Benzoyl chloride replacement

Now distil the contents of C by heating carefully over a gauze. A small initial fraction of unchanged thionyl chloride boiling at 78-80° comes over, and the temperature then rises rapidly to 194°. Directly this happens, stop the distillation, allow the condenser to drain thoroughly, and then replace G by the duplicate receiver. Run the water out of the condenser so that it acts as an air-condenser, and then continue the distillation. Collect the benzoyl chloride as the fraction boiling at 194-198°. Yield, 19 g. 

Assemble in a fume-cupboard the apparatus shown in Fig. 67(A). Place 15 g. of 3,5-dinitrobenzoic acid and 17 g. of phosphorus pentachloride in the flask C, and heat the mixture in an oil-bath for hours. Then reverse the condenser as shown in Fig. 67(B), but replace the calcium chloride tube by a tube leading to a water-pump, the neck of the reaction-flask C being closed with a rubber stopper. Now distil off the phosphorus oxychloride under reduced pressure by heating the flask C in an oil-bath initially at 25-30, increasing this temperature ultimately to 110°. Then cool the flask, when the crude 3,5-dinitro-benzoyl chloride will solidify to a brown crystalline mass. Yield, 16 g., i.e,y almost theoretical. Recrystallise from caibon tetrachloride. The chloride is obtained as colourless crystals, m.p. 66-68°, Yield, 13 g Further recrystallisation of small quantities can be performed using petrol (b.p. 40-60°). The chloride is stable almost indefinitely if kept in a calcium chloride desiccator. 

Bemoyl chloride may replace acetyl chloride as a class reagent it possesses the advantage that it is only very slowly decomposed by cold water and consequently may be employed for detecting alcohols even in aqueous solution. The reaction is usually carried out in aqueous solution containing sufficient caustic alkali to decompose any excess of benzoyl chloride into the water-soluble alkali benzoate (Schotten - Baumann reaction compare Section IV,52). The benzoyl esters formed are insoluble in water ... 

More useful than the preceding methods is cleavage of alkoxides by acetyl chloride or bromide. One, two, three, or four alkoxyls can be replaced by chloride or bromide. Benzoyl chloride gives poor yields, however. The tri- and tetrachlorides, which are stronger Lewis acids than mono- and dichlorides, coordinate with the alkyl acetate formed and yield distillable complexes (46,55,56). 

Chlorine can replace the hydrogen to produce benzoyl chloride. 

The second most important nucleophilic substitution in pyridazine A-oxides is the replacement of a nitro group. Nitro groups at the 3-, 4-, 5- and 6-position are easily substituted thermally with a chlorine or bromine atom, using acetyl chloride or hydrobromic acid respectively. Phosphorus oxychloride and benzoyl chloride are used less frequently for this purpose. Nitro groups in nitropyridazine A-oxides are easily replaced by alkoxide. The... 

Methyl a-D-mannopyranoside was treated in succession with p-toluene-sulfonyl chloride, carbonyl chloride, and benzoyl chloride, and, without isolating the intermediates, there was obtained in 37% yield methyl 4-0-l enzoyl-2,3-O-carbony 1-6-0-(p-tolylsulfonyl ) -D-mannoside. The tos-yloxyl group of the latter was replaced by iodine, and hydrogenation of the 6-iodo derivative in the presence of a nickel boride catalyst gave methyl 4-0-benzoyl-2,3-0-carbonyl-6-deoxy- -D-mannoside. Treatment of the latter with hydrogen bromide in acetic acid gave crystalline 4-0-benzoyl-2,3-0-carbonyl-6-deoxy-a-D-mannosyl bromide (8) (16). The... 

Leuco Methylene Blue, Basic Blue 3, or phenazine dyes are capped with a dye bearing acid chloride or chlorocarbonyl functionality. Normal procedures employed for the synthesis of benzoyl leuco Methylene Blue can be utilized except that a dye chloroformate (69) replaces the benzoyl chloride. 

A hydrogen attached to a pyridine or pyridine 1-oxide nucleus cannot be replaced directly by cyanide however, addition of cyanide to various quaternary salts constitutes an important class of reactions of synthetic importance. Before surveying these reactions in detail, the four main classes are outlined. In 1905, Reissert reported the first example, the reaction of quinoline with benzoyl chloride in aqueous potassium cyanide (Scheme 111) (05CB1603). This yielded a crystalline product, C17H12N2O, a Reissert compound (176) which afforded benzaldehyde and quinaldinic acid on acid hydrolysis (Scheme 111). Kaufmann (09CB3776) treated a 1 -methylquinolinium salt with aqueous potassium cyanide and observed 1,4-rather than 1,2-addition (Scheme 112), the Reissert-Kaufmann reaction. Reissert compounds are well known in the quinoline and isoquinoline series, but only rarely have even small yields been found in the pyridine series. On the other hand, cyanide ions add 1,4 with ease to pyridinium salts that have an electron withdrawing substituent at C-3. 

The Reissert-Henze and the Feely-Beavers-Tani reactions are considered together in this section because of their similarity. The former involves cyanation of acyloxy (formed in situ) (Scheme 113), and the latter alkoxy (Scheme 114), quaternary salts. The Reissert-Henze reaction is a facile, fairly general reaction for quinoline and isoquinoline AT-oxides (Table 19) with cyanation occurring a to the ring nitrogen. Certain substituents inhibit reaction, for example a 1-methyl group (equation 125), and others undergo replacement (Scheme 130) (81H(15)98l). Reaction of 1-methylisoquinoline 2-oxide with benzoyl chloride... 

Nitration of hydroxypropiophenone (7-1) followed by conversion of the phenol to its methyl ether by means of methyl iodide provides the intermediate (7-2) the nitro group is then reduced to the corresponding amine (7-3) by catalytic reduction. The newly introduced amine is then replaced by a nitrile group by successive conversion to the diazonium salt by means of nitrous acid followed by treatment with cuprous cyanide (7-4). Reaction with aluminum chloride removes the methyl ether to afford the ortho acylphenol (7-5). This is converted to the chromone (7-6) as above by reaction with benzoyl chloride and sodium benzoate. The nitrile is next hydrolyzed to the carboxylic acid (7-7) by means of sulfuric acid. The acid is then converted to its acid chloride by means of thionyl chloride and that treated with 2-(A -piperidyl)ethanol (7-8). There is thus obtained flavoxate (7-9) [8], a muscle relaxant whose name reflects its flavone nucleus. 

The vinylic fluorine of perfluoroisobutylene can be replaced with chlorine by using phosphorus oxychloride or benzoyl chloride however, somewhat different mixtures result from these two chlorinating agents [72] (equation 59). 

Of.B., 18,173 B., 12,10 9. 0.8., ,820 Ann., 29. 129 Perkin showed that the ester would not react with sodium alcoholate and benzoyl chloride,thus prov lng the absence of a replaceable hydrogen atom. 

Shvets and co-workers (298) have also prepared chiral 1-O-benzyl-myo-inositols by benzylation of the mannose orthoesters (427) and (428) with subsequent acidic hydrolysis. They were also prepared by partial benzylation of chiral l,2 5,6-di-<9-and 2,3 4,5-di-<9-cyclohexylidene-/ny< -inositols. These chiral monobenzyl ethers are potential intermediates for the synthesis of chiral inositol pentakisphosphates. Reaction of the orthoester (427) [299] with benzoyl chloride or diphenylphospho-chloridate in pyridine at 20 °C gave little reaction, whereas at 80 °C the orthoester group was replaced and both hydroxyl groups of the inositol derivative were acylated (or phosphorylated). 

A great variety of transformations of (N//-enamino)carbene complexes (Z)-97 become possible because of the presence of hydrogen at the nitrogen atom, which is readily replaced by other functional groups. C-Amino-methylenation of [2-(/V//-amino)ethenyl]carbene complexes (CO)5M = C(OEt) — CH = C(NHR)Ph (Z)-97 (M = Cr, W) with formamides HCO — NR2 (NR2 = NMe2, pyrrolidine, morpholine) in the presence of benzoyl chloride and triethylamine affords [2-amino-l-(iminoacyl)ethe-nyl]carbene complexes (CO)5M=C(OEt) - C[C(Ph)=NPh]=CHNR2 (E)-107 in 61-83% yield (Scheme 40). By elimination of carbon monoxide,... 

Benzoyl-p-aminophenylarsinie acid was first described in 1906, and prepared by the benzoylation of sodium p-aminophenylarsinatc, using benzoyl chloride and aqueous sodium hydroxide. Replacing the benzoyl chloride by o-, m- or p-nitrobenzoyl chloride. King isolated o -, m -, and p -mononitrobenzoyl-p-aminophenylarsinic acids respectively, which in turn were reduced to the corresponding amino-compounds in yields of 60 to 86 per cent. ... 

The evolution of HBr in the bromination reactions and the uptake of one bromine atom per ring indicate substitution at a secondary allylic carbon atom. The ease of oxidation and cross linking of the polymers and the presence of hydroxyl groups imply the intermediate formation of hydroperoxides on allylic carbon atoms. Treatment of the hydroxyl-containing polymer with benzoyl chloride indicates that the bulk of the hydroxyl groups are on secondary carbon atoms, since tertiary hydroxyl groups would tend to be replaced by chlorine. Although these results do not permit the elimination of structure B, it appears that the bulk of the structural units in the polycyclopentadiene corresponds to 1,2- addition (A). 

Primary and secondary amines possess replaceable amino hydrogen atoms. With acid chlorides (RCOCl) or anhydrides, (RCO)jO, they yield crystalline derivatives which are very useful in their separation and identification. Benzoyl derivatives are often preferred to acetyl derivatives because the former are less soluble and have higher melting points further, benzoyl chloride, unlike acetyl chloride, is not ea.sily hydrolyzed in water, and hence the acylation can be carried out in aqueous solutions. Tertiary amines do not react and therefore can be obtained unchanged. 

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