P Chlorobenzoic anhydride

This modification is illustrated by the preparation of p-chlorobenzoic anhydride from p-chlorobenzoyl chloride. 

Place a mixture of 17 -5 g. p-chlorobenzoyl chloride (1) and 50 ml. of dry pyridine (Section 11,47,22) in a loosely-stoppered 250 ml. flask and warm on a steam hath for 5 minutes. Pour the reaction mixture upon 100 g. of crushed ice and 50 ml. of concentrated hydrochloric acid. The anhydride separates out at once. When the ice has melted sufficiently, filter the mixture by suction. Wash the sohd with 15 ml. of methanol and then with 15 ml. of dry benzene. The yield of crude p-chlorobenzoic anhydride is 14 5 g. Recrystalhse from 250 ml. of dry benzene 13 g. of the pure anhydride, m.p. 192-193°, are obtained. 

B. p-Chlorobenzoic anhydride benzoic anhydride, p,p -di-ckloro-). A mixture of 17.5 g. (0.1 mole) of j -chlorobenzoyl chloride (Note 6) and 50 ml. (0.6 mole) of pyridine in a loosely stoppered 200 ml. flask is warmed on the steam bath for 5 min-... 

In the following we shall focus on heterogeneous acid-base reactions. One of the best known case studies is the reaction of crystalline benzoic acid with ammonia to form 1 1 ammonium salts [19, 20]. Crystalline p-chlorobenzoic anhydride reacts with gaseous ammonia to give the corresponding amide and ammonium salt [22] a similar reaction has been investigated in the case of optically active cyclopropanecarboxylic acid crystals [23]. 

Cl4H8CINO2, N-(p-Chlorophenyl)phthalimide, 40B, 106 C14H8CI2O2, Biphenyl-2,2 -dicarbonyl chloride, 44B, 80 C14H8CI2O3, p-Chlorobenzoic anhydride, 31B, 65 C14H8CI2O4, 4,4 -Dichlorodibenzoyl peroxide, 33B, 43 C14H9CIO4, 2-(4 Chloro-2 -hydroxybenzoyl)benzoic acid, 46B, 77... 

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