Ar- -methylanilines

Perfluorobenzene undergoes Sf Ar reactions readily with dimethylarmne, aniline, N methylaniline [AS], piperidine, A/-tnmethylsilyliminotnmcthylphos-phorane [69], and bthinm aniUde [70], but the reactions are often accompanied by sigmficant amounts of di- or polysubstitubon However, with the lithium salt of A -tnmethylsilylanilme, only one fluorine atom in pcrfluorobenzeneis replaced [71] (equation 36)... 

Unlike unsubstituted and 3,4-disubstituted 1H-azepine-1 -carboxylates, which dimerize on heating, methyl 2-methyl-l//-azepine-l-carboxylate remains unchanged at 130 C, but on heating to 200°C ring contracts to Ar-(methoxycarbonyl)-2-methylaniline (64% mp 60°C).115 Similarly, the 4,5-dimethyl- and 3,6-dimethyl-l//-azepine-1-carboxylates, in which [6 + 4] dimerization is sterically retarded by the methyl groups, give only the A-arylurethanes. Methyl 2,7-dimethyl-1//-azepine-1-carboxylate is particularly stable and remains unchanged even after 24 hours at 200 C. 

N,2,3,4,5- or N,2,3,5,6-Pentanitro-N-methyl-aniline, mp 132° with decompn, 2453 cal/g, power by Trauzl test 151% of TNT, by BalMort 143% of TNT (Ref 11). According to Lothrop (Ref 11) the compd prepd by Blancksma (Ref 3) and described by him as N,Ar-hexanitro-N-methylaniline is actually one of the above-titled compds. Lothrop, however, was unable to distinguish between the two possible structures for Blancksma s compd Refs 1) Beil 12, 771, (372), [428] 1743 ... 

Aromatic amines are subdivided into primary amines, ArNH2, such as aniline, secondary amines ArNHR, in which the amino group has been monoalkylated and typified by TV-methylaniline (A-methyl-A-phenylamine, 3), and tertiary amines, ArNR such as A, A -dimethyl-aniline (Ar,ALdimethyi-A -phenylamine, 4). 

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