“…Substituted hydroxylamines can be prepared either from commercially available hydroxylamine derivatives through N-or O-derivatization, or from acylated hydroxylamines, oxime, or other nitrogen-containing compounds. N-Derivatization of hydroxylamines (Scheme 1) has been achieved by (a) nucleophilic substitution of highly nucleophilic hydroxylamine derivatives with a variety of primary and secondary alkylating agents; 51,52 (b) Mitsunobu reaction with alcohol; 51 (c) ringopening of epoxide by O-protected hydroxylamine; 51,53,54 (d) inter-or intramolecular 1,4-addition of hydroxylamines as well as N-or O-alkylhydroxylamines to activated carbon-carbon double bonds; 51,55 (e) intramolecular nucleophilic addition of hydroxylamine or hydroxamic acids to unactivated CvC bonds under thermal 51 or oxidative conditions; 56 (f ) reaction of hydroxylamines as well as N-or O-alkylhydroxylamines with aldehydes followed by reduction (NaBH 3 CN/AcOH or HCl) [57][58][59] or by carbon, oxygen, nitrogen or phosphorous nucleophile addition to oxyiminium intermediates; 51 (g) Pd(0)-catalysed three-component cascade reactions of allene and halides or triflates with protected hydroxylamines. 60 O-Derivatization of hydroxylamines (Scheme 2) is usually performed through (a) Mitsunobu reaction between alcohol and PhthNOH; [61][62][63] (b) nucleophilic substitution of bromide, 12,14,[64][65][66] iodide, 67 α-bromoesters [68][69][70] tosylate, 71 or mesylate 57,72,73 by PhthNOH, BocNHOH, BocB(Me)OH, BzNHOH, CF 3 CONHOH; (c) reaction of tertiary alcohol with stoichiometric BF 3 •Et 2 O and PhthNOH; 74 (d) alkoxide amination with 3,3′-di-tert-butyloxaziridine 75 or 3-trichloromethyloxaziridine; 76 and (e) Cu(I)/PhI(OAc) 2 -catalyzed 1,2-dihydroxylamination of alkenes.…”