Chlorobenzene Chlorobenzoic acid

Chlorobenzene, electrostatic potential map of, 565 13C NMR absorptions of, 536 phenol from, 575 p-Chlorobenzoic acid, pKa of, 760... 

Similarly, interphase catalysis permits carbonylation of haloaryls and halovinyls by NaCo(CO)4 with CO in water. The reaction proceeds according to S l mechanism and leads to high enough yields of carboxylic acids. Because C r-Cl bond is inert in these conditions, the direct and selective synthesis of chlorocarboxylic acids becomes possible. Thus, l-bromo-4-chlorobenzene gives 4-chlorobenzoic acid only (Brunet et al. 1983 Scheme 7.67). 

The following couples were tested p-chlorobenzonitrile/p-chloro-acetophenone, p-chloroacetophenone/p-chlorodiphenyl, p-chlorodiphenyl /chlorobenzene, p-chlorodiphenyl/p-chlorofluorobenzene, chlorobenzene /p-chlorotoluene, chlorobenzene/p-chloroanisole, p-chloroacetophenone/ methyl ester of m-chlorobenzoic acid, chlorobenzene/m-chlorotoluene, p-chlorodiphenylether/p-chlorotoluene, m-chlorodiphenylether/chloroben-zene, m-chlorodiphenylether/p-chlorotoluene, chlorobenzene/methyl ester of m-chlorobenzoic acid, chlorobenzene/p-bromoanisole, p-bromoaceto-phenone / p-chlorobenzonitrile, p-bromobenzonitrile / p-chloroacetophe-none, bromobenzene/p-chlorodiphenyl, m-bromotoluene/chlorobenzene, and p-chlorodiphenyl/p-bromotoluene. 

Details of the preparation of p-chlorotoluene are given in Expt 6.71, which also includes o-chlorotoluene, chlorobenzene, m-chloronitrobenzene and o-chlorobenzoic acid as examples of cognate preparations. 

High performance liquid chromatography (HPLC) and gas chromatography (GC) analysis of the products arising from m-CPBA and NHPI in acetonitrile at RT revealed the presence of m-chlorobenzoic acid as the main reaction product (< 90%) and chlorobenzene (< 10%) as by-product. Moreover, the same reaction in benzene solution at RT always led to m-chlorobenzoic acid as the main reaction product, whereas phenyl m-chlorobenzoate and m-chlorobiphenyl as by-products. 

Figure 6 Degradation of chlorinated aromatics, (a) Hydrolytic cleavage 4-chlorobenzoic acid, (b) Elimination of chloride after ring cleavage chlorobenzene, (c) Elimination of chloride before ring cleavage 2-chlorobenzoic acid.

Another example is the synthesis of " C-labelled DDT and once again the number of steps involved depends on the starting material. The first route starts with [ " C] /7-chlorobenzoic acid in order to synthesize [ " C]p-chlorbenzoyl chloride, which yields [ C]trichloromethyl / -chlorophenyl ketone. Next the [l- C]l-(p-chlorophenyl)-2,2,2-trichloroethanol reacts with anhydrous chlorobenzene and sulphuric acid (Fig. 2) [28, 29],... 

Chlorbenzene. See Chlorobenzene p-Chlorbenzoic acid. See p-Chlorobenzoic acid Chlorbenzol. See Chlorobenzene Chlorbufam CAS 1967-16-4... 

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