O-Chlorobenzoyl chloride

Figure 2. Catalytic activities of SO /ZrCK prepared by use of HiSOj ( ) and (NH4) S04 ( >) vs calcination temperature. Yield % of dichlorobenzophenone in acylation of chlorobenzene with o-chlorobenzoyl chloride at 403 K in 3 h.

Acylation of aromatics which had been known to be catalyzed only by AICI3 was found to be effectively catalyzed by solid superacids. As shown in Table 4, SO4 /ZrCL exhibited a high activity for the acylation of chlorobenzene with o-chlorobenzoyl chloride in the liquid phase. The yield is 100% at 406 K in lOh, while the yields over H-ZSM-5 and SiC -ALOj are 0 and 0.17%, respectively [9]. 

If the mixture be kept at 125-140°, the reaction requires about thirty hours for completion. When about one-half of the necessary amount of chlorine has been added, the reaction mixture, if allowed to cool, sets to a colorless mass of an addition compound of the aldehyde and add chloride this on further chlorination yields o-chlorobenzoyl chloride. 

The oven-all yields are stated to be 13-20% from the acid chloride however, the directions are not clear. If the chloride of a dibasic acid is used, a diketone results. Thus, terephthalic acid chloride gives p-diacetylbenzene (15% over-all). o-Chloroacetophenone, a halo ketone, has been prepared from ethyl acetoacetate and o-chlorobenzoyl chloride... 

A solution of 165 g. (0.95 mole) of o-chlorobenzoyl chloride [Org. Syntheses Coll. Vol. 1, 155 (1941) ] in 300 ml. of dry benzene is added dropwise over a period of 2 hours to a stirred suspension of 170 g. (1.27 moles) of aluminum chloride and 400 ml. of benzene. (Hood.) The reaction mixture is allowed to stand at room temperature for another 5 hours and then is refluxed for 30 minutes. A mixture of ice and concentrated hydrochloric acid is added cautiously in small portions to hydrolyze the aluminum chloride. The benzene layer is separated, and the aqueous layer is extracted with fresh benzene. The combined benzene solutions are dried and distilled to give 175 g. (85.7%) of o-chlorobenzophenone, b.p. 181°/18-19 mm., m.p. 43-44°. 

The effect of several catalysts on the reaction between 80 20-TDI and a ten-molar excess of diethylene glycol adipate was also reported by Bailey et al. [153]. o-Chlorobenzoyl chloride was a slight retarder tertiary amines and cobalt naphthenate were catalytic. 

The old method632 of making acid halides from aromatic aldehydes and a halogen can be of preparative value when the aldehyde is more accessible than the carboxylic acid for instance, about 80% of o-chlorobenzoyl chloride is obtained when chlorine is led for about 15 h into vigorously stirred molten o-chlorobenzaldehyde (1 mole) at 140-160° (for details see Organic Syntheses).633... 

Obtained by total dealkylation of 5-tert-butyl-2 -chloro-2-methoxybenzophenone with aluminium chloride in benzene at 65-70° for 45 h (60-80%) [22], (73%) [9], Also obtained by Fries rearrangement of phenyl o-chlorobenzoate (SM) with aluminium chloride [23,897], at 140° for 30 min (32%) [485]. SM was prepared by heating o-chlorobenzoyl chloride with aluminium tris(phenoxide) in a water bath for 30 min [485],... 

Also obtained (poor yield) by reaction of o-chlorobenzoyl chloride with phenyl borate in the presence of aluminium chloride in tetrachloroethane at 100° (3%) [55],... 

Preparation by Fries rearrangement of phenyl o-chlorobenzoate (SM) with aluminium chloride at 140° for 30 min (56%). SM was obtained by heating o-chlorobenzoyl chloride with aluminium lris(phenoxide) in a water bath for 30 min [485]. 

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