Acetyl chloride, reactant

A fixed-bed reactor for this hydrolysis that uses feed-forward control has been described (11) the reaction, which is first order ia both reactants, has also been studied kiaeticaHy (12—14). Hydrogen peroxide interacts with acetyl chloride to yield both peroxyacetic acid [79-21-0] and acetyl peroxide... 

Here AX is the acetyl compound (acetyl chloride or acetic anhydride), N is N-methylimidazole, I is the intermediate (presumably A -acetyl-A -methylimidazo-lium ion), X is the counterion (chloride or acetate), and ROH is the acetyl acceptor (alcohol or water). A general treatment of Scheme XXIII requires specification of the detailed nature of and k[ and is probably too complicated to be of practical use. However, several important special cases may arise from the operation of the ratio kxlk x, the behavior of apparent rate constants k /. and k, the relative magnitudes of k / and k, the relative concentrations of the reactants, the method of observation, and the nature of ROH. These cases are outlined in Scheme XXIV. 

Hydroxyl endgroups are usually titrated by acetylation or phthalylation in pyridine using an excess acetyl chloride, acetic anhydride, or phthalic anhydride. The excess of reactant is hydrolyzed and back titrated by aqueous sodium or potassium hydroxide. 

In a further run, the reactant concentration was doubled 0.395 mol acetyl chloride inTHF and 0.400 mol 1 n-butylamine and 0.400 mol EtjN inTHF were... 

All reactants should be pure and anhydrous. The tert.-butyl alcohol should be dried over quicklime and the dimethylani-line redistilled. Reagent grade acetyl chloride should be employed. 

The reactions of betaines 20a, n with acetyl chloride are unusual.84,97 The structure and composition of the products formed depend on the molar ratio of reactants. At equimolar amounts of the reactants in THF, the cyclic compound 54 is formed in 96-98% yield (Scheme 26). 

Twenty-five years ago the domestic supply of acetic acid came from the distillation of wood. This, in the form of calcium acetate, was reacted with acetyl chloride to produce acetic anhydride to satisfy the wants of the infant cellulose acetate rayon industry. Shortly thereafter a better process came on the scene utilizing the reactants sodium acetate, sulfur dichloride, and chlorine. 

Thus, the reaction of naphthalene with acetyl chloride to form acetonaphthone in C02 would require either prohibitively high pressures (> 600 bar) or extremely dilute (well less than 1 mol % reactants and... 

In a further run, the reactant concentration was doubled (see Table 1.10) [53] 0.395 mol 1 1 acetyl chloride in THF and 0.400 mol 1 1 n-butylamine and 0.400 mol l-1 Et3N in THF were processed in the second set-up with the straight tube at a total flow rate of2000 ml If1. Although extensive precipitation of Et3NHCl was observed, still the respective lumps were carried out of the tube. After 38 min of operation, no plugging was observed. 

Esterification is usually effected by refluxing the acid and alcohol with a small amount of sulfuric acid, hydrogen chloride, or arylsulfonic acid. The equilibrium is shifted to the right by an excess of one of the reactants or by removal of water either by azeotropic distillation or by means of a suitable drying agent. The necessity for continuous drying is eliminated when methylene or ethylene chlorides are used as solvents for the reaction. A small amount of an acid chloride such as thionyl chloride, acetyl chloride, or stearoyl chloride has proved superior to hydrogen chloride as a catalyst for certain esterifications at room temperature. ... 

Burton and Praill were the first to prqjare this ecies both by the interaction of perchloric acid with acetic anhydride and the metathetic reaction of sflver perchlorate with acetyl chloride , in a comprehensive study of acylation reactions. They did not attempt a characterisation of the compound and assumed that in acid solutions it existed in a fully ionised form. A few years later, Jander and Surawski followed the formation of acetyl perchlorate in acetic anhydride by measuring the electrical conductivity changes which took place when acetyl bromide was added to silver perchlorate or vice versa. In both titrations an inflection point was observed for a mixture of equimolar quantities of the two reactants indicating the formation of acetyl perchlorate. Moreover, it was clearly drown that this compound was at least partly ionised since its conductivity was higher than that of acetyl bromide. Avedikian and Commeyras characterised acetyl perchlorate by infrared and Raman spectroscopy both in acetic anhydride and carbon tetrachloride. They concluded that some ionisation was present but could not assess its extent. Molecular acetyl perchlorate was also detected. As far as we are aware, no other study of the structure and extent of dissociation of acetyl perchlorate in solution has been conducted. 

Rhone-Poulenc (now Rhodia) developed up to commercial scale an alternative process based on zeolite Beta [229,230] using acetic anhydride as reactant (Table 2.9). The original process used acetyl chloride in combination with 1.1 equivalents of AICI3 in a chlorinated hydrocarbon solvent, and generated 4.5 kg of aqueous effluent, containing AICI3, HCl, solvent residues and acetic acid, per kg of product. The... 

The N-acetyl-D,L-amino acid precursors are conveniently accessible through either acetylation of D,L-amino acids with acetyl chloride or acetic anhydride in a Schotten-Baumann reaction or via amidocarbonylation I801. For the acylase reaction, Co2+ as metal effector is added to yield an increased operational stability of the enzyme. The unconverted acetyl-D-methionine is racemized by acetic anhydride in alkali, and the racemic acetyl-D,L-methionine is reused. The racemization can also be carried out in a molten bath or by an acetyl amino acid racemase. Product recovery of L-methionine is achieved by crystallization, because L-methionine is much less soluble than the acetyl substrate. The production is carried out in a continuously operated stirred tank reactor. A polyamide ultrafiltration membrane with a cutoff of 10 kDa retains the enzyme, thus decoupling the residence times of catalyst and reactants. L-methionine is produced with an ee > 99.5 % and a yield of 80% with a capacity of > 3001 a-1. At Degussa, several proteinogenic and non-proteinogenic amino acids are produced in the same way e.g. L-alanine, L-phenylalanine, a-amino butyric acid, L-valine, l-norvaline and L-homophenylalanine. 

The preparation of MA -diethylacetamide is a standard acylation reaction. The reactants, acetyl chloride and diethylamine, have been prepared in previous parts of this problem. 

In the simplest form of the Abramov reaction, the phosphorus-containing reactant is hypophosphorous acid (phosphinic acid) or an ester thereof, and in the reactions between the acid and formaldehyde or benzaldehyde the initial product is the phosphinic acid 144 (R = H or Ph.). However, the reaction can proceed further to give the bis(l-hydroxyalkyl)phosphinic acid (145 R = H or Ph) the latter (R = Ph) reacts readily with yet more benzaldehyde to give its benzylidene derivative, 5-hydroxy-2,4,6-triphenyl-1,3,5-dioxaphosphorinane 5-oxide (146 R = Ph). When acted on by a second mole of cyclohexanone in the presence of acetyl chloride, (l-hydroxycyclohexyl)phosphinic acid (147) gives the novel phosphinic chloride 148, characterized as the free acid 149 following ready hydrolysis A reaction between a phosphinic acid (150) and a second (non-identical) carbonyl compound leads to an unsymmetrical phosphinic acid (151). Esters of symmetrical 1, r-dihydroxy-substituted phosphinic acids are preparable from hypophosphite esters, H2P(0)0R ". ... 

Reference has also already been made (Chapter 2, Section A.7) to the reaction which takes place between cyclohexanone and PhPCl2, and through which (1-chlorocyclo-hexyl)phenylphosphinic acid was obtained as an illustration of this synthetic route to a (1-chloroalkyl)phosphinic acid. Mixtures of the same reactants which also contain water or an alcohol or a mixture of cyclohexanone, acetyl chloride and phenylphosphonous acid yield the isomeric (l-hydroxycyclohexyl)phenylphosphinic chloride 230 ". The same compound was also formed when a 1 1 mixture of phenylphosphonous dichloride and phenylphosphonous acid (phenylphosphinic acid) was allowed to interact with cyclohexanone, no addition occurring between the acid and the ketone in the absence of the PhPCl2. The formation of230 was therefore depicted as the addition of the cyclohexanone... 

If optimum yields of acetyl chloride are desired, it appears that the reactants of Eq. (2) should first be mixed at low temperature and then heated to distill off acetyl chloride and hydrogen chloride. 

There is a great deal of difierence in the reactivity of different acid chlorides thhse derived from aromatic aCMs react much more slowly than those from aliphatic acids, and aryl sulfonyl chlorides react even more slowly. Thus, when benzoyl chloride is dissolved in an excess of ethyl alcohol and kef>t at 0 G, 4 hr is required for complete reaction, but acetyl chloride reacts practically instantly. To speed up the reaction of a sluggish acid chloride, the mixture may be heated, or the Schotten-Bauihann method may be used [Reaction (17)], i.e., the alcohol or phenol is mixed with 10 or even 25 per cent sodium hydroxide solution, and the acid chloride is added slowly with dgorous agitation, while the temperature of the mixture is kept at or below 0°G. Instead of aqueous alkali, anhydrous tertiary amines may be used. The cold reactants are mixed, but the mixture may be heated later. 

All the reactants e.g., benzene, aluminium chloride and acetyl chloride must be of highest purity so as to obtain better yeild and pure product. 

Sulphonedi-imines are sufficiently nucleophilic to displace halogen from reactive halides. Thus, reaction with CICN in the presence of triethylamine afforded the mono- or bis-cyano-derivative depending on the molar ratio of reactants used. The bis-cyano-derivative (119) was not sufficiently nucleophilic to form salts in the presence of acid. Acid hydrolysis afforded the bis-amide, and treatment with acetyl chloride in aqueous acetonitrile... 

With Mel or dimethylsulfate, the methyl derivatives are prepared with acetyl chloride-Cnl or the Weinreb amides, the ketones with methyl chloroformate, the methyl esters and with dialkyl oxalate, the a-oxo esters. Alkyl long-chain derivatives are better prepared by lateral (benzylic) metalation (see Section 26.7). Besides, aryllithiums may undergo transmetalation to afford a large panel of organometaUic species (Li Zn, Cu, Sn, Si, B, etc.), key reactants for transition metal-catalyzed reactions. The cross-conpling of aryllithium reagents with alkenyl triflates in the presence of the commercially avaUable catalytic system [Pdjfdbaljl/DavePhos] was recently reported [40]. 

Esterification of OH groups in methylol cellulose was studied. Ultimately, we wished to add long graft-like chains to the cellulose, so acid chlorides were the reactants of choice. Acetyl chloride was used as a model reactant. Here, DMSO cannot be used as a solvent because of its reactivity with acid chlorides. Esterifications were carried out by two methods, one involving direct reaction of acetyl chloride with methylol cellulose in DMF/LiCl using pyridine as acid acceptor. The pyridine was probably not necessary, though its equilibrium involvement with the acid chloride caused no apparent problem. 

Acetyl chloride in acetic acid added dr op wise during 10 min. to a stirred and refluxing mixture of 3-amino-l,2,2-trimethyl-4-thiocarbamoyl-3-pyrroline hydrochloride in acetic acid, and refluxing continued 45 min. 6,7-dihydro-2,6,7,7-tetramethyl-5H-pyrrolo[3,4-d]pyrimidine-4-thiol. Y 76%. F. e. and reactants s. J. F. Cavalla, N. E. Webb, and J. A. D. Willis, Soc. (G) 1967, 698. 

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