Hydrazonoyl halides, nitrile imines

The reaction of the 5-substituted-2-methyl-3(2-77)pyridazinone 383 with nitrile imine 384 generated in situ from the corresponding hydrazonoyl halide has been shown to afford 387 rather than 388. The formation of 387 is believed to proceed via the intermediacy of 385 (Scheme 33) <2000JST13>. 

The chromone imines (97), prepared from 3-formylchromone by treatment with p-anisidine or p-phenetidine, react smoothly with the nitrile imines (98), generated in situ from the corresponding hydrazonoyl halides in the presence of dry tnethylamine in chloroform to yield the 1 2 4-tri-... 

Nitrile imines are prepared in situ, generally by base-induced dehy-drohalogenation of hydrazonoyl halides (Scheme 5.44). 

SCHEME 5.44 Generation of nitrile imines of hydrazonoyl halides. 

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