Succinic acid, Tetramethyl

Disubstituted acids Dimethyl-succinic acids—Diethyl-succinic acids—Tetramethyl-succinic acid—Methyl-acrylic acid—Ethyl-crotonic acid. [Campholytic acid—Campho-thetic acid—Allocampholytic acid—Laurolene.].38-42... 

As shown in equation 12, the chemistry of this developer s oxidation and decomposition has been found to be less simple than first envisioned. One oxidation product, tetramethyl succinic acid (18), is not found under normal circumstances. Instead, the products are the a-hydroxyacid (20) and the a-ketoacid (22). When silver bromide is the oxidant, only the two-electron oxidation and hydrolysis occur to give (20). When silver chloride is the oxidant, a four-electron oxidation can occur to give (22). In model experiments the hydroxyacid was not converted to the keto acid. Therefore, it seemed that the two-electron intermediate triketone hydrate (19) in the presence of a stronger oxidant would reduce more silver, possibly involving a species such as (21) as a likely reactive intermediate. This mechanism was verified experimentally, using a controlled, constant electrochemical potential. At potentials like that of silver chloride, four electrons were used at lower potentials only two were used (104). 

It is an Intelcsting fact, not yet fully explained, that the alkyl succinic acids give anhydrides more readily than succinic acid, and the greater the number of alkyl groups, the more readily is the anhychidc produced. Ihus the anhydride of tetramethyl succinic acid is so stable that it is not decomposed by water. 

This synthesis has one rather anomalous application, when a-bromo-isobutyric acid (or its ethyl ester) is heated with silver, some tetramethyl-succinic acid is produced in the ordinary way (B., 23, 297 26, 1458). But there also appears trimethylglutaric acid (A., 292, 220). To explain the unexpected formation of this acid, it has been assumed that a portion of the a-bromoisobutyric acid gives up HBr to form methylacrylic acid. This latter then forms j3-bromoisobutyric acid, and the silver withdraws bromine from the a- and /3 acids, whereby the residues unite to tri-methyl-glutaric acid (B., 22, 48, 60). A similar explanation applies to some other syntheses in which tetramethylsuccinic and trimethylglutaric acids appear together. 

In a continuation of earlier128 studies on methylated derivatives of methyl L-sorboside, Khouvine and Arragon129 were able to isolate xylo-trimethoxyglutaric acid (LVI), as well as the dextrorotatory dimethoxy-succinic acid (LVII), by oxidation of either sirupy tetramethyl-L-sorbose (LV) or the methyl L-sorboside. The formation of either acid indicates the pyranoside ring in the original compounds. 

Iithyl -potassium dimethylmalonate affords tetramethyl-succinic acid. 

The yield of initiating radicals is, however, generally smaller than would be expected. In the case of AIBN this is because a certain amoxmt of tetramethyl-succinic acid dinitrile is formed by combination of the primary radicals, while some methacrylonitrile and Eo-butyronitrile are formed by disproportionation of the primary radicals. Azo compounds are especially suited as initiators for polymerization in bulk or in organic solvents. 

Chemical name (1,6-hexanediamine, N,N -bis(2,2,6,6-tetramethyl-4-piperidinyl)-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with, 1-(2-hydroxyethyl)-4-hy-droxy-2,2,6,6-tetramethyl piperidine-succinic acid, dimethyl ester,copolymer) ... 

Polyester of succinic acid with N-/9-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine... 

Fractionation of the methyl esters of the crude fraction of oxidation acids, provided evidence of the presence of five acids including probably methylsuccinic acid with some succinic acid. A tetramethyl ester, Ci4H220g, m.p. 65-6°, + 22-0° (MeOH), gave on hydrolysis a hexane-... 

When methyl a-L-sorboside was methylated and the resulting penta-methyl derivative was hydrolyzed, a tetramethyl-L-sorbose was obtained. Oxidation of the latter with nitric acid gave dextrorotatory dimethoxy-succinic acid126 (LVII), from which fact it became evident that a normal pyranoside structure is present in the methyl a-L-sorboside, since this dimethoxysuccinic acid could only have arisen if carbons 4 and 5 were methylated. From a comparison of the rate of hydrolysis of ethyl a-L-sorboside126 with the methyl a-derivative the authors assumed that it... 

There is abundant information to support the contention that the lower-melting monoisopropylidene-mannitol (m. p. 85°) is the 3,4-derivative. For example, its tetrabenzoate is identical with that obtained by acetonation of 1,2,5,6-tetrabenzoyl-mannitol,11498 the structure of which is based on independent evidence.114 The larger fragment resulting from the oxidative scission of the D-enantiomorph of the isopropylidene-man-nitol with lead tetraacetate is 2,3-isopropylidene-D-//treo-dihydroxy-succinic dialdehyde, characterized by its subsequent conversion into D-i/ireo-tartaric acid.126 When methylated and hydrolyzed, the L-enantio-morph of the monoketal affords a tetramethyl-mannitol, which, in turn, yields dimethyl-L-glyceraldehyde with lead tetraacetate.127 Each of these facts is in itself proof that the acetone residue occupies the 3,4-position in the mannitol molecule. 

Tocophersolan CAS 9002-96-4 30999-06-5 Synonyms Butanedioic acid, mono [3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecy)-2H-1-benzopyran-6-yl] ester, polymer with oxirane (1 22) Poly (oxy-1,2-ethanediyl), a-(4-((3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl) oxy)-1,4-ioxobutyl)-u)-hydroxy-, (2R-(2R(4R,8R)))- Tocofersolan a-Tocopheryl PEG 1000 succinate d-a-Tocopheryl PEG 1000 succinate Classification Organic compd. 

Bis(4-Hydroxy-2,6-dichloro-3-methox) henyl)methane, 75 l,l-Bis-(4-iodophenyl)ethane, 75 4,4 -Bis(2-methoxystyryl)biphenyl, 53 Bis(l-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, 194 Bis(l,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di-ferf-butyl-4-hy-droxybenzylmalonate, 194 Bis(l,2,2,6,6-pentamethyl-4-piperidyl)sebacate, 194 Bisphenol A, 17, 83, 244 N,N -Bis(saUcyloyl)hydrazide, 167,169 N,N -Bis(salLcyloyl)oxalyl dihydrazide, 169 N,N -Bis(salicyloyl)thiopropionyl dihydrazide, 169 Bis(stearoyl)ethylenediamine, 90 Bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, 194 Bis(2,2,6,6-tetramethyl-4-piperidyl)succinate, 194 Boron nitride, 32 Bromelain, 148 1,3-Butadiene, 74 Butanetriol trinitrate, 20 2-Butoxyethanol, 205 n-Butyl acetate, 216 n-Butyl alcohol, 218 4-ieri-Butylbenzoic acid, 123 Butyl benzyl phthalate, 11... 

Fig. 9.59 Plot of temperature of maximum spherulite growth rate, Tmax, against equilibrium melting temperature. I m, for indicated polymers. (1) isotactic poly(styrene) (a) (2) poly(tetramethyl-p-silphenylene siloxane) (b) (3) poly(cis-isoprene) (c) (4) poly(caproamide) (d,e) (5) poly(L-lactic acid) (f) (6) poly(phenylene sulfide) (g,h) (7) poly(R-epichlorohydrin), poly(S-epichlorohydrin), poly(I-RS-epichlorohydrin) (i) (8) poly(ethylene terephthalate) (j,k,l) (9) poly(aryl ether ether ketone) (m,n) (10) poly(ethylene-2,6-naphthalene dicarboxylate) (n) (11) poly(3-hydroxybutyrate) (o) (12) isotactic poly(methyl methacrylate) (q) (13) poly(dioxolane) (r) (14) New TPI poly(imide) (s) (15) poly(methylene oxide) (t) (16) poly(cis-butadiene) (u) (17) poly(propylene oxide) (v,w) (18) poly(imide) BPDA - - 134 APB (x) (19) poly(imide) BPDA - -C12 (x) (20) syndiotactic poly(propylene) (y) (21) poly(3-hydroxy valerate) (z) (22) poly(ethylene succinate) (aa) (23) poly(aryl ether ketone ketone) (bb) (24) poly(phenylene ether ether sulfide) (cc) (25) poly(tetramethylene isophtha-late) (dd) (26) poly(hexamethylene adipamide) (e,ee) (27) poly(tetrachloro-bis-phenol-A adipate) (fQ nylon 6-10 (ee).

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