Methyl succinate

Most are very sparingly soluble in water note however that methyl formate, methyl oxalate, methyl succinate, methyl and ethyl tartrate, methyl and ethyl citrate are soluble in water. 

Ethyl oxalate is the only liquid ester which gives this rapid separation of the amide, which is therefore characteristic. Methyl and ethyl formate react rapidly with ammonia, but the soluble formamide does not separate methyl succinate gives crystalline succinamide after about I hour s standing, other esters only after a much longer time. The solid esters, other than methyl oxalate, are either soluble in water and remain so when treated with ammonia, or alternatively are insoluble in water and hence clearly not methyl oxalate. 

This product is identical with the 3-acetate of the minor product formed in the solvolysis of rockogenin 3-methyl succinate-12j5-mesylate (144a). 

Recently, a series of chiral diphosphines (S. -Me-Duphos, (S. -chiraphos, (R,R)-diop and (+)-Norphos were grafted after an ionic exchange onto Al-MCM-41 134 complexes of the form [Rh(cod)(diphosphine)]+ were tested for the hydrogenation of dimethylitaconate. The supported complex with (S,S)-methyl-Duphos reached an activity for the formation of dimethyl ( -methyl-succinate as high as TON = 4000 with an ee close to 92%. Both (R,R)-diop and (,S S )-chiraphos give lower enantioselectivities (ee = 34% and 47% respectively). With (+)-Norphos, dimethyl-([Pg.457]

Further since XXV formed a quasi racemic compound with (+) methyl succinic acid XXVI, they have opposite configurations and so XXIV and XXVI have the same configuration. 

The photo-Fries rearrangement of aryl hydrogen (or methyl) succinates 267 leads to 4-(2-hydroxyaryl)-4-oxobutanoic acids (or methyl esters 268), which are readily cyclized to 5-(2-acetoxyaryl)-2(3//)-furanones (269) (Scheme 68). [189-191] Photolysis of 269 [191] or the analogous open-chain enol acetates [192,193] leads to chromones. 

Deng also showed that (DHQD)2AQN could catalyze the parallel KR (PKR) of a variety of monosubstituted succinic anhydrides via asymmetric alcoholysis [215]. The nature of the solvent was found to have a significant influence on the selectivity. Hence, increasing the size of the alcohol from methanol to ethanol resulted in increased levels of enantioselectivity, albeit with reduced reaction rates. In this context, 2,2,2-trifluoroethanol appeared to be the alcohol of choice as it allowed the ASD of 2-methyl succinic anhydride (58a) with a remarkable level of selectivity. Indeed, the use of (DHQD)2AQN (15 mol%) provided a mixture of two regioiso-meric hemiesters 59a and 60a in a 1 1 ratio with 93 and 80% ee respectively. 

Because the liquid phase enthalpy of formation of the corresponding t-butyl methyl succinate ester is available, —950.9 3.0 klmol", the enthalpy of reaction 16 can be calculated. The result, —72.8 3.9 kJ mol , is nearly the same as that for the esters and peresters above, —70.3 8.1 kJmol. ... 

The quinazolinone moiety (36-3) for the cardiotonic agent prindoxan (36-5) is formed by reaction of diamine (36-1) with carbonyl diimidazole (36-2). Friedel-Crafts acylation of the product with the half-acid chloride from methyl succinate gives the corresponding keto-ester (36-4). The pyridazinone (36-5) is then obtained by condensation of that product with hydrazine [38]. 

Methyl hydrogen succinate has been prepared by heating succinic acid with methyl succinate,2 by treating ethyl succinate with sodium methoxide,3 and by heating succinic anhydride with methanol.4 5 ... 

By polymerizing methylsorbate in the presence of catalysts obtained from optically active compounds containing (1R, 3R, 4S)-l-methyl-4-isopropyl-cyclohex-3-yl group, the methyl succinic acid formed by oxidation has the absolute structure (XV) thus in the polymer the tertiary carbon atoms bound to the methyl group have the absolute configuration (R) (XVI). The same steric correlation has been found in the case poly-styrylacrylic esters. 

Actually, levo rotatory methyl succinic acid and dextro rotatory methyl succinic acid were obtained by oxidation respectively from methyl sorbate and butyl sorbate polymers, obtained in the presence of (R)-2-methyl-butyl-lithium (36). 

In fact sorbic acid (XXXIII) has been transformed in menthyl-sorbate and the ester (XXXIV) has been polymerized (36) by butyl-lithium (Scheme 6) the prevalence of asymmetric carbon atoms having one of the possible configurations in the main chain of the polysorbic acid (XXXV), not isolated by the authors, has been proved by oxidizing the polymer and measuring the optical activity of the obtained methyl succinic acid, which actually was optically active and had an optical purity of 6% (36). 

AE55 c5h804 methyl succinic acid hoocch(ch3)ch2 DMSO PY E14NC104 0.1 - - 23.0 DME/SCE 035A. ... 

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