Dimethyl succinate

1 Dimethyl Succinate The symmetrical, conformationally mobile, open-chain diesters are worth examining. Dimethyl succinate  

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Succinamide. NHoCOCH2 CH2CONH2. (Method 2(a)). Add 5 ml. (5 8 g.) of dimethyl succinate to a mixture of 50 ml. of water and 25 ml. of concentrated [dy o-88o) aqueous ammonia solution in a 150 ml. conical flask. Cork the flask and shake the contents the dimethyl succinate rapidly dissolves to give a clear solution. Allow the solution to stand after about i hour the succinamide starts to crystallise, and then continues to separate for some time. Next day, filter off the succinamide at the pump, wash with cold water, and drain. Recrystallise from water, from which the succinamide separates as colourless crystals the latter soften at 240° and melt at 254 -255° with... 

Succinamide. Add 5 g. (4-8 ml.) of dimethyl succinate to 25 ml. of concentrated ammonia solution (sp. gr. 0-88) in a 100 ml. conical flask. Cork the flask and shake the contents for a few minutes aUow to stand for 24 hours with occasional shaking. Filter off the crystals of succinamide, and wash with a Uttle cold water. RecrystaUise from a little hot water. Dry in the steam oven and determine the m.p. The yield is 3-5 g. Pure succinamide melts at 254° with decomposition. 

Di lve 20 g. of the cyano ester in 100 ml. of rectified spirit and add a solution of 19 2 g. of pure potassium cyanide in 40 ml. of water. Allow to stand for 48 hours, then distil oflF the alcohol on a water bath. Add a large excess of concentrated hydrochloric acid and heat under reflux for 3 hours. Dilute with water, saturate the solution with ammonium sulphate, and extract with four 75 ml. portions of ether. Dry the combined ethereal extracts with anhydrous sodium or magnesium sulphate, and distil off the ether. RecrystaUise the residual acid from excess concentrated hydrochloric acid, and dry in the air. The yield of pure ew-dimethyl-succinic acid, m.p. 141-142°, is 12 g. 

Dimethyl succinate [106-65-0] (mp 19°C, bp 196°C at atmospheric pressure) can be produced from methanol and the anhydride or the acid, or by hydrogenation of dimethyl maleate (38,39). The same methods can be used to prepare diethyl succinate [123-25-1] (mp — 18°C, bp 216.5°C at atmospheric pressure) and diisopropyl succinate [924-88-9]. 

This process, to which the raw materials are suppHed at low pressures, is continuous and gives good yields of acrylates (see Acrylic acid and derivatives). In the presence of catalytic amounts of Co2(CO)g, acetylene has been carboxylated in methanol yielding dimethyl succinate as the principal product (135). 

Diesters dimethyl malonate, dimethyl succinate, dimethyl glu-tarate, and dimethyl adipate... 

Chemical name(s) Dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-l-piperidine... 

Solvent-assisted decaffeination of coffee can result in residues of solvent reaching the consumer.208 The use of chlorinated hydrocarbon solvents such as chloroform,209 methylene chloride, trichloroethylene,208 and difluoromonochloromethane (Freon),210 will probably be replaced by compounds already found in roasted coffee. The use of an ethyl acetate and 2-butanone mixture leaves a 26-ppm residue in green coffee, but zero residue in roasted coffee.211 Other solvent compounds used or suggested for coffee improvement or decaffeination include propane, butane,212 carbon dioxide,213 214 acetone215 dimethyl succinate,2161,1-dimethoxymethane, and 1,1-dimethoxyethane.217 Of all these, supercritical carbon dioxide, ethyl acetate, and methylene chloride are the solvents most used currently in decaffeination processes. 

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. 

Dimethyl succinate derivatives 187 eliminate a molecule of methyl ethanoate upon heating to give 1,2,4-triazoles 188a-e in reasonable yield. The reaction also produces the corresponding triazines but these are readily separated from the desired triazoles (Equation 59 and Table 40) <2001EJM93>. 

Table 40 Reaction of dimethyl succinates to give 1,2,4-triazole derivatives (Equation 59) ...

Diesters and even triesters have been converted to bis- and tris(cyclopropanol)s, respectively. Dimethyl succinate gave the bis (cyclopropanol) derivative 17 in 80% yield, while triethyl trans-cyclopropanetricarboxylate (18) yields the tris (cyclopropanol) 19 (90%) (Scheme 11.4 selected examples in Table 11.2) [77,78], Higher homologous dicarboxylic acid diesters are likewise smoothly converted with ethylmagnesium bromide in the presence of Ti(OiPr)4 to provide the corresponding bis (cyclopropanol) s [71,78]. 

A mixture of 9.5 g pyrrolyl-2-aldehyde, 29.2 g dimethyl-succinate and NaH (9.6 g of 50% suspension in oil) in 100 ml benzene is stirred at room temperature 6 hours, cooled and carefully acidified with glacial acetic acid. Add water and ether and dry, evaporate in vacuum or work up (JACS 72,501 (1950), JCS 1025(1959)) to get ca. 17 g (80%) 3-methoxycarbonyl-4-(2 -pyrrolyl)-3-butenoic acid (I) (recrystallize-acetone-benzene). A mixture of 12 g (I), 7 g sodium acetate and 70 ml acetic anhydride is left overnight at room temperature with occasional shaking. Then gradually raise the temperature to 70-75° over 2 hours, maintain for 4 hours and work up (see JCS 1714(1955), 986( 1958)) to get ca. 8 g (60%) methyl-4-acetoxy-indole-6-carboxylate (II) (recrystallize-petroleum ether). If desired, this can be converted to 4-OH-indole-6-COOH and 4-methoxyindole-COOH as described in the ref. or decarboxylated as described elsewhere here. If the 1-methyl cpd. is used, 1-Me-indole results. 

Dimethylstibine, 3 68 Dimethylstibinic acid, 3 73 Dimethyl succinate, 23 419 Dimethylsulfide borane, 4 186 Dimethyl sulfide production, 15 17 Dimethyl sulfosuccinate, 23 535 Dimethyl sulfoxide (DMSO), 10 369, 782 15 493... 

Stobbe reaction org chem A type of aldol condensation reaction represented by the reaction of benzophenone with dimethyl succinate and sodium methoxide to form monoesters of an a-alkylidene (or arylidene) succinic add. shtob-3 re.ak shan ) stoichiometry phys chem The numerical relationship of elements and compounds as reactants and products in chemical reactions., st6i ke am-3 tre )... 

Other alkali/alkaline earth metal iodides either cleave esters less efficiently or form insoluble carboxylate salts and are therefore not as effective as Lil. Addition of Li and l" compounds capable of forming Lil under reaction conditions works as well as initially charging Lil (Table IV). The acetaldehyde producing step. Equation 17, is carried out with the cobalt-based catalyst. Since the carboxylate half of the ester is not involved with the cobalt center, any methyl ester which can be cleaved by Lil should also show activity. We have found that methyl isobutyrate, dimethyl malonate, methyl propionate, and dimethyl succinate yield acetaldehyde and the corresponding carboxylic acids in high yield under the same conditions utilized with methyl acetate. 

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