Secondary amides reaction with, phosgene

Reactions.—Mono-A -alkylation of simple amides can be achieved by treatment of the corresponding amide methylols with trialkylaluminium reagents. Dipole-stabilized carbanions (166) can be formed from AW-dimethylbenzamides by treatment with s-butyl-lithium these react normally with a range of electrophiles leading to analogues of the N-methyl group. ° The little-studied A -ynamides (167) are accessible from secondary amides by sequential reaction with phosgene, a nucleophile, and potassium t-butoxide. ... 

Phosgene, as well as the easier to handle diphosgene (chloroformic acid trichloromethyl ester) or triphosgene (carbonic acid bis(trichloromethyl) ester) transform primary, secondary and tertiary amides and thioamides to chloromethyleneiminium chlorides (25 equation 15), whereby the reaction with thioamides is of broader scope and proceeds with fewer side reactions. The amide chlorides derived from primary and secondary amides can lose HCl, giving nitriles or imidoyl halides, respectively. /V-Sub-stituted formamides can be converted to isonitriles via amide halides. ... 

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