Succinic derivatives

This cyclic peroxide, readily formed from succinate derivatives and peroxides, is claimed to be more stable than its molecular formula might indicate. It is, however, shock sensitive. 

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>. 

Trubiano, P., Succinate and Substituted Succinate Derivatives of Starch in Modified Starches Properties and Uses, Wurzburg, 0. B., Ed., CRC Press, Inc., Boca Raton, 1986, Chapter 9. 

The dicarboxylation of cyclic alkenes is a useful reaction. Only cxo-methyl-7-oxabicyclo[2.2.1]heptane-2,3,5,6-tetracarboxylate (121) was prepared from the cyclic alkene 120 using Pd on carbon and CuCl in MeOH at room temperature with high diastereoselectivity [89]. Methyl nitrite 37 is used for efficient oxidative carbonylation of alkenes to produce the succinate derivatives 122 [la,90]. It was claimed that the... 

The succinate derivative of inulin was further transformed into the corresponding reactive imidazolide by reaction with 1,1 -carbonyl-diimidazol (CDI, IV) ... 

Other useful modifications include acetylation, hydroxyethylation, hydro-xypropylation, cationic starches, succinate, and substituted succinate derivatives of starch. In starch-grafted copolymers, free radicals are initiated on the starch that then act as macroinitiators for the acryl or vinyl monomers. These products are used in firefighting fluids, electrolyte solutions for alkaline batteries, wound dressing, and so on. 

The use of a modified starch, corn starch sodium octenyl succinate derivative, for encapsulation of sea buckthorn kernel oil (containing polyunsaturated fatty acids, tocopherols, tocotrienols, plant sterols and carotenoids) by spray-drying was found to improve oil stability. Better protection was afforded when the starch encapsulant was stored in its glassy state (Partanen et al. 2002). Methylcellulose and hydroxymethy-oellulose in combination with soy lecithin enabled the production of 40% (W/W) fish oil powders with improved stability (Kolanowski et al. 2004). 

In the presence of CO, terminal alkenes are oxidized by PdCl2 to RCH(C1)CH2C0C1. When the reaction is made catalytic in palladium by the addition of CuCl2 and oxygen, and carried out in alcohols, the products are a, /3-unsaturated esters, /3-alkoxy esters, and, under some conditions, succinate derivatives (equation 87). Two mechanisms are possible for this reaction. In the first, an oxypalladation can produce a Pd-CH2-CH2-X species, which can undergo CO insertion into the Pd-C bond. Alternatively, an XCOPd species can form and add across the double bond. Loss of Pd-H can generate the a, /3-unsaturated ester, or a second carbonylation step can lead to succinate derivatives. 

Palladium chemistry dominates this area and the main problems are related to the way of reoxidizing Pd° efficiently. In general the reaction could be made catalytic in palladium by the use of an additional oxidant capable of reoxidizing the Pd to Pd . Typically, stoichiometric copper chloride, or catalytic amounts of copper chloride in the presence of air, have been used [28]. Other catalyst systems which have been described for bisalkoxycarbonylation of olefins to succinate derivatives are PdCl2 and butyl nitrite [29], Pd(OAc>2, O2 and benzoqui-none [30], and Pd(acac)2 and di-t-butyl peroxide [31]. So far, low TONs have delayed industrial applications. Because the reoxidation process is generating water, which causes side reactions, it is also necessary to add a water scavenger such as triethyl orthoformate in order to obtain good conversions and selectivities. 

Stobbe reaction The addition of a 1,4-diester, i.e. a succinate derivative, under basic conditions, to a ketone, followed by an acidic work-up, resulting in an a,(3-unsaturated ester and a (3,y-unsaturated carboxylic acid functionalities. 

The succinate derivatives described in Figure 5 were prepared by the methods of Purdie, Irvine, and Gillis (15). All Pfeiffer Effect studies with these environment compounds were carried out in water under the conditions described in Tables IV-VIII. 

Because of its symmetrical structure, a molecule of succinate derived from a 14C-labeled acetyl-CoA is converted into two forms of oxaloacetate, one with a labeled methylene group and one with a labeled carbonyl group. 14C-Iabeled CO, is not released until the third turn of the cycle when one-half of the original labeled carbon is lost (the carbonyl group derived from acetyl-CoA). The labeled carbon is further scrambled when succinyl-CoA is converted to succinate during the third and fourth turns of the cycle. 

Other groups also made attempts to separate local and systemic effects by integrating moieties susceptible to rapid, nonhepatic metabolism within the corticosteroid structure. One of the more successful attempts explored 17a-(alkoxycarbonyl)alkanoate analogs (35) of clobetasol propionate (144). Again, this can be considered as a hypothetical inactive metabolite—based approach, and a corresponding metabolite (35)(n. = 2, R = H) has indeed been shown to be inactive. Esters that were susceptible to rapid hydrolysis exhibited good separation of topical anti-inflammatory to systemic activity. The study also indicated the existence of an optimal volume for the 17a side chain. For example, the methyl succinate derivative (35) (/i = 2, R = methyl) showed as potent topical anti-inflammatory activity as clobetasol propionate, but a dramatically reduced thymolytic activity. Therefore, the cor-... 

Oxidative carbonylation of alkenes is a unique reaction of Pd(II). Three types of oxidative carbonylation to give -substituted acid derivatives 130, a, -unsaturated esters 132 and succinate derivatives 134 are known, which can be understood by the following mechanism. Palladation of alkenes with PdX2, followed by CO insertion, generates the acylpalladium intermediate 129 whose reductive elimination affords -substituted carboxylic acid derivatives 130 (path a). Reaction in alcohol in the presence of a base starts by the formation of the alkoxycarbonylpalladium 128. Carbopalladation of alkene with 128 generates 131. Then y3-H elimination of the intermediate 131 yields the a-unsaturated ester 132 (path b). Further CO insertion to 131 gives the acylpalladium intermediate 133 and its alcoholysis yields the succinate derivative 134 (path c). Formation of the jS-alkoxy ester 130 (X-OR) is regarded as nucleophilic substitution of Pd-X in 131 with alcohols. 

Trubiano PC., Succinate and substituted succinate derivatives of starch, in Modified Starch Properties and Uses, Ed. Wurzburg O.B., CRC Press, Boca Raton (USA), 1986, pp. 131-147. 

Fig. 2.6 Cross-linking, succinic and methacrylated derivative of dextran with a methacrylated and succinic derivative of poly(N-2-hydroxyethyl)-dl-aspartaniide (PHEA), PHM-SA...

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