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From acyl halides reaction with alcohols

Tertiary alkyl azides can be prepared by stirring tertiary alkyl chlorides with NaN3 and ZnCl2 in 82 ° or by treating tertiary alcohols with NaN3 and CF3-COOH or with HN3 andTiCl4 or BF3. Acyl azides, which can be used in the Curtius reaction (18-14), can be similarly prepared from acyl halides, anhydrides, " esters, or other acyl derivatives. ° Acyl azides can also be prepared... [Pg.516]

Organopalladium intermediates are also involved in the synthesis of ketones and other carbonyl compounds. These reactions involve acylpalladium intermediates, which can be made from acyl halides or by reaction of an organopalladium species with carbon monoxide. A second organic group, usually arising from any organometallic reagent, can then form a ketone. Alternatively, the acylpalladium intermediate may react with nucleophilic solvents such as alcohols to form esters. [Pg.708]

Amides can be obtained from acyl halides, carboxylic anhydrides, or esters with amines or ammonia. The mechanisms of these reactions are very similar to the corresponding reactions of alcohols ... [Pg.822]

Among other reactions, the bis-metallated species (151) derived from nitroalkanes condense with dialkyl carbonates to give comp>ounds (152), in 60—80% yield, which can serve as precursors of both a-amino-acids and a-hydroxyamino-esters as well as a-keto-esters. Oxazolin-5-ones (153) can be alkylated at the 4-position by alkyl halides in hot DMF containing HMPA and ethyldi-isopropylamine. Yields are good (60—90%) for allylic, benzylic, and propargylic halides but otherwise poor (e.g. 32% with EtI) under these conditions acid hydrolysis of the products affords substituted a-amino-acids. Mesoionic l,3-oxazol-5-ones (154), obtained from imidoyl chlorides and acyl-tetracarbonylferrates, react with alcohols to give N-acyl-a-amino-acid esters. ... [Pg.130]

The primary and secondary alcohol functionalities have different reactivities, as exemplified by the slower reaction rate for secondary hydroxyls in the formation of esters from acids and alcohols (8). 1,2-Propylene glycol undeigoes most of the typical alcohol reactions, such as reaction with a free acid, acyl halide, or acid anhydride to form an ester reaction with alkali metal hydroxide to form metal salts and reaction with aldehydes or ketones to form acetals and ketals (9,10). The most important commercial application of propylene glycol is in the manufacture of polyesters by reaction with a dibasic or polybasic acid. [Pg.366]

Because of the special structural requirements of the resin-bound substrate, this type of cleavage reaction lacks general applicability. Some of the few examples that have been reported are listed in Table 3.19. Lactones have also been obtained by acid-catalyzed lactonization of resin-bound 4-hydroxy or 3-oxiranyl carboxylic acids [399]. Treatment of polystyrene-bound cyclic acetals with Jones reagent also leads to the release of lactones into solution (Entry 5, Table 3.19). Resin-bound benzylic aryl or alkyl carbonates have been converted into esters by treatment with acyl halides and Lewis acids (Entry 6, Table 3.19). Similarly, alcohols bound to insoluble supports as benzyl ethers can be cleaved from the support and simultaneously converted into esters by treatment with acyl halides [400]. Esters have also been prepared by treatment of carboxylic acids with an excess of polystyrene-bound triazenes here, diazo-nium salts are released into solution, which serve to O-alkylate the acid (Entry 7, Table 3.19). This strategy can also be used to prepare sulfonates [401]. [Pg.82]

There are several types of chiral derivatizing reagents commonly used depending on the functional group involved. For amines, the formation of an amide from reaction with an acyl halide [147,148], chloroformate reaction to form a carbamate [149], and reaction with isocyanate to form the corresponding urea are common reactions [150]. Carboxyl groups can be effectively esterified with chiral alcohols [151-153]. Isocynates have been used as reagents for enantiomer separation of amino acids, iV-methylamino acids, and 3-hydroxy acids [154]. In addition to the above-mentioned reactions, many others have been used in the formation of derivatives for use on a variety of packed and capillary columns. For a more comprehensive list, refer to References 155-159. [Pg.58]

Chiral lactones were synthesized by stereoselective reduction reactions with a carbohydrate auxiliary [178]. The benzyl protected 3,6-anhydro-a-D-glucopyranoside 279 was acylated with acid halide 280, and the product 281 was reduced with Zn(BH4)2 (Scheme 10.91). The alcohol 282 was obtained with a high diastereomeric excess (96 4). Cleavage from the auxiliary by... [Pg.492]


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Acyl halide reactions

Acyl with alcohols

Acylated alcohols

Alcohols acylation

Alcohols acylic

Alcohols reaction with acyl halides

Alcohols, with acyl halides

Halides from alcohols

Halides, acyl from alcohols

Reaction with acyl halides

Reaction with alcohols

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