Butane-1,2,3,4-tetracarboxylic acid

These are esters of polybasic acids (e. g., malonic acid, citric acid, propane 1,2,3-tricar-boxylic acid, butane 1,2,3,4-tetracarboxylic acid) with long-chain alcohols. 

Pyro-EMA tetramethacryloyloxyethyl pyrophosphate TCB butan-1,2,3,4-tetracarboxylic acid di-2-hydroxyethylmethacrylate ester TEG DMA triethylene glycol dimethacrylate TMPTMA trimethylolpropane trimethacrylate... 

In addition, compomers contain extra monomers from conventional composites, and these contain acidic functional groups. The most widely used monomer of this type is so-called TCB, which is a di-ester of 2-hydroxyethyl methacrylate with butane tetracarboxylic acid [271]. This acid-functional monomer is a very minor component and compomers also contain some reactive glass powder of the type used in glass-ionomer cements [266]. 

Dimethyl maleate is being electrochemically converted to 1,2,3,4-butane tetracarboxyllic acid. 

On an industrial scale, the traditional method for cleavage of carbon-carbon double bonds is ozonolysis, used for the manufacture of azelaic acid and nonanoic acids from oleic acid, and of butane tetracarboxylic acid from tetrahydrophthalic anhydride. The process is effectively a quantitative and mild process.178 However, it is capital and energy intensive. The intermediate ozonide is worked up either reductively or oxidatively to produce the aldehyde, ketone or carboxylic acid. Hydrogen peroxide is the common oxidizing agent used in the second step.179-181 Oxygen can also be used either alone182 or in combination with zeolites.183 Reviews on ozonolysis are available and the reader is directed to reference 184 for further information. 

The details of the electrohydrodimerization of dimethyl maleate in methanol has been studied using Fourier transform infrared (FTIR) spectroscopy [339]. Spectra were recorded as a function of time at a constant applied potential (—1.5 V versus Ag/AgCl) with the reference spectrum being obtained at OV. The result is shown in Fig. 49(a) as plots of dR/R versus the wavenumber (cm" ), where R is the reference spectrum and dR is the sample spectrum minus the reference spectrum. Thus, positive dR/R values indicate loss of chromophore, while negative dR/R values indicate gain of chromophore. The analysis of the spectral data showed that the formation of the hydrodimer, 1,2,3,4-butane tetracarboxylic acid, is accompanied by isomerization of dimethyl maleate (the cis isomer) to dimethyl fumarate (the trans isomer). This is nicely illustrated by Fig. 49(b), from which it is seen that the loss of chromophore at 1390 cm" (cis isomer) proceeds more rapidly than the gain in chronomophore at 1288 cm" (trans isomer). 

Miscellaneous Reactions. Radiolysis at room temperature of diluted aqueous solutions of succinic acid produces 1,2,3,4-butane tetracarboxylic acid [1703-58-8] (122), which has numerous industrial and agricultural applications (eq. 12). 

Figure 12.15 Fixation of Cl Reactive Red 180 with various concentrations of potassium salts of tetracarboxylic acids [139]. K BTCA = Tetrapotassium butane-1,2,3,4-tetracarboxylate K B4CA = Tetrapotassium benzene-1,2,4,5-tetracarboxylate...

In case C where jc = 1 the acid will be 1,2,4-butane tricarboxylic acid and when x = 2 the acid will be 1,3,5,6-hexane tetracarboxylic acid if the 1,2- groups are linked head-to-tail, and the 1,3,4,6- isomer if linked head-to-head. 

Yakubchik and his co-workers (1956, 1959 and 1962) have preferred to separate the acid derivatives by means of partition chromatography and compared the results with those obtained from an artificial mixture of those acids expected to be present. In the case of Ziegler-Natta catalyzed polybutadienes with less than 1% 1,2- units the presence of 1,4-1,2-1,4 sequences was indicated by the identification of some 1,2,4-butane tricarboxylic acid. Examination of their chromatograms suggests, at most, just a trace of any hexane tetra-carboxylic acid so that only a very small amount, if any, of 1,4-1,2-1,2-1,4 structures were present. Furthermore, no trace of any 1,2,3-propane tricarboxylic acid was found so there was no positive sign of any branching at the a-methylene position. On the other hand in the case of rubidium-catalyzed poly butadienes, which, like other polybutadienes prepared by the use of alkali metal catalyst systems, have a high 1,2- content, both hexane tetracarboxylic acid and 1,2,3-propane tricarboxylic acid were present in the ultimate products of ozonolysis. 

These results are consistent with a random distribution of the various units. The probability of a random sequence of r similar units (e.g. 1,2- units) is given by p (l-p) where p is the fraction of such units in the total. For the Ziegler-Natta polymers described by Yakubchik p = c. 0 05 so that the molar ratio of butane tricarboxylic acid to hexane tetracarboxylic acid should be about 20 1 whilst for the rubidium-catalyzed polymers which had a 1,2- content of about 50% the ratio should be about 2 1 (experimental results c. 1 7 1). 

A substituted acetamidomalonic ester, tetraethyl 1 -acetamido-4-hydroxy-butane-l,l,3,3-tetracarboxylate, was used in the preparation of cis- and frans-pyrrolidine-2,4-dicarboxylic acids, cyclic analogs of glutamic acid (91TL3049). 

Commercially important polyesters, e.g. poly[l-(2-ethylenyl)-2,2,6,6-tetramethyl-4-piperidinylbutane dioate] (146) [190] were synthesized from l-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidines and suitable dicarboxylic acids. Another polymeric HALS was prepared by transesterification of oligoesters of tetramethyl-butane-l,2,3,4-tetracarboxylate with 22,6,6-tetramethyl-4-hydroxypiperidine and 1,10-decanediol [191]. Compound 147 is a similar polyester type HALS. An ester-amide chain is created during esterification of 2-(2,2,6,6-tetramethyl-4-piperidinylamino)ethanol and dimethyl adipate [192]. 

Tetraethyl butane-1,1,4,4-tetrtacarboxylate added to a soln. of Na in abs. alcohol, to the resulting soln. tetraethyl l,4-dibromobutane-l,l,4,4-tetracarboxy-late added, and heated 4 hrs. in an oil bath at no-IIS -> tetraethyl cyclobutane-1,1,2,2-tetracarboxylate (Y 75.2%) boiled with aq. HGl (1 1) at ISO-HO in an oil bath until the oily layer has dissolved after 35-40 hrs., the HGl removed by distillation, and the residue heated at 180-200° until G0.2-evolution ceases mixture of cis- and frans-cyclobutane-l,2-dicarboxylic acids (Y 97.5%) refluxed 5 hrs. at 70-90° with acetjd chloride on a water bath, excess acetyl chloride and the resulting acetic acid removed by distillation at atmospheric pressure, and the residue heated 6-7 hrs. at 160-175° in an oil bath whereby the mixed anhydride of frans-cyclobutane-l,2-dicarboxylic acid and acetic acid is converted to acetic anhydride and cis-cyclobutane-l,2-dicarboxylic acid anhydride (Y 81.2%) boiled with 2 parts of water cis-cyclobutane-l,2-di-carboxylic acid (Y ca. 100%). V. P. Gol mov and Z. P. Malevannya, 7K. 31, 665 (1961) G. A. 55, 22162b method of ring closure s. J. J. Lennon and W. H. Perkin, Soc. 1928, 1513. 

---