soluble precipitates formed in these electrolytes when pH_hydr was reached was determined. Sparingly soluble precipitates were found to be pure Ni(OH)₂ hydroxides or basic salts with the composition Ni(OH) _n Cl_{2 − n} , in which the content of chloride ions increased as the concentration of NiCl₂ grew. Organic substance anions were absent in the precipitates formed and only influenced pH_hydr through changes in the concentration of free nickel ions as a result of complex formation. A principle of selecting the composition of nickel plating electrolytes was suggested on the basis of the results obtained.     

2,3-Bis(diphenylphosphynyl)-1,3-butadiene via a double [2,3]-sigmatropic rearrangement. A reinvestigation of the reaction of 2-butyne-1,4-diol with chlorodiphenylphosphine

Contrary to previous reports, the reaction of 2-butyne-1,4-diol with chlorodiphenylphosphine yields 2,3-bis(diphenylphosphinyl)-1,3-butadiene 3 instead of the 1,4-isomer. The structure of the product has been elucidated from ¹H, ¹³C and ³¹P-NMR spectroscopic data.     

Preparation and Study of Some Copolyesters

Terephthalate unsaturated copolyesters with ethylene glycol and 2-butene-1,4-diol, with ethylene glycol and 2-butyne-1,4-diol, with ethylene glycol and diethylene glycol, and with 2-butyne-1,4-diol were synthesized by trans-esterification reactions. Proton nuclear magnetic resonance spectroscopy was used to elucidate the structures of the copolyesters. The intrinsic viscosities of the copolyesters were measured in o-chlorophenol at 30°C. The number-average molecular weights of these copolyesters were determined by using a vapor pressure osmometer. The thermal behaviors of the copolyesters were studied by differential thermal analysis and are discussed in terms of structural differences.     

A chemical study of 2-butyne-1,4-diol

Commercial grade 2-butyne-1,4-diol has been used in electroplating for several years. In laboratory experiments, its presence in the electrolyte increases the current efficiency of zinc electro-winning. Its chemical behaviour in solution is not well known. The present paper indicates that the brownish technical grade 2-butyne-1,4-diol contains the monomer, the dimer and some trimer. Pure monomeric 2-butyne-1,4-diol is a white solid obtained by evaporation of the technical grade product. The monomer is slowly transformed into dimer and possibly into a trimer when dissolved in water. Various analytical techniques were used in the study of this system. Factor analysis with column cross-validation was applied to chromatographic data to help in the resolution of the system.     

Synthesis, X-Ray Diffraction Data, and 1H and 13C NMR Spectra of N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines Derived from N-Aroyl(acetyl)-1,4-benzoquinonimines

Oxidation of N-(N-arylsulfonylimidoyl)-4-aminophenols gave the corresponding N-[N-arylsulfonylimidoyl)-1,4-benzoquinonimines, derivatives of N-aroyl- and N-acetyl-1,4-benzoquinonimines. The structure of the products was studied by the X-ray diffraction method and ¹H and ¹³C NMR spectroscopy. N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines were found to undergo fast (on the NMR time scale) Z E isomerization about the CÍN bond in the quinonimine fragment. N-(N-Arylsulfonylacetimidoyl)-1,4-benzoquinonimines in solution give rise to dynamic Z E-isomerization with respect to the CÍN bond in the N-arylsulfonylacetimidoyl fragment.     

Raman-spectrum investigation of 2-butyne-1,4-diol 2-butyne-1,4-diol diacetate,and 1,4-dichloro-2-butyne

Summary 2-Butyne-1,4-diol, 2-butyne-1,4-diol diacetate, and 1,4-dichloro-2-butyne exist in cisoid and transoid forms because of the operation of factors hindering free rotation of individual groups of atoms in these molecules around the corresponding single bonds.     

Analysis of products from hydrogenation of 2-butyne-1,4-diol

Conclusions A qualitative and quantitative method has been developed for analysis of a mixture of butane-1,4-diol, cis-2-butene-1,4-diol, trans-2-butene-1,4-diol, and 2-butyne-1,4-diol in the form of their diacetates by gas chromatography.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 942–944, April, 1970.     

Lipase-catalyzed polycondensation of dicarboxylic acid–divinyl esters and glycols to aliphatic polyesters

Lipase-catalyzed polymerization of dicarboxylic acid–divinyl esters with glycols has been performed. The vinyl esters used were divinyl adipate and divinyl sebacate. Lipases derived from Candida antarctica, Mucor miehei, Pseudomonas cepacia, and P. fluorescens showed high catalytic activity toward the present polymerization. Effects of solvent, reaction temperature, and enzyme amount were systematically investigated. A combination of divinyl adipate, 1,4-butanediol, and P. cepacia lipase afforded the highest molecular weight (2.1 × 10⁴). The yield of the polymer from divinyl sebacate was higher than that from divinyl adipate, whereas the opposite tendency was observed in the polymer molecular weight. Methylene chain length of α,ω-alkylene glycol also affected the polymerization behavior. The enzymatic polymerization of divinyl sebacate with cis-2-butene-1,4-diol and 2-butyne-1,4-diol resulted in the polymer containing unsaturated group in the polymer backbone. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2737–2745, 1999     

Reductive cleavage of C-OH bonds in allyl position-formation of gaseous products in the course of the cathodic reduction of some simple unsaturated alcohols

The problem of the reductive cleavage of C?OH bonds in allyl position has been considered starting from the literature data concerning the behaviour of allyl alcohol. The formation of hydrocarbons has been shown in the case of the electroreduction of crotyl alcohol, 2-butene-1,4-diol, propargyl alcohol, 2-butyne-1,4-diol and 1-butyne-3-ol. The composition of the gaseous products was analyzed, current efficiency values with respect to the hydrocarbon formation were calculated. Schemes for the reduction path were given.