Acetylene-dicarboxylic acid

Bamford and Mullik [23] have also investigated a new photoinitiating system composed of Mn2(CO)io or Re2(CO)io with acetylene, acetylene dicarboxylic acid, diethyl fumarate, diethyl maleate, or maleic anhydride. It was concluded that the primary radical responsible... 

Eimhjellen, K. Bacterial Dissimilation of Acetylene Dicarboxylic Acid. 

Scheme 12.8 Hydrogenation of acetylene dicarboxylic acid dimethylester to the corresponding maleate [8 a].

But catalytic reduction of the same phenyl propionic acid gives cis cinnamic acid. Therefore by adding hydrogen under various conditions, one can obtain a desired isomer. The conversion of acetylene into olefinic compounds has been carried out not only for the sake of obtaining the adduct, but Michael studied the various addition reactions for the sake of obtaining a desired product cis or trans. For example, he found that the addition of bromine to acetylene-dicarboxylic acid leads predominantly to the formation of trans isomer. 

A Ag/Pd-cathode hydrogenates 2-butyne-1,4-diol and acetylene dicarboxylic acid exclusively to the cis-olefin [323]. Similar results were obtained at a Cu net covered with spongy silver [324]. With dimethyl butynedioate the cis/trans ratio of the product dimethyl butenedioate on a Pd black cathode decreased with increasing pH both in electrolytic and catalytic hydrogenation [325]. On the other side at a Hg cathode a trans addition to alkynes occurs [326]. In methy-lamine/liCl, dialkylacetylenes are reduced to trans-olefins. Nonconjugated aromatic internal acetylenes are selectively reduced to aromatic trans-olefins [327]. 

The oxidation of propargyl alcohol to the acid and of but-2-yne-l,4-diol to acetylene dicarboxylic acid is carried out on a technical scale at a lead dioxide anode in sulphuric acid [4, 5]. Electrochemical oxidation of acetylenic secondary alcohols to the ketone at lead dioxide in aqueous sulphuric acid [4], gives better results than the cliromic acid based process of Jones [6], Oxidation of aminoalkan-1-ols to the amino acid at a lead dioxide anode in sulphuric acid is achieved in 31 -73 % 5delds [7]. This route is applied to the technical scale production of (l-alanine from 3-aminopropanol in an undivided cell [8]. 

Diiodofumaric Acid (Dijodfumarsaure in Ger) (Called Acetylencarbons3ure by Bruck) HOOC.CI CI.COOH, mw 303.90 ndls (from eth. +benz) or crysts (from eth +toluene), mp — dec at l92°sol in w, ale, eth, acet acid insol in benz, chlf petr eth prepd by heating acetylene dicarboxylic acid with iodine in ale or in chlf at 100°... 

Only the 1-benzyl-vic-triazole, crysts(from eth at 20°), mp 61°, appears to have been prepd and reported in the literature. Curtius Raschig(Ref 2) prepd 1-benzyl-vic-triazole by the reaction of benzyl azide with the methyl ester of acetylene-dicarboxylic acid, followed by sapon and decarboxylation. Wiley et al(Ref 3) prepd the compd directly and in better yield from acetylenedicar-boxylic acid, followed by decarboxylation to 1 -benzyl-vic-triaZole(77% yield)... 

The direct anodic oxidation of 1,4-butynediol at Pb02 anodes in sulfuric acid yields the desired acetylenic dicarboxylic acid [11] ... 

R1 = N3 R2 = OH) were useful compounds (see Section II,D). The starting materials 55 had been synthesized via Diels-Alder reaction of acetylene-dicarboxylic acid with 2,3-dialkyl-1,3-butadienes, followed by oxidation (85USP4532301 85USP4556512). Yoshida et al. condensed the doubly cross-conjugated cyclopentadiene 57 with hydrazine to obtain 1,2-diazocine 58 (84TL4223) (For structural studies of 58, see Section II,B.)... 

Ingold (1) has mentioned that the older literature contains several observations indicating the existence of stereochemically favorable and unfavorable situations for elimination reactions leading to acetylenic compounds. For instance, Michael (2) found that chlorofumaric acid (4) is converted by alkali about 50 times faster than in chloromaleic acid (5) into acetylene dicarboxylic acid (6). Chovanne (3) has observed that cis-dichloroethylene (7) is transformed by alkali about 20 times faster than is the trans-isomer 8 into chloroacetylene (9). 

On the other hand, acetylenic alcohols can be electrochemically converted to the corresponding acetylene carboxylic acids in acidic electrolytes using Pb02 anodes. Processes for the synthesis of propynoic acid and acetylene dicarboxylic acid have been developed at BASF 303 - 30. ... 

The copper derivative of this compound cum nisei be condensed in the presence of forricyanido, mid tetr-acetylene-dicarboxylic acid results ... 

Electrolytic oxidation gives acetylene dicarboxylic acid (2-butyne-dioic acid) in good yields. Butynediol can be hydrogenated partway to butenediol (HOCH2CH=CHCH2OH) or completely to butanediol (HOCH2CH2CH2CH2OH). 

A variety of organic transformations in aqueous media using BDD anodes have been studied. The pronounced stability of the BDD material in the presence of water makes it obvious that is should be used in oxidation processes. However, the yields are usually low and therefore less attractive for synthetic purposes. The BASF company investigated the anodic oxidation of butyn-l,4-diol 32. The anodic treatment in an electrolyte of dilute sulfuric acid gave small amounts of the monoacid 33 and the acetylene dicarboxylic acid 34. The moderate product efficiency might be attributed to electrochemical incineration processes (Scheme 15). 

C6H404)t Acetylene dicarboxylic acid dimethyl ester 600 g, 238... 

In order to confirm the proton transfer mechanism proposed previously [160], the results of IQNS on terephthalic acid were reported [164]. The jump distance is calculated to be 0.7 A for the proton transfer model and 2.1 A for the 180° rotation model - the latter process was ruled out on the basis of the experimental IQNS results, leading to the conclusion that the mechanism of the proton dynamics is indeed a double proton exchange. IQNS results for terephthalic acid and acetylene dicarboxylic acid have also been reported [165]. For both samples, the jump distance was found to be less than 1 A. For acetylene dicarboxylic acid, single crystal measurements yielded a jump distance of 0.73 A. The Q-depen-dence was found to be in excellent agreement with the 2-site jump model. From these results, the 180° rotation model can be ruled out in favour of the proton transfer model. 

Electrolytic oxidation gives acetylene dicarboxylic acid [142-45-0] (2-butynedioic acid) hi good yields (49) chromic acid oxidation gives poor yields (50). Oxidation with peroxyacetic acid gives malonic acid [141-82-2] (qv) (51). 

The reaction of 28 with acetylene dicarboxylic acid or DMAD furnishes 48a [71 JCS(C)3602] and 48b [71JCS(C)3602 77MI1], respectively (Scheme 10). Compound 48b, synthesized by this reaction, was earlier formulated as imidazo-thiazinone (49) (67CJC939, 67CJC953) on the basis of mass spectral studies of the monocyclic system (thiazinone) obtained from thiourea and DMAD, whose structure is still in dispute. Evidence has been furnished that the reaction of DMAD with thiourea gives methyl (2-imino-... 

The reduction of acetylene dicarboxylic acid (or its monoethyl ester) leads to an interesting hydrodimerization reaction (Scheme 6). 

Crystal structure oxalic acid 21110, acetylene dicarboxylic acid 2HiO. 

More recently published ideas include the formation of solid derivatives of alkyl azides by treatment with acetylene dicarboxylic acid to form 1-alkyl-triazole-4,5-dicarboxylic acids. These frequently form hydrates with poor melting points and generally poor analytical properties. Alternatively, one can obtain bicyclic fused-ring triazolines by treatment with norbornadiene or dicyclopentadiene °. 

The most obvious route to vinyl azide synthesis lies in the addition of hydrazoic acid to an alkyne. Unfortunately, this reaction has been found to be successful with only one group of compounds, the esters of acetylene dicarboxylic acid (equation 1). Acetylene mono-... 

---