O-Chloroacetanilide

Alachlor and metolachlor, two closely related preemergence o(-chloroacetanilide herbicides, have been reported to be carcinogenic (see ref. 5). Their... 

The facile addition of dichlorocarbenes to olefins under phase transfer conditions has also been observed with imines. The carbon-nitrogen double bond reacts with dichlorocarbene under conditions similar to those required for isolated alkenes. Thus, dichlorocarbene addition to C,N-diaryl substituted Schiff s bases afford good yields of l,3-diaryl-2,2-dichloroaziridines (Eq. 3.8). Hydrolysis of the C,N-diarylaziridines (IV) to the corresponding aryl-o -chloroacetanilides (V) is also reported (Eq. 3.9) and examples of both processes are recorded in Table 3.3. 

Hydrolysed by dilute acids and alkalis to aniline. It chlorinates more slowly than aniline to o-and p-chloroacetanilides. 

O Connell, K.M., Breaux, E.J., and Fraley, R.T. Different rates of metabolism of two chloroacetanilide herbicides in Pioneer... 

Phenyl o-radicals generated by reduction of aryl halides can also interact with an intramolecular alkene bond. Ihe method has been developed for the formation of dihydroindoles by reductive cyclization of N-allyl-2-chloroacetanilides. The results indicate the importance of a time interval between electron addition to give a radical-anion and the fragmentation of this species to give the active a-radical, The time interval allows the radical-anion to diffuse away from the electrode surface so that when the a-radical is foimed, it has time to cyclize before it can be reduced at the surface. 

If either the o- or -position is occupied, only one isomer is obtained transformation to the mefo-position does not occur. This is a standard method of preparation of acyl-amino-ketones, or by a further hydrolysis of amino-ketones. The tendency, illustrated in this reaction, of groups to wander from the amino group to the nucleus, is also shown in previous reactions and in the preparation of aminoazobenzene from diazoamino-benzene (Preparation 456), of sulphanilic acid from aniline sulphate (Preparation 292), of o- and p-chloroacetanilides from acetochloranilide (Preparation 328), of o- and p-toluidine from methylaniline hydrochloride, and of 1 2 4-aminodimethylbenzene (2 4-xylidine) from dimethylaniline hydrochloride. 

A new active substance of the chloroacetanilide herbicide group, previously known by the code number CGA 24 705, is metolachlor, 2-chloro-6 -ethyl-N-(2-methoxy-l-methylethyl)-o-acetotoluidide (metolachlor, 18), the herbicidal properties of which have been described by Gerber el al. (1974). 

Ammo-5,6,7,8-tetrabromo-4-tolyl-l(2/i/)-phthalazinone (72) underwent sub-stituted-alkylation by 2-chloroacetanilide to give 5,6,7,8-tetrabromo-2-[(iV-phenylcarbamoylmethyl)aniino]-4-tolyl-1 (2f/)-phthalazinone (72a) (reactants, EtOH, reflux, 4h 73% o, m, or -tolyl unspecified). ... 

The acid-catalyzed rearrangement of N-chloroacetanUide (Ingold, 1953, p. 604) to o- and -chloroacetanilide is worth mentioning not because the volume of activation throws light on the mechanism but because it emphasizes that basic chemistry must not be overlooked in interpretations of mechanism. The volume of activation in dilute aqueous solution (Harris and Weale, 1956) is 7-2 cm mole at 25°C and 8-1 cm mole at 35°C. It is likely that the reaction goes via the pre-equihbrium protonation of acetanilide, followed by the slow reaction of the protonated form with chloride ion... 

Synonyms 2-Chloro-6 -ethyl-N-(2-methoxy-1 -methylethyl) acet-o-toluidide a-Chloro-2 -ethyl-6 -methyl-N-(1-methyl-2-methoxyethyl)-acetanilide 2-Chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide 2-Chloro-N-(6-ethyl-o-tolyl)-N-(2-methoxy-1 -methylethylj-acetamide 2-Ethyl-6-methyl-1 -N-(2-methoxy-1 -methylethyl) chloroacetanilide Classification Chloracetanilide Empirical C1SH22CINO2... 

M.p. 91°. Prac. insol. cold HgO. Heat alone or warm with abs. EtOH —> o- and p-chloroacetanilides. 

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