Dimethyl succinate, oxidation

Degradation of 49 at 0°C in a HCl-saturated toluene solution gave Cp2TiCl2 in quantitative yield and dimethyl succinate in 60% yield. Air oxidation at 0°C of a toluene solution of 49 yielded dimethyl fumarate quantitatively. 

The catalytic dicarbonylation of ethylene to dimethyl succinate can be carried out in 90% conversion.94 High reaction temperatures and low carbon monoxide pressures can lead to unsaturated esters as a result of a faster -hydride elimination from the intermediate (23) than carbon monoxide insertion. This later reaction path has been termed oxidative carboxylation. 

DIMETHYL SUCCINATE (106-65-0) Combustible liquid (flash point 185°F/85°C cc). Reacts with strong oxidizers, with a risk of fire or explosions. Incompatible with strong acids, nitrates. 

This was followed shortly by a stereo- and enantiocontrolled synthesis of (—)-chimonanthine (154) and calycanthine (150) as well as a second route to meso-chimonanthine (152). The central step in this synthesis features the use of a double Heck cyclization to create vicinal quaternary carbon centers in high yields and with complete stereocontrol 124). The synthesis commenced with a double alkylation of the lithium dienolate of dimethyl succinate 194 and tartrate-derived diiodide 195 to give a diastereomeric mixture of the saturated diesters. Subsequent oxidation of the diesters, followed in succession by aminolysis, A-benzylation, removal of the benzyl ethers, and silylation, provided the cyclization substrate 197, which on Heck cyclization yielded a single product, 198, a pentacyclic bisoxindole, subsequently shown to have the meso relationship of the two oxindole groups. Further manipulations of 198 led eventually to the diazide derivative 199, which can be processed to we.so-chimonanthine (152), following the procedure established in the preceding synthesis (Scheme 14). 

DBDPO. See Decabromodiphenyl oxide DBE. See Ethylene dibromide DBE-4. See Dimethyl succinate DBE-5. See Dimethyl glutarate DBE-6. See Dimethyl adipate DBE-224, DBE-621, DBE-712, DBE-814, DBE-821. See Dimethylsiloxane/EO copolymer DBE-C25. See EO/dimethylsiloxane/EO block copolymer... 

Decylamine oxide Dicocodimethylamine dimerate Dihexyl adipate Diisodecyl adipate Diisostearyl fumarate Dilinoleic acid Dimethyl adipate Dimethyl succinate Dioctyl adipate Dioctyl sebacate... 

DMSS is synthesized from dimethyl succinate (DMS). Initiated by sodium meth-oxide, the initial Claisen condensation is followed by rapid cycUzation (Scheme 18.2), affording the product initially as the disodium salt 8, which after acidification yields 7 [8]. Although it may be considered as a cyclic di-P-keto diester, DMSS has been demonstrated [8A] to exist in the enol form (dihydroxycyclohexadiene diester 7), in both the soUd state and in solution, stabiUzed by intramolecular hydrogen bonding between the adjacent hydroxyl and ester carbonyl groups. 

L-dihydroxy-succinic acid (L(dexiro)-tartaric acid, CXIII). This result establishes the position of the double bond between C4 and C5 and demonstrates that C4 carries only one hydrogen atom while C5 has attached to it the enolic hydroxyl group. Treatment of the enol CXI with ethereal diazomethane gives 5-methyl-A4-D-glucosaccharo-3,6-lactone methyl ester (CXIY) which upon further methylation with silver oxide and methyl iodide yields 2,5-dimethyl-A4-D-glucosaccharo-3,6-lactone methyl ester (CXV). When the latter is subjected to ozonolysis there is formed oxalic acid and 3-methyl-L-threuronic acid (CXVI). Oxidation of this aldehydic acid (CXYI) with bromine gives rise to a monomethyl derivative (CXVII) of L-ilireo-dihydroxy-succinic acid. 

Groups of reportedly photochromic systems which deserve further study include (a) disulfoxides (123,124), (b) hydrazones (125-129), (c) osazones (130-133), (d ) semicarbazones (134-143), (e) stilbene derivatives (144), (/) succinic anhydrides (145-148), and (g) various dyes (149,150). A number of individual compounds also remain unclassified as to their mechanism of photochromic activity. These include o-nitro-benzylidine isonicotinic acid hydrazide (151), 2,3-epoxy-2-ethyl-3-phenyl-1-indanone (152), p-diethyl- and p-dimethyl-aminophenyli-minocamphor (153), brucine salts of bromo- and chloro-nitromethionic acid (154), diphenacyldiphenylmethane (155,156), 2,4,4,6-tetraphenyl-1,4,-dihydropyridine (155,156), 2,4,4,6-3,5-dibenzoyltetrahydropyran (155,156), o-nitrobenzylidenedesoxybenzoin (157), p-nitrobenzylidene-desoxybenzoin (157), N-(3-pyridyl)sydnone (158,159), tetrabenzoyl-ethylene (160), and the oxidation product of 2,4,5-triphenylimidazole (161,162). 

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. 

The diester 87 with the same tetracyclic skeleton as 83 had previously been prepared by Paquette et al. via a domino Diels-Alder reaction of 5,5 -bicyclo-pentadienyl 84 with dimethyl acetylenedicarboxylate (Scheme 20) [73]. The key precursor 84 was obtained by iodine-induced oxidative coupling of the copper cyclopentadienide derived from the sodium derivative. The diester 85 formed along with 86 was transformed into a bissilyl bisenol ether by reductive cleavage of the central bond in the succinate moiety with sodium in the presence of trimethylsilyl chloride. Subsequent hydrolysis of the bisenol ether - actually a bisketene acetal - gave the dienic tetraquinacenedicarboxylate 87. This compound served as the key intermediate in the first synthesis of dodecahedrane 88 [74]. 

Many chemical reaction systems have been published for the modification of agrofibers. These chemicals include ketene, phthalic, succinic, maleic, propionic and butyric anhydrides, acid chlorides, carboxylic acids, many types of isocyanates, formaldehyde, acetaldehyde, difunctional aldehydes, chloral, phthaldehydic acid, dimethyl sulfate, alkyl chlorides, beta-propiolactone, acrylonitrile, ethylene, propylene, and butylene oxide, and difunctional epoxides [35,36]. 

Octenylsuccinic anhydride Propylene glycol Pyromellitic dianhydride Tallow acid Tetradecenyl succinic anhydride 1,1,3-Tris (hydroxyphenyl) propane m-Xylene intermediate, alkyl ether sulfates Isododecyl alcohol intermediate, alkyl phoshates Isododecyl alcohol intermediate, alkylated aromatics C14-16 alpha olefin intermediate, alkylation Diphenyl oxide intermediate, allethrin Dimethyl hexanediol intermediate, alpha olefin sulfonates C14-16 alpha olefin intermediate, alpha-olefins Ethylene... 

A recent advancement consists of the nse of triphenylphosphine sulfide as ligand under conditions of oxidative carbonylation. Thus, styrene could be dicarbonylated to phenyl-succinic dimethyl ester in 80% yield at room temperature and atmospheric pressure. Enantioselection was observed with chiral bisphosphine sulfides. 

Of particular interest is the oxidation of the complexes Fea CjoH R Og (XXXI R = R = CH3 or H) with aqueous ferric chloride to give a product of composition (RC2R)Fe(CO)6 [190). Oxidation of the dimethyl derivative with cold concentrated nitric acid gives dimethylmaleic anhydride (XXXII). The derivative (HC2H)Fe(CO)6 forms a Diels-Alder adduct (XXXIII) with cyclopentadiene the adduct may be oxidized to succinic acid. All of these data indicate that the derivatives (RC2R)Fe(CO)6 are cyclic derived from maleic acid derivatives. Four of the six carbonyl groups are metal... 

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