Glutaric diester

L. K. P. Lam, R. A. H. F. Hui, J. B. Jones, Enzymes in Organic Synthesis. 35. Stereoselective Pig Liver Esterase Catalyzed Hydrolyses of 3-Substituted Glutarate Diesters. Optimization of Enantiomeric Excess via Reaction Conditions Control , J. Org. Chem. 1986, 51, 2047 - 2050. 

As shown in Scheme 2.27, the prochiral center may be moved from the site of the reaction into the (3-position. Thus, chiral recognition by PLE [214-218] and a-chymotrypsin [219-222] is retained during the desymmetrization of prochiral 3-substituted glutaric diesters. Whole cells of Acinetobacter lowfii and Arthrobac-ter spp. have also been used as a source for esterase activity [223] and, once again, depending on the substitutional pattern on carbon-3, the desymmetrization can lead to both enantiomeric products. 

A number of examples of enantioselective hydrolysis of diesters (I and 2) of malonic and glutaric acids are given in Table I. 

Porcine liver esterase (PLE) gives excellent enantioselectivity with both dimethyl 3-methylglutarate [19013-37-7] (lb) and malonate (2b) diester. It is apparent from Table 1 that the enzyme s selectivity strongly depends on the size of the alkyl group in the 2-position. The hydrolysis of ethyl derivative (2c) gives the S-enantiomer with 75% ee whereas the hydrolysis of heptyl derivative (2d) results in the R-monoester with 90% ee. Chymotrypsin [9004-07-3] (CT) does not discriminate glutarates that have small substituents in the 3-position well. However, when hydroxyl is replaced by the much bulkier benzyl derivative (Ic), enantioselectivity improves significantly. 

The enzymatic synthesis of polyesters from activated diesters was achieved under mild reaction conditions. The polymerization of bis(2,2,2-trichloroethyl) glutarate and 1,4-butanediol proceeded in the presence of PPL at room temperature in diethyl ether to produce the polyesters with molecular weight of 8.2 x 10. Vacuum was applied to shift the equilibrium forward by removal of the activated alcohol formed, leading to the production of high molecular weight polyesters. The polycondensation of bis(2,2,2-trifluoroethyl) sebacate and aliphatic diols took place using lipases BC, CR, MM, and PPL as catalyst in diphenyl ether. Under the... 

Glutarimides.4 Sodium amide (3 equiv.) in liquid ammonia is the base of choice for conversion of glutaric acid diesters into glutarimides (45% yield in the case of glutarimide itself). 

Monoesters of symmetric dicarboxylic acids can be prepared either by monoesterification of a diacid [1] or by monosaponification of a diester. Dicarboxylic acids which can form five- or six-membered cyclic anhydrides are readily transformed into monoesters via these intermediates, but for diacids which cannot be converted into such cyclic anhydrides monosaponification of diesters seems to be more reliable than selective monoesterification. Monoesters or monoamides of succinic, maleic, glutaric, or related diacids can be rather unstable, because of the dose proximity of a carboxyl group (see Section 3.3). 

Pig Liver Esterase (PLE). This is the more used car-boxylesterase (carboxylic-ester hydrolase, EC 3.1.1.1, CAS 9016-18-6) which physiologically catalyzes the hydrolysis of carboxylic acid esters to the free acid anion and alcohol. PLE is a serine hydrolase which has been widely used for the preparation of chiral synthons and these applications have been fully reviewed. An active-site model for interpreting and predicting the specificity of the enzyme has been published. In the pioneering studies of the enzyme applications field, PLE was used for the chiral synthesis of mevalonolactone. Prochiral 3-substituted glutaric acid diesters... 

The synthesis has been reported of the D-homo-c-nor-derivative (132) from the keto-ester (129). Stobbe condensation of 2-(l-methoxycarbonylethyl)-4,5-benzindan-l-one (129) with dimethyl glutarate afforded an acid which on hydrolysis-decarboxylation and subsequent esterification provided the diester (130). Catalytic hydrogenation of (130), followed by base hydrolysis, gave the diacid (131), which on pyrolysis yielded the tetracyclic keto-derivative (132). ... 

In 1976, Dolby reported the preparation of the hydrindan 15 (Scheme IX) (23). Dimethyl pyruvic acid 45 was prepared according to the procedure of Ramage and Simonsen (28). The condensation of hippuric acid (43) and acetone yields tFfe oxazolone 44, which affords 45 upon treatment with concentrated hydrochloric acid. The Friedel-Crafts acylation of ethylene with glutaric anhydride afforded 5-oxo-6-heptenoic acid 46 in low yield (14-45 ). Base-catalyzed condensation of 45 with 46 gave the crude dibasic acid 47 in 79 yield. Treatment of 47 with excess diazomethane provided the diester 48 in quantitative yield. The esterification also can be accomplished in 90 yield with DBU and iodomethane (L. 0. Dolby, University of Oregon, personal communication, 1979). Base-catalyzed cyclization of 48 afforded 15 in 98 yield. 

The reaction mixture (2 g) was esterified at reflux with methanol (15 cm ) in the presence of 2 drops of concentrated H2SO4 to obtain the diacids in the diesters form. The products were analysed using a Hewlett Packard gas chromatograph equipped with a Carbowax 52 CB polar capillary column and a flame ionization detector assembled with a Shimadzu programmed and computerized Chromatopac CR6A. The reaction products consisted of adipic, glutaric, succinic and 6-hydroxycaproic acids, cyclohexanone, cyclohexanol and butyrolactone. 

The question of regiochemistry does not arise in the case of diesters. Diethyl succinate has been converted to the disilyl ketene acetal (59) in good yield. A number of glutarate esters (60) have been similarly transformed to (61). ... 

Diester solvents Mixtures of the methyl esters of succinic, glutaric and adipic acids. Paint will smell nice. 

Dibromo derivatives of succinic,548,581 glutaric,582 adipic,583 and pimelic acid584 are examples of compounds prepared by these methods. To obtain the diesters the crude a -dibromo dicarbonyl dihalides are treated with the required alcohol the preparation of diethyl 2,5-dibromoadipate by way of the crude dichloride is described as a typical example in Organic Syntheses.585... 

The reaction of the same reagent with a,[Pg.147]

The traditional synthesis of 1,2,3-trihydroxybenzene by decartx)xylation of gallic acid from natural sources has been superseded by the use of acyclic precursors. Dimethyl oxomalonate and dimethyl glutarate undergo cyclodehydration and tautomerism to give a diester product which uponhydrolysis decarboxylates to pyrogallol in about 65% yield (ref.3). 

Empirical C40H76O4 Formula C18H37OCOCHCHCOOC18H37 Uses Emollient lubricant conditioner Trade Name Synonyms Schercemol DISF [Scher http //www.scherchem.com, Chesham Chems. Ltd http //WWW. cheshamchemicals. co. uk] Diisostearyl glutarate Synonyms Pentanedioic acid, bis (16-methylheptadecyl) ester Definition Diester of isostearyl alcohol and glutaric acid... 

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