Benzoylating agent

Benzoyl chloride is an important benzoylating agent. In this use the benzoyl radical is introduced into alcohols, phenols, amines, and other compounds through the Friedel-Crafts reaction and the Schotten-Baumaim reaction. Other significant uses are in the production of benzoyl peroxide [94-56-0], benzophenone [119-61-9], and in derivatives employed in the fields of dyes, resins, perfumes, pharmaceuticals, and as polymerization catalysts. 

Benzoic anhydride is not manufactured on a large scale. Its primary use is as a benzoylating agent in the manufacture of pharmaceuticals and chemical intermediates. 

In our case, all the compounds obtained by transformation of the intermediate, phenylbenzoate, were primary products. This indicates that the following parallel reactions occurred on phenylbenzoate (1) the intramolecular Fries transposition generated o-hydroxybenzophenone, (ii) phenylbenzoate acted as a benzoylating agent on phenol, to yield p-hydroxybenzophenone (with also possible formation of the ortho isomer) and phenol and (iii) phenylbenzoate acylated a second molecule of phenylbenzoate to generate benzoylphenylbenzoates, with the co-production of phenol. 

Jacob et al/12] found that o-xylene can be benzoylated selectively to 3,4-dimethyl-benzophenone using zeolites as catalysts and benzoyl chloride as benzoylating agent. As shown in Scheme 4.2, zeolite H-BEA exhibits higher activity and selectivity for 3,4-dimethylbenzophenone (3,4-DMBP) than that of the other zeolite catalysts (H-ZSM-5, H-Y and H-MOR), due on the one hand to its stronger acid sites compared with the other zeolite catalysts and on the other hand to smaller pore openings (7.6 x 6.4 A and 5.5 x 5.5 A) than H-Y (7.4 x 7.4 A) zeolite, leading to a shape selectivity. In another article on benzoylation of toluene and naphthalene/101... 

Table 14.4 Screening of benzoylating agent for anisole with HY zeolite (Si AI = 27).

Reaction conditions molar ratio anisole benzoylating agent = 4, 2.5 v % of pov dered catalyst/ anisole, 125 °C, 4h. 

Since a precipitate of the metal chloride was obtained in every case, it is difficult to determine whether benzoylation of the compounds occurred when their chelate rings were partially or completely ruptured. Since benzoyl chloride did not react with either the copper or nickel chelate of diisobutyrylmethane in pyridine, it was assumed that the coordination positions, unoccupied by the donor atoms of the j8-diketone, were occupied by pyridine, thereby preventing the coordination of the benzoylating agent and subsequent benzoylation of the chelate. 

Benzoyltetrazole has proved to be a useful benzoylating agent for hydroxy groups in nucleosides.643 Some selectivity between primary and... 

Benzoyl triflate prepared from TfOH and Benzoyl Chloride is a mild and effective benzoylating agent for sterically hindered alcohols and acylative ring expansion reactions. The applications of TfOH in Koch-Haaf carboxylation, Fries rearrangement, and sequential chain extension in carbohydrates are also documented. Recent applications of TfOH in cyclization reactions have been published. ... 

Recently, a chiral benzoylating agent was developed by Kamik and Kamath [55] to resolve racemic amines. The chiral benzoylating agent, (S)-l-benzoyl-2-(a-acetoxyethyl) benzimidazole (51), was prepared by benzoylation of (S)-2-(a-... 

A preliminary report has been published on a promising new benzoylating agent, 2-benzoylthio-l-methylpyridinium chloride, and a general route to aryl esters involves treatment of aryl acids with phenols in DMF containing poly-phosphoric ester,simply obtainable from phosphorus pentoxide. 

Polymerisation catalyst, benzoylating agent. Can be used for synth. of aliphatic acid chlorides. Used to derivatise steroids and carbohydrates for chromatog. Fuming liq. d 1.22. Fp -1°. Bp 197°. 

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