Succinimide

The crude succinimide, which solidifies completely, amounts to about i68 g. The intermediate fraction is redistilled from a smaller flask, when a further quantity of about lo g. is collected over the range 275-289The crude succinimide is reciystallized from 95 per cent ethyl alcohol, employing i cc. of solvent for every gram of product. If the mixture is chilled to 0° for some hours before filtration and about 25 cc. of cold alcohol employed for washing the crystals, the first crop amounts to 163-164 g. (82-83 per cent of the theoretical amount). On concentrating the mother liquor to one-third of its volume, a second crop amormting to 4-5 g. can be secured (Note 2). The product melts at 123-125 and contains no water of crystallization. 

It is essential to employ a side arm of at least this diameter in order to avoid clogging by crystals of succinimide when this first passes over. 

A further small quantity of a less pure product can be obtained by evaporating the dark mother liquor to dryness and recrystaUizing the residue from fresh 95 per cent alcohol. 

Succinimide has usually been prepared by heating succinic acid in a current of ammonia or by distilling ammonium suc-cinate.1 2 

Submitted by Donald Stars and R. M. Hixom. Checked by John R. Johnson and H. B. Stevenson. 

The thermal decomposition of ammonium succinate gives a good yield of succinimide  

2-Aminotkiazole (III) Is prepared by the condensation of chloroacetalde-hyde (II) with thiourea (I). The reaction may be represented as follows  

Chloroacetaldehyde is unstable and lachrymatory it is therefore usually generated in situ by the action of water upon a(3-dichloroethyl ethyl ether  

2-Amino-5-methylthiazole. Suspend 76 g. of thiourea in 200 ml. of water in a 500 ml. three-necked flask equipped as in the preceding preparation. Stir and add 92-5 g. (80 ml.) of monochloroacetone (1) over a period of 30 minutes. The thiourea dissolves as the reaction proceeds and the temperature rises. Reflux the yellow solution for 2 hours. To the cold solution immersed in an ice bath add, with stirring, 200 g. of solid sodium hydroxide. Transfer to a separatory funnel, add a little ice water, separate the upper oil layer and extract the aqueous layer with three 100 ml. portions of ether. Dry the combined oil and ether extracts with anhydrous magnesium sulphate, remove the ether by distillation from a steam batli, and distil the residual oil under diminished pressure. Collect the 2-amino-5-methylthiazole at 130-133°/18 mm. it solidifies on cooling in ice to a solid, m.p. 44-45°. The yield is 84 g. 

Place a solution of 76 g. of thiourea in 200 ml. of warm water in a 600 ml. three-necked flask equipped with a dropping funnel, sealed mechanical stirrer and reflux condenser. Add 143 g. (122 ml.) of ap-dichloroethyl ethyl ether and heat the mixture under gentle reflux with stirring for 2 hours. As the reaction proceeds, the two layers gradually merge. To the cold solution add sufficient solid sodium hydroxide to liberate the 2-aminothiazole from its salt. Add ether to dissolve the product, dry the ethereal extract with anhydrous magnesium sulphate, and evaporate the ether. Recrystallise the crude 2-aminothiazole from ethanol the resulting yellow crystalline solid has m.p. 90°. The yield is 80 g. 

The reduction of 120 g. (128 cc., 1.76 moles) of furan requires about fifteen to twenty hours, depending upon the purity of the furan and the activity of the catalyst (Note 9). The yield of redistilled tetrahydrofuran is 114-1x8 g. (93-96 per cent of the theoretical amount). Since reduction is practically quantitative, the yield is determined largely by the care exercised in handling the volatile furan and tetrahydrofuran. 

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Dispersingagents, such as polyethylene polyamide succinimides or methacrylate-type copolymers, are added to motor oils to disperse low-temperature sludge formed in spark-ignition engines. 

They are formed by heating dibasic acids or their anhydrides with ammonia. The hydrogen atom of the NH group is acidic and can be replaced by a metal. Mild hydrolysis breaks the ring to give the half amide of the acid. See succinimide and phthalimide. 

To avoid these problems, refiners commonly use additives called detergents" (Hall et al., 1976), (Bert et al., 1983). These are in reality surfactants made from molecules having hydrocarbon chains long enough to ensure their solubility in the fuel and a polar group that enables them to be absorbed on the walls and prevent deposits from sticking. The most effective chemical structures are succinimides, imides, and fatty acid amines. The required dosages are between 500 and 1000 ppm of active material. 

Detergent and dispersant additives sulfonates, thiophosphonates, phenates, salicylates more or less overbased, succinimides. 

Derivatives of polyisobutylene (6. in Figure 9.1) offer the advantage of control over the molecular weight of the polyisobutylene obtained by cationic polymerization of isobutylene. Condensation on maleic anhydride can be done directly either by thermal activation ( ene-synthesis reaction) (2.1), or by chlorinated polyisobutylene intermediates (2.2). The condensation of the PIBSA on polyethylene polyamines leads to succinimides. Note that one can obtain mono- or disuccinimides. The mono-succinimides are used as... 

The third family (c. in Figure 9.1) less widespread, derived from the alkylphenols, offers as with the succinimides several possibilities of modification to the ratio of hydrophilic and lipophilic groups. Mannich s reaction of the alkyl-phenols also provides additives for lubricating oils. 

The role of detergent additives is to maintain clean injectors so as to insure good distribution of diesel fuel in the cylinder. The structure of these compounds is similar to that of detergents for gasoline engine admission systems. Commercialized compounds are from the succinimide family (see Figure 9.1). 

A -Bromosuccinimide (prepared by the action of bromine on succinimide at o in the presence of sodium hydroxide) is a valuable specific reagent for brominating olefines in the a-methylene position to the double bond without simultaneously adding bromine to this bond. For example, if A -bromosuccini-mide is represented by (C4H40t)NBr —... 

The substitution is best carried out by boiling A -bromosuccinimide with the olefine in carbon tetrachloride. Succinimide crystallises out from the carbon tetrachloride on cooling w hereas the brominated product remains dissolved in the carbon tetrachloride. 

Dissolve 22-8 g. of ethyl crotonate in 40 ml. of dry carbon tetrachloride and add 35 6 g. of. V-bromosuccinimide. Heat the mixture under reflux for three hours. Cool to o and filter off the succinimide which is insoluble in cold carbon tetrachloride. Now shake the filtrate with water in a separating funnel, separate and dry the carbon tetrachloride layer with sodium sulphate. Filter through a fluted filter-paper into a Claisen flask and distil... 

C) Imides. Both colourless solids succinimide is readily soluble, and... 

Fluorescein reaction. Fuse together in a dry test-tube o-i g. of succinimide, O l g. of resorcinol and 2 drops of cone. HjSOi, Cool, add water and then NaOH solution in excess. A green fluorescent solution is obtained. 

P-Naphthaldehyde. This preparation illustrates the use of -bromo-succinimide (Section VI.26) in the conversion of the readily available P-methylnaphthalene into 2-bromomethylnaphthalene and of the latter into p-naphthaldehyde by the Sommelet reaction. 

METHYL y-BROMOCROTONATE JV-Bromosuccinimide. Dissolve, with the aid of rapid mechanical stirring, 80 g. of pure succinimide (Section V,14) in a mixture of 150 g. of finely crushed ice and a solution of 32 g. of sodium hydroxide in 200 ml. of water contained in a litre beaker and cooled externally by ice. Immediately the imide has dissolved, continue the vigorous stirring and introduce 42 -5 ml. of bromine in one lot from a separatory funnel supported over the beaker it is essential that the bromine be instantly suspended in the solution. After stirring vigorously for 2 minutes, filter at the pump and... 

A more active product is obtained by the following slight modification of the above procedure. Dissolve the succinimide in a slight molar excess of sodium hydroxide solution and add the bromine dissolved in an equal volume of carbon tetrachloride rapidly and with vigorous stirring. A finely crystalline white product is obtained. Filter with suction and dry thoroughly the crude product can be used directly. It may be recrystallised from acetic acid. 

Methyl y-bromocrotonate. Mix 36 g. of iV-bromosuccinimide, 40 g. of methyl crotonate and 60 ml. of dry, redistilled carbon tetrachloride in a 500 ml. round bottomed flask. Reflux ou a water bath for 12 hours by this time all the sohd should have risen to the surface of the liquid. Filter off the succinimide at the pump and wash it with a little dry carbon tetrachloride. Remove the solvent on a water bath and distil the residue under reduced pressure, preferably from a Widmer flask (compare Figs. II, 24, 4-5). Collect the methyl y-bromocrotonate at 77-78°/8 mm. the yield is 31 g. 

Supplement 1953 3103-3241 Carbonyl compounds a-Pyrrolidone, 236. Tropinone, 259. Succinimide, 369. Isatin, 432. Phthalimide, 458. 

The next two bromination recipes use recyclable bromine donors that can be used over and over again. They are called dioxane and succinimide and are more common than you think. No, dioxane is not the same as the notorious dioxin but it is still pretty toxic. 

Replacement of the proton on nitrogen in succinimide by bromine gives N bromo succinimide a reagent used for allylic and benzylic brominations (Sections 10 4 and 1112)... 

Succinimides. Ethosuximide [77-67-8] C2H22NO2 (41) and the related succinknide, methsuximide [77-41-8] C22H23NO2 (42) are used in absence seizure treatment. Like the other anticonvulsants discussed, the mechanism of action of the succinirnides is unclear. Effects on T-type calcium channels and -ATPase activity have been reported (20). Ethosuximide has significant CNS and gastrointestinal (GI) side effect HabiUties (13). 

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