Succinic acid, stmcture

Thiols and phosphines add to maleic anhydride to give a-thiosuccinic anhydrides (82) and phosphoranylidene—maleic anhydride adducts (83). Triethyl phosphite [122-52-1] reacts with maleic anhydride to give the yhde stmcture (23) (84). Hydrolysis of this adduct (23) leads to succinic acid... 

Mliphatic dibasic acids such as succinic acid, adipic acid, azelaic acid, and sebacic acids have also been used to make alkyd resins. Their linear chain stmcture lends higher flexibiUty and lower viscosity to the resin as compared to the rigid aromatic rings of phthaUc acids. 

Heat. When heated, succinic acid loses water and forms an internal anhydride with a stable ring stmcture. Dehydration starts at 170°C and becomes rapid at 190—210°C (25). Further heating of succinic anhydride causes decarboxylation and the formation of the dilactone of gamma ketopimelic acid (26) (eq. 1). The same reaction takes place at lower temperatures in the presence of alkaU. 

Succinic acid can be used in the flotation of cassiterite and some oxide minerals. Succinic acid is also called as butanedioic acid. The stmcture of succinic acid is as follows ... 

The influence of the stmcture of the acid could be clarified if extensive comparative studies of homologous acids would be performed in Pechini-type processes involving the same cations. From this point of view, the comparison of related acids [like malonic, HOOC-CH2-COOH, succinic, HOOC CH2-CH2-COOH, and glutaric, HOOC CH2-CH2-CH2-COOH), as well as acids and hydroxy acids [like succinic, HOOC-CH2-CH2-COOH, and hydroxysuccinic (malic), HOOC CH(OH) H2-COOH] is required. 

Besides LiBOB, other additives have been reported to protect the high voltage cathode and mitigate electrolyte decomposition, including LiDFOB [162], succinic anhydride [66, 122], 1,3-propane sultone [66], tris(hexafluoro- o-propyl) phosphate [127], tris(pentafluorophenyl) phosphine [156], 3-hexylthiophene [3], 1,3-propanediolcyclic sulfate [41], dimethylacetamide [13], triethyl(2-methoxyethyl) phosphonium bis(trifluoromethylsulfonyl)imide [13], glutaric anhydride [16], 4-(trifluoromethyl)-benzonitrile [55], and 1-propylphosphonic acid cyclic anhydride [ 160]. The stmctures of the additives that are not listed in the previous text are shown in Fig. 8. 

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