The carbonyl oxygen may also be replaced by the oxime group,: N OH; thus the acids yield the hydroxamic acids, R C(OH): NOH, and the acid-amides the amidoximes, R C(NH 2): NOH.
The aldoximes are converted by the action of dehydrating agents into nitriles: RCH: NOH-->R C: N+H 2 0.
Chloraloxime, CC1 3 CH: NOH, is obtained when one molecular proportion of chloral hydrate is warmed with four molecular proportions of hydroxylamine hydrochloride and a little water.
Glyoxime, HON: CH CH: NOH, obtained from glyoxal and hydroxylamine, or by boiling amidothiazole with excess of hydroxylamine hydrochloride and water, melts at 178° C. and is readily soluble in hot water.
Acetoxime, (CH 3) 2 C:NOH, melts at 58-59° C. and is readily soluble in water.