Tert-Butyl alcohol esterification

The synthesis of long-chain fatty acid esters of carbohydrates is inherently more demanding. It was found that glucose did not react with vinyl laurate in a pure ionic liquid medium, but in biphasic tert-butyl alcohol/[BMIm][PF6], glucose could be acylated by the vinyl esters of O, 2-Cu, fatty acids. The best results were obtained with CaLB, which was twice as active as TIL, and the selectivity for acylation at C-6 was high [114]. The esterification of glucose with palmitic acid, which is, in an industrial context, to be preferred over transesterification, has recently been demonstrated in tert-butyl alcohol/[BMIm][PF6] medium [115]. 

IH-pyrazole, 3,5-dimethyl-l//-pyrazole and lH-pyrazole-3,5-dicarboxylic acid were purchased from Aldrich Chemical Co. 3,S-Diphenyl-ltf-pyrazole is also a commercially available product (Lancaster Synthesis). Dimethyl-1 H-pyrazole-3,S-dicarboxylate has been obtained as described in ref. 6, di-tm-butyl-lH-pyrazole-3,5-dicarboxylate has been prepared from the corresponding acyl chloride by esterification with tert-butyl alcohol in 1,2-dichloroethane in the presence of triethyl amine. 

Cirin-Novta et al. (2006) have carried out the synthesis of esters of natural petroleum acids of the naphthenic type in presence of microwave irradiation under the conditions of acid catalysis with various alcohols like methanol, ethanol, -butanol and tert-butyl alcohol. The esters of the naphthenic acid were prepared imder microwaves irradiation by using naphthenic acids with sulfuric and /7-toluenesulfonic acid. The yield of naphthenic esters from 31.25 to 88.90% was achieved, which was dependent on the catalyst and the steric and nucleophilic properties of the alcohols. It was also found that the esterification time was reduced from 6-10 h to 5 min in microwaves. 

ESTERIFICATION OF HINDERED ALCOHOLS tert-BUTYL p-TOLUATE, 51, 96 Esters, from diazoketones and organoboranes, 53, 82 Esters, a-deuterio-, 53, 82 Esters, y [Pg.59]

Esterification of linalool requires special reaction conditions since it tends to undergo dehydration and cyclization because it is an unsaturated tertiary alcohol. These reactions can be avoided as follows esterification with ketene in the presence of an acidic esterification catalyst below 30 °C results in formation of linalyl acetate without any byproducts [71]. Esterification can be achieved in good yield, with boiling acetic anhydride, whereby the acetic acid is distilled off as it is formed a large excess of acetic anhydride must be maintained by continuous addition of anhydride to the still vessel [34]. Highly pure linalyl acetate can be obtained by transesterification of tert-butyl acetate with linalool in the presence of sodium methylate and by continuous removal of the tert-butanol formed in the process [72]. 

Olefins add anhydrous acetic acid to give esters, usually of secondary or tertiary alcohols propylene [115-07-1] yields isopropyl acetate [108-21 -4] isobutylene [115-11-7] gives tert-butyl acetate [540-88-5]. Minute amounts of water inhibit the reaction. Unsaturated esters can be prepared by a combined oxidative esterification over a platinum group metal catalyst. For example, ethylene-air-acetic acid passed over a palladium—lithium acetate catalyst yields vinyl acetate. 

The interest of chemists in this topic originated in two findings reported more than a century ago that exposed the influence of solvents on the rate of esterification of acetic acid by ethanol, estabhshed in 1862 by Berthelot and Saint-Gilles, and on the rate of qua-temization of tertiary amines by alkyl halides, discovered in 1890 by Menschutkin. In his study, Menschutkin found that even so-called inert solvents had strong effects on the reaction rate and that the rate increased by a factor about 700 from hexane to acetophenone. Subsequent kinetic studies have revealed even higher sensitivity of the reaction rate to the solvent. Thus, the solvolysis rate of tert-butyl chloride increases 340,000 times from pure ethanol to a 50 50 v/v mixture of this alcohol and water," and by a factor of 2.88x10 " from pentane to water. Also, the decaiboxylation rate of 6-nitrobenzisoxazol 3-carboxylate increases by a factor of 9.5x10 from water to HMPT. ... 

The alcoholysis of halo[ C]acetyl halides is one of the standard methods for the preparation of low molecular weight alkyl chloro- and bromo[ C]acetates . Other methods comprise the esterification of the free haloacids with diazomethane or -ethane (methyl/ethyl halo[ C]acetates) , with the respective primary alcohol in the presence of HCl gas or with 1,3-dicyclohexylcarbodiimide and 4-pyrrolidinopyridine (tert-butyl and benzyl halo[ C]acetates) . ... 

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