Chloride, benzoyl reaction with alcohols

Benzoyl chlorides, like other acyl chlorides, react readily with alcohols to form the corresponding esters (259). The reaction requires 19 h to be completed, and it has been studied in the analysis of carbohydrates, aminosugars, and glycosides (260). Because the preparation of acyl derivatives of monosaccharides is difficult, phenyldimethylsilyl chloride has been also investigated as an alternative label (261). After dissolving the analytes in dimethylformamide and addition of... 

Benzyl Chloride. Benzyl chloride is manufactured by high temperature free-radical chlorination of toluene. The yield of benzyl chloride is maximized by use of excess toluene in the feed. More than half of the benzyl chloride produced is converted by butyl benzyl phthalate by reaction with monosodium butyl phthalate. The remainder is hydrolyzed to benzyl alcohol, which is converted to ahphatic esters for use in soaps, perfume, and davors. Benzyl salicylate is used as a sunscreen in lotions and creams. By-product benzal chloride can be converted to benzaldehyde, which is also produced directiy by oxidation of toluene and as a by-product during formation of benzoic acid. By-product ben zotrichl oride is not hydrolyzed to make benzoic acid but is allowed to react with benzoic acid to yield benzoyl chloride. 

Acid chlorides were also shown to be reactive electrophiles. B-Allenyl-9-BBN affords tertiary bis-homopropargylic alcohols in satisfactory yields upon reaction with acetyl or benzoyl chloride (Eq. 9.23). 

The methylthiomethyl (MTM) group is a related alcohol-protecting group. There are several methods for introducing the MTM group. Alkylation of an alcoholate by methylthiomethyl chloride is efficient if catalyzed by iodide ion.9 Alcohols are also converted to MTM ethers by reaction with dimethyl sulfoxide in the presence of acetic acid and acetic anhydride10 or with benzoyl peroxide and dimethyl sulfide.11 The latter two methods involve the generation of the methylthiomethylium ion by ionization of an acyloxysulfonium ion (Pummerer reaction). 

The method described is adapted from the procedures of Kym 3 and Engelhardt, Latschinoff, and Malyscheff.4 Thio-benzoic acid has been prepared by the reaction of benzoyl chloride with potassium sulfide,4 hydrogen sulfide in pyridine,6 6 and magnesium bromide hydrosulfide.7 It is formed from dibenzoyl disulfide with potassium hydrosulfide,4 potassium hydroxide,4 8 and ammonia.9 It is also formed from dibenzoyl sulfide, from phenyl benzoate, and from benzoic anhydride with alcoholic potassium hydrosulfide.4 It has been obtained from dibenzoyl sulfide and hydrogen sulfide,10 carbon oxysulfide and phenyl-magnesium bromide,11 12 dibenzyl disulfide and sodium ethoxide,13 benzyl chloride and sulfur in the presence of potassium hydroxide,14 and benzylthiosulfuric acid and alkali.18 16... 

EXTENSIONS AND COMMENTARY N-Methyltryptamine (monomethyltryptamine, NMT) is an alkaloid that has been found in the bark, shoots and leaves of several species of Virola, Acacia and Mimosa. However, the major snuffs associated with these plant have been shown to also contain 5-MeO-DMT and are discussed there. NMT has been synthesized in a number of ways. One can react 3-(2-bromoethyl)indole with methylamine. NMT can be isolated as the benzoyl derivative from the methylation of tryptamine with methyl iodide followed by reaction with benzoyl chloride, with the hydrolysis of this amide with alcoholic KOH. It can also be synthesized from indole with oxalyl chloride, with the resulting glyoxyl chloride reacting with methylamine in ether to give indol-3-yl N-methylglyoxalylamide (mp 223-224 °C from IPA) which is obtained in a 68% yield, which is reduced to NMT to give the amine hydrochloride (mp 175-177 °C from ) in a 75% yield. The most simple and direct synthesis is the formamide reduction given above. 

A group from Spain patented a similar synthesis of risperidone (1) using similar synthetic transformations but in a different sequence (Scheme 2). Reaction of 2-aminopyridine with 2-acetylbutyrolactone in polyphosphoric acid at 160 °C afforded alcohol 15, which was hydrogenated to 16 and then converted to chloride 10 with thionyl chloride. Benzoyl piperidine 19 was prepared in a similar manner as in Scheme 1. In contrast to Scheme 1, 19 was alkylated with 10 prior to conversion to the 1,2-... 

Polysaccharide-based CSPs also exhibit a chiral recognition for alcohols and a large number of resolutions have been reported. Chiral alcohols can usually be directly resolved with hexane containing a small amount of an alcohol as the eluent. For aliphatic alcohols, which cannot be directly resolved, their resolution is often efficiently attained as phenylcarbamate or benzoate derivatives on OD (Figure 17).85 For example, 2-butanol and 2-pentanol are completely resolved with a very high selectivity on OD as their phenylcarbamates. The derivatization of alcohols to phenylcarbamates and benzoates can be easily achieved by the reaction with phenyl isocyanates and benzoyl chlorides, respectively. In most cases, the phenylcarbamates are better resolved than the benzoates. For chiral compounds bearing phenolic hydroxy groups, the addition of a small amount of an acid to an eluent is recommended to depress its dissociation. 

Fluoro-l-phenylpyrazole-4-carboxamides 304 have been formed by condensation of the 5-fluoro-l-phenylpyrazole-4-carboxylic acid 303 with amines (Equation 58) <2000EJ0823>. 4-Benzoyl-l-(4-nitrophenyl)-5-phenyl-l//-pyrazole-3-carboxylic acid 305 was converted via reactions of its acid chloride with alcohols or N-nucleophiles, into the corresponding ester or amide derivatives 306 (Equation 59) <2004CHE1039>. Resin-bound pyrazole-4-carboxylic... 

Reaction with benzoyl chloride causes no change in configuration about the chiral C of the alcohol. 

For the introduction of the benzoyl group (benzoylation) the procedure generally adopted is to use benzoyl chloride in dilute (10 per cent) alkaline solutions. Since benzoyl chloride reacts slowly with water at room temperature, the amino compound reacts fairly rapidly when shaken with it. The hydrogen chloride produced in the acylation is removed by the alkali. This method is known as the Schotten-Baumann reaction. The benzoyl derivatives nearly always crystallize well. The product is recrystallized to remove adsorbed and occluded impurities. If the derivative does not crystallize well, then a substituted benzoyl chloride is used, for example, p-nitrobenzoyl chloride. It will be recalled that for the characterization of the alcohols use was made of 3, 5-dinitrobenzoyl chloride. 

The reaction of amide chlorides with alcohols to yield alkoxymethyleneiminium salts, e.g. (91) and (92 Scheme 9), is important for the preparation of cations with bulky alkoxy groups, e.g. f-butoxy. These alcoholysis reactions demand the presence of salts with less nucleophilic anions in order to avoid dealkylation of the cations. This difficulty does not arise if the iminium hexachloroantimonates, which are obtained from the chlorides by addition of SbClj, are used for alcoholysis. A convenient route to / -unsubstituted salts (93 equation 54) is the alcoholysis of the formamide-benzoyl chloride adduct. The reaction of phenols with dimethylformamide chloride (27) affords aryloxymethyleneiminium salts (94 equation 55) which are hard to prepare by other methods. By addition of alkynols to the a-ha-loenamine (95) alkoxymethyleneiminium salts have been obtained (equation 56). ... 

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