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。     

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.     

Procedures for recovery of crystalline 2-butyne-1,4-diol from industrial aqueous solutions and for its purification

Four procedures for recovery of crystalline 2-butyne-1,4-diol from aqueous solutions and for its purification were examined. Samples of crystalline 2-butyne-1,4-diol containing 98.5 to 99.9 wt % target product were obtained.     

Catalytic hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol at atmospheric pressure in the liquid phase

Selective hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol on suspended palladium and Raney nickel catalysts at atmospheric pressure was studied. The optimal parameters of this reaction were determined. Samples containing 90% 2-butene-1,4-diol were prepared.     

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.     

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.     

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.     

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.     

Rearrangement of 2-butyne-1,4-diol to butyrolactone catalyzed by ruthenium complexes

The isomerization of 2-butyne-1,4-diol to butyrolactone catalysed by ruthenium complexes is described.     

Liquid-phase catalytic hydrogenation of 2-butyne-1,4-diol to 1,4-butanediol at atmospheric pressure on suspended catalysts

The optimum parameters of hydrogenation of 2-butyne-1,4-diol to 1,4-butanediol on the suspended palladium and Ni-Raney catalysts at atmospheric pressure were found. In selected conditions a yield up to 90% of 1,4-butanediol was reached.     

The flammability properties of copolyesters and copolycarbonates containing acetylenes

The flammability properties of copolyesters and copolycarbonates containing varying percentages of 2-butyne-1,4-diol and 2,4-hexadiyne-1,6-diol were studied by use of oxygen index and dynamic thermogravimetry. The char formation was found to increase with increasing polymer unsaturation. For nonconjugated acetylenes there is an increase in the oxygen index with increasing unsaturation in a polymer. In contrast, conjugated acetylenes dramatically decrease the oxygen index of a polymer system.     

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.     

Stereochemistry of additions to a triple bond

Summary In the photochemical bromination of 2-butene-1,4-diol, its diacetate, and 2,5-dimethyl-3-hexene-2,5-diol in nonpolar solvents, trans-addition products are formed, whereas their acetylenic analogs give mainly cis-dibromides. The differences in the behavior of acetylenes and the corresponding olefins are to be explained on the view that under identical conditions they may react by different mechanisms. Thus, under given conditions 2-butyne-1,4-diol diacetate is brominated by a chain mechanism, whereas the corresponding olefin is brominated by a nonchain mechanism.     

Effect of Chloride Ions on the Behavior of Saccharin, N-Methylsaccharin, and 2-Butyne-1,4-diol during Electrodeposition of Nickel from Acid Electrolytes

Rates of transformation of organic additives (saccharin, N-methylsaccharin, 2-butyne-1,4-diol) and accumulation of products of their cathodic reactions are studied during nickel electrodeposition from the chloride and Watts electrolytes. A large concentration of chloride ions accelerates the saccharine and N-methylsaccharin consumption due accelerated synthesis of o-toluenesulfamide, N-methyl-o-toluenesulfamide, and N-methylbenzylsultam, thus facilitating adsorption of additives on the nickel cathode via the carbonyl group. An inhibition of adsorption via the sulfonyl group is accompanied by a decrease in the accumulation of corresponding benzamides. An increase in the concentration of chloride ions in electrolytes containing 2-butyne-1,4-diol promotes accumulation of 2-buten-1,4-diol and inhibits hydrogenation of the double bond to a saturated bond. Differences in the behavior of the additives are due to (i) competition of chloride ions with the additives in the electrolyte or with their electroreduction products during adsorption on the nickel cathode, (ii) a change in the deposit potential, and (iii) a change in the concentration of inclusions in the deposits, which determine the catalytic activity of the cathode.     

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.     

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.     

Triply fused Zn(II)-porphyrin oligomers: synthesis, properties, and supramolecular interactions with single-walled carbon nanotubes (SWNTs)

The photophysical, electrochemical, and self-assembly properties of a novel triply fused Zn(II)-porphyrin trimer were investigated and compared to the properties of a triply fused porphyrin dimer and the analogous monomer. The trimer exhibited significantly red-shifted absorption bands relative to the corresponding monomer and dimer. Electrochemical investigations indicated a clear trend in redox properties amongst the three porphyrin structures, with the lowest oxidation potential and the lowest HOMO-LUMO gap exhibited by the triply fused trimer. This electrochemical behavior is attributed to the extensive pi-electron delocalization in the trimeric structure relative to the monomer and dimer. Additionally, it was found that the trimer forms extremely strong and nearly irreversible supramolecular interactions with single-walled carbon nanotubes (SWNTs), resulting in stable solutions of porphyrin-nanotube complexes in THF. Formation of these complexes required the addition of trifluoroacetic acid (TFA) to the solvent. This allowed the oligomers to make close contact with the nanotubes, enabling the formation of stable supramolecular assemblies. Atomic force microscopy (AFM) was used to observe the supramolecular porphyrin-nanotube complexes and revealed that the porphyrin trimer formed a uniform coating on the SWNTs. Height profiles indicated that nanotube bundles could be exfoliated into either individual tubes or very small bundles by exposure to the porphyrin trimer during sonication.     

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.     

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.     

Photochemistry of heterocycles: VIII. photocycloaddition of acetylenic compounds to 1,3-dimethyl-6-azathymine

The photocycloadditions of 1,3-dimethyl-6-azathymine to 2-butyne-1,4-diol and 1,4-dimethoxyl-2-butyne have been studied. Three novel compounds, 7,8-bis(hydroxymethyl)-3,5-dioxo-2,4, 6-trimethyl-1,2,4-triazabicyclo [4,2,0]-7-octene (1), 7,8-bismethoxymethyl-3,5-dioxo-2,4,6-trimethyl- 1,2,4-triazabicyclo[4,2,0]-7-octene (2) and 8,9-bismethoxymethyl-4-oxo-1,3,5-trimethyl-7-oxa-2,3,5-triazaspiro[5,3]- 1,8-nonadiene (3) were obtained. The proposed reaction mechanism, which includes excited triplet complexes and biradicals as intermediates, was supported by kinetic and photophysical studies.