Aryl succinates

EM is on the same scale as for aryl succinates (above), corrected for the increased pKt of substituted glutarates using P = 1.0... 

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],... 

In 2001, Deng and coworkers found that nucleophilic catalysts such as (DHQD)2AQN (11) can also affect the parallel kinetic resolution of racemic anhydrides by alcoholysis, that is, the two substrate enantiomers are converted into regioisomeric esters. A variety of monosubstituted racemic succinic anhydrides were converted in the presence of (DHQD)2AQN (11, 15-20 mol%) and allyl alcohol as a nucleophile to both regioisomeric hemiesters 49 and 50 with synthetically reliable ee values (up to 98% ee) and yields (Scheme 11.26) [41]. The obtained regioisomeric 2-or 3- aryl succinates could be converted to the P- and a-aryl-y-butylolactones, which constitute valuable synthons for various pharmaceuticals. 

In the same area, the group has reported the DKR of 2-oxo-3-aryl-succinates by L-proline-catalysed aldol addition of acetone in acetonitrile at room temperature, providing the corresponding products in good yields with diaster-eoselectivities of up to 74% de and high enantioselectivities of up to 99% ee (Scheme 2.104). " ... 

The aryl succinates (94) undergo smooth photo-Fries rearrangements leading to the enol lactones (95). 

V-Alkyl or A/-aryl succinimides can be prepared from the corresponding amines (107) or from succinic anhydride, ammonia, and the corresponding alcohol (108). Succinimides are also obtained by vapor-phase hydrogenation of the corresponding maleimides ia the presence of a catalyst (109). 

An interesting application of this reaction was the use of macro-molecular anhydrides, namely, styrene-maleic anhydride or vinyl acetate-maleic anhydride copolymers in the presence of perchloric acid as catalyst, these copolymers acylate mesityl oxide or d rpnone to macromolecular pyrylium salts which, with aryl substituents, are fluorescent.No crystalline products could be obtained from succinic anhydride because of the solubility and ease of decarboxylation. 

Diacyl or diaroy] peroxides (36, R- alkyl or aryl respectively) are given specific coverage in reviews by Fujimori,141 Bouillion et c//.,14 and Hiatt.14j They are sources of acyloxy radicals which in turn are sources of aryl or alkyl radicals. Commercially available peroxides of this type include dibenzoyl peroxide (BPO), didodecanoyl or dilauroyl peroxide (LPO), didecanoyl peroxide (42) and succinic acid peroxide (43). 

An amine-terminated polyoxyalkylene having an average molecular weight from about 600 to about 10,000 can be acylated with a succinic acylating agent (e.g., hexadecenyl succinic anhydride or a Diels-Alder diacid) obtained from an unsaturated fatty acid [628,629] similarly, alkyl-aryl sulfonate salts [1319] can be used in lubrication. 

Ammonium salts of alkenyl succinic half-amides have teen described for use as corrosion inhibitors in oil and gas production technology to combat corrosion by media containing CO2, H2S, and elemental sulfur [1366]. The inhibitor composition may contain a dispersing agent, such as a low molecular weight or polymeric anionic surfactant like an alkylsulfonic acid or an alkyl-aryl sulfonic acid. 

Aryl-substituted fulgides are the products of condensation of aromatic ketones with succinic anhydride, and form one of the oldest and most important groups of organic photochromic materials241. First discovered in the early part of the last century by Stobbe242, they are now well known to owe their photochromic behavior to reversible (conrotatory)... 

According to Thurston (702), the lower dibasic esters yield pure carbox5unonoguanamines so readily that this reaction is an excellent synthetic route, when confined to the lower esters. It has been apphed to 1-aryl- and alkyl-biguanides as usual, and to the alkali metal salts of half esters. The reaction involving diethyl malonate is represented below succinic acid esters (292, 699) react similarly. 

The photo-Fries rearrangement of aryl hydrogen (or methyl) succinates 267 leads to 4-(2-hydroxyaryl)-4-oxobutanoic acids (or methyl esters 268), which are readily cyclized to 5-(2-acetoxyaryl)-2(3//)-furanones (269) (Scheme 68). [189-191] Photolysis of 269 [191] or the analogous open-chain enol acetates [192,193] leads to chromones. 

Marans and co-workers used pentaerythritol trinitrate (81) to synthesize a number of aryl and alkyl esters, including the formate, propionate (84), oxalate, succinate, benzoate (85), 3,5-dinitrobenzoate (86), and ortho-, meta-, and para- (87) nitrobenzoate esters. The para-nitrobenzoate ester (87) has also been prepared from the nitration of pentaerythritol monobenzoate with mixed acid. ... 

More recently, we have discovered that Pd-JOSIPHOS complexes effectively desymmetrize a variety of succinic anhydrides in excellent yield and enantio-selectivity [Eq. (10.54)]. The reaction proceeds at ambient temperature in some cases and can deliver aryl and alkylzinc reagents with equal facility. For reasons that are unclear, the latter protocol requires a styrenic additive for high enantioselectivity ... 

A similar procedure was applied in the production of 3-(3-aryl-l,2,4-oxadiazol-5-yl)propanoic acids succinic anhydride was used instead of the acid chloride and the yields of these reactions were similar to the previous trials (46-62%). 

This procedure demonstrates a particularly effective method for controlling the relative and absolute stereochemistry of the aldol reaction. It is quite general in scope. Alkyl-, aryl, and a,6-unsaturated aldehydes all give good results. In addition to chiral propionates, a range of related aldol reactions may be carried out. For example, the analogous aldol reactions of thioalkyl, benzyloxy, or haloacetate, as well as succinate- and crotonate-derived carboximides, have been reported. 

The main group of methods for the preparation of a 1,2,4-oxadiazole ring is based on cyclization of amidoxime derivatives in the presence of acylating agents °. A surprisingly easy cyclization of O-benzoyl-/ -piperidinopropioamidoxime 247 to oxadiazole 248 in DMSO at room temperature was described (equation 107) . 3-(3-Aryl-1,2,4-oxadiazol-5-yl)propionic acids 250 were obtained by the reaction of amidoximes 249 with succinic anhydride under microwave irradiation or conventional heating (equation 108) °°. 

Sodium toluene dispersion of, 55, 65 Sodium p-toluenesulfinate, 57, 103 Spiro[4 n] alkenones, 58, 62 Spiro[cyclopentane-l,l -indene] 55, 94 Squalene, 56, 116 Squalene, 2,3-epoxy, 56, 116 Stannic chloride, 56, 97 Steroids synthesis, 58, 85 E Stilbene, 55, 115,58, 73 z-Stilbene, 58, 133 Styrene, 56, 35,58, 43 Styrene glycol, 55, 116 Styrene glycol dimesylate, 55, 116 Succinic acid, 58, 85 Succinic anhydride, 58, 85 Sucunimide, 56, 50, 58, 126 Succimmide, Vbromo, 55, 28, 56, 49 SULFIDE CONTRACTION, 55, 127 Sulfide, dimethyl-, 56, 37 SULFIDE SYNTHESIS, 58, 143,58, 138 SULFIDE SYNTHESIS ALKYL ARYL SULFIDES, 58, 143 SULFIDE SYNTHFSIS DIALKYL SULFIDES, 58, 143 SULFIDE SYNTHESIS UNSYMMETRI-CAL DIALKYL DISULFIDES, 58, 147 SULFONYL CYANIDES, 57, 88 Sulfur tetrafluoride, 57, 51... 

Vinylic and aryl halides can be used to vinylate or arylate carboxylic esters (but not ketones) by the use of NiBr2 as a catalyst.1463 However, ketones have been vinylated by treating their enol acetates with vinylic bromides in the presence of a Pd compound catalyst.1464 Also as in 0-94, this reaction can be used to close rings.1465 In one example of this, rings have been closed by treating a diion of a dialkyl succinate with a l,cu-dihalide or ditosylate,1466, e.g. ... 

Results of semiempirical calculations and deuterium exchange experiments indicate that the succinyl transfer from aryl enol succinates to the enolates of aryl ketones occurs by an addition-elimination mechanism and does not involve a retro-ene process.38... 

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