Those derived from aldehydes are known as aldoximes, those from ketones as ketoximes.
Ketoximes are usually rather more difficult to prepare than aldoximes, and generally require the presence of a fairly concentrated alkaline solution.
In order to arrive at the configuration of the stereoisomeric ketoximes, A.
On oxidation with chromic acid they yield dinitrohydrocarbons, and on reduction with hydroxylamine (in alkaline solution) or with potassium sulphydrate give ketoximes, RR': C: NOH (R.
Curtius), and with hydroxylamine ketoximes.