Alcohols, with acyl halides

SCHOTTEN-BAUMANN REACTION. Acylation of alcohols with acyl halides in aqueous alkaline solution. 

The alcoholysis of anhydrides (Reaction XVI) is similar in scope to the reaction of alcohols with acyl halides. The reaction is catalyzed by general esterification catalysts, but usually they are not needed unless the anhydride is unreactive or the di-ester (such as a phthalate) is the product sought. 

The reactions of Grignard reagents with different types of carbonyl groups yield a number of important functional groups. For example, reaction with formaldehyde yields 1° alcohols with higher aldehydes, 2° alcohols with ketones, 3° alcohols with esters, 3° alcohols with acyl halides, ketones with N,N-dialkylformamides, aldehydes and with carbon dioxide, carboxylic acids. 

Allylic silanes react with aldehydes, in the presence of Lewis acids, to give an allyl-substituted alcohol. In the case of benzylic silanes, this addition reaction has been induced with Mg(C104)2 under photochemical conditions. The addition of chiral additives leads to the alcohol with good asymmetric induction. In a related reaction, allylic silanes react with acyl halides to produce the corresponding carbonyl derivative. The reaction of phenyl chloroformate, trimethylallylsilane, and AICI3, for example, gave phenyl but-3-enoate. ... 

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]. 

Silyl ethers of aliphatic alcohols are inert towards strong bases, oxidants (ozone [81], Dess-Martin periodinane [605], iodonium salts [610,611], sulfur trioxide-pyridine complex [398]), and weak acids (e.g., 1 mol/L HC02H in DCM [605]), but can be selectively cleaved by treatment with HF in pyridine or with TBAF (Table 3.32). Phenols can also be linked to insoluble supports as silyl ethers, but these are less stable than alkyl silyl ethers and can even be cleaved by treatment with acyl halides under basic reaction conditions [595], Silyl ether attachment has been successfully used for the solid-phase synthesis of oligosaccharides [600,601,612,613] and peptides [614]. 

Because many more alcohols than alkyl halides are commercially available, the Mitsu-nobu reaction enables the synthesis of larger and more diverse compound arrays than alkylation with alkyl halides. A -AcyIsuIfonamides are strongly acidic and can be alkylated with diazomethane (Entry 6, Table 8.9) or trimethylsilyldiazomethane [137]. Resin-bound sulfonamides have been N-acylated by treatment with acyl halides, and N-carbamoylated by treatment with isocyanates [138]. 

Treatment of A and B with hydrogen over a nickel catalyst results in quantitative conversion of each compound to ferf-butyl alcohol. A reacts with acyl halides and anhydrides, whereas B is unaffected by these reagents. Treatment of 1 mole of A with excess methylmagnesium iodide in diethyl ether solution produces 1 mole of methane and 1 moie each of ferf-butyl alcohol and methanol. One mole of B with excess methylmagnesium iodide produces 1 mole of 2-methoxy-2-methylpropene and 1 mole of ferf-butyl alcohol. 

Aminothiazole, with acetaldehyde, 42 to 2-mercaptothiazoie, 370 4-Aminothiazole-2,5-diphenyl, to 2,5 di-phenyl-A-2-thiazoline-4-one, 421 Ammothiazoie-A -oxide, 118 2-Aminothiazoles. 12 acidity of, 90 and acrylophenone, 42 acylations of, with acetic acid. 53 with acetic anhydride, 52 with acyl halides, 48 with chloracetyl chloride, 49 with-y-chlorobutyrylchloride, 50 with 0-chloropropionylchloride, 50 with esters, 53 with ethy acrylate, 54 with indoiyl derivatives, 48 with malonic esters, 55 with malonyl chloride, 49 with oxalyl chloride, 50 with sodium acetate, 52 with unsaturated acyl chloride, 49 additions to double bonds, 40 with aldehydes, 98 alkylations, with alcohols, 38 with benzyhydryl chloride, 34 with benzyl chloride, 80 with chloracetic acid, 33 with chloracetic esters, 33 with 2-chloropropionic acid, 32 with dialkylaminoalkyl halides, 33 with dimethylaminoethylchloride, 35 with ethylene oxide, 34, 38... 

Various complex and low yield procedures for the preparation of acetylallene have been described oxidation of homopropargytic alcohol with chromium trioxide in sulfuric acid,11 mild acid hydrolysis of conjugated ethoxyenyne,12 reaction of propargyltrimethylsilane with acyl halide,13 flash vacuum thermolysis of 0-keto trimathylsilyl enol ether14 and cydoelimination of p-silylethyl sulfoxide.15... 

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