Succinic anhydride, Table

Physical properties of the acid and its anhydride are summarized in Table 1. Other references for more data on specific physical properties of succinic acid are as follows solubiUty in water at 278.15—338.15 K (12) water-enhanced solubiUty in organic solvents (13) dissociation constants in water—acetone (10 vol %) at 30—60°C (14), water—methanol mixtures (10—50 vol %) at 25°C (15,16), water—dioxane mixtures (10—50 vol %) at 25°C (15), and water—dioxane—methanol mixtures at 25°C (17) nucleation and crystal growth (18—20) calculation of the enthalpy of formation using semiempitical methods (21) enthalpy of solution (22,23) and enthalpy of dilution (23). For succinic anhydride, the enthalpies of combustion and sublimation have been reported (24). 

Table 1. Physical Properties of Succinic Acid and Succinic Anhydride...

Commercial specifications of succinic acid and succinic anhydride are given in Table 2. 

Reactions with anhydrides afford interesting compounds having a carboxylic acid function (Table 26, entries 5 and 7 and Figure 40). It is notable that in the case of succinic anhydride, if the reaction is carried out at 25 °C, only one substitution occurs on the nitrogen atom, if the temperature is increased to 180 °C, there is a second substitution giving rise to a heterocyclic substituent (Table 26, entries 5-8). 

Variation of Equivalent Weight. In an attempt to produce more flexible coatings, the UPE A formulation was modified to increase the equivalent weight by substituting succinic anhydride for a portion of the maleic anhydride. These unsaturated polyesters were prepared by the same method as above and the compositions and their properties are summarized in Table II. 

Analysis of Table 7 reveals that the stability of the homochiral complexes is higher than that of the heterochiral ones, except in the cases with chiral succinic anhydrides. Similar results have been obtained by using (R)- and (A)- -naphthylethylamine as optically resolving reagents. ... 

Similarly, a variety of 2-alkyl and 2-aryl succinic anhydrides (58b-g) were resolved with good to excellent enantioselectivities (66-98% ee) (Table 11) [216],... 

To further test the functional purity of hydroxyl polymers prepared by the protected initiator and polymer route, two stage chain extensions of two polystyrene diols were carried out. The first stage involved conversion of the diols to acids with succinic anhydride the second stage involved chain extension with a diepoxide (Table III). If one assumes an overall conversion of 97-98%, a UP of 19 requires a functionality 1.93-1.95 based upon step-growth polymeri-... 

Comparison with in vivo procedures Although the FDNB procedure proved to be a suitable reference method, there is no doubt that all methods should be ultimately compared to in vivo procedures. For this reason selected samples were also analyzed by plasma amino acid and digestibility methods. Preliminary results ( Table II ) show that plasma lysine results correlated very well with results for lysine digestibility and FDNB lysine ( r =0.95 ), reasonably well with those for dansyl chloride lysine, succinic anhydride reactive lysine and dye binding lysine, but poorly with total lysine. Although the absolute values were in many cases very different, it is apparent that all methods except total lysine can be used to at least indicate the extent of lysine damage. 

A number of cyclic systems have produced bis-carboxonium dications (Table 1, entries 6-9). In the case of succinic anhydride (82), however, the product formed at — 80°C in FS03H-SbF5-S02 solution was the acyl-carboxonium dication (96, eq 26).37... 

An extensive study, summarized in Table VII, was carried out which established the effect of hydrochloric acid-succinic anhydride as combined activators on properties of boards made using maleic anhydride as the crosslinking agent. Data in Table VII is presented in two parts. In Fart A experiments are summarized in which either one or two of the three additives tab re used in the formulations in Part B all three additives were used. 

In this study a number of dibasic acids or their anhydrides were used. Results obtained using succinic anhydride and maleic acid, summarized in Table VIII, are particularly pertinent. When... 

Cyclization of Anhydrides. Instead of the acid chloride, an intramolecular anhydride of the type LXXIX may be used for cyclization by the Friedel-Crafts reaction (Table VII, examples marked by h ). This resembles the intermolecular acylation with succinic anhydride, and a similar procedure is generally followed. The product of ring closure is a keto acid LXXX. Nitrobenzene 9i 6,1120 is a generally effective solvent for the reaction sym-tetrachloroethane also may be used.121... 

TABLE 1. Selected polypropylene succinic anhydrides prepared using polypropylene containing an ene terminus and maleic anhydride. 

The hydroxy group of a Boc-protected Ser can be acylated with succinic anhydride and then coupled to an pMeBHA resin 21 (Table 2).f l The final peptide is released from the resin by ammonolysis. The hydroxy group of protected Tyr can be attached to the hydroxymethyl-PSty resin 4 using the Mitsunobu reaction.t w] jjj tjjjg case, treatment with liquid HE affords the corresponding peptide at the end of the synthetic process. 

Table 9.34 Molecular Weight Analysis of Polyisobutylene-Succinic Anhydride Copolymer Fractions...

The first step in the synthesis of 57, acylation of benzoin 58 with succinic anhydride 59, was performed under microwave irradiation in the presence of catalysts such as pyridine or 4-dime-thylaminopyridine (DMAP). Poor yields of 60 were obtained when this reaction was carried out in DMF or toluene at 80 to 110°C for 30 min (Table 25.6, entries 1 and 2). Trifluorotoluene was selected as a substitute solvent for the poorly absorbing toluene in another set of experiments. Under these conditions, yields from esterification of 58 were slightly higher (20 to 30%) than before but were still very low (Table 25.6, entries 3 to 6). A significant increase in yield was seen... 

Continuing with (13), all we have left is a 1,4-dicarbonyl relationship. The best strategy is to use the available 1,4 compound succinic anhydride in a Friedel-Crafts reaction (Table 25.1). 

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