N-Boc-hydroxylamine is used in the preparation of azridines by cycloaddition of azides with nitroso Diels-Alder adducts. It acts as a reagent for the synthesis of hydroxylamine derivatives t-butyl-N-(acyloxy)carbamates and N,O-diacylated N-hydroxyarylsulfonamides.
A suspension of NH2OH·HCl (9.7 g, 140mmol) and K2CO3 (9.7 g, 700 mmol) in Et2O (60 mL) and H2O (2 mL)was stirred for about 1 h at r.t. with evolution of CO2 gas. A solution of Boc2O (20.0 g, 92 mmol) in Et2O (40 mL) was then added dropwise at 0 °C, and the suspension was stirred at r.t for 12 h. The organic phase was decanted, and the solid was washed with Et2O (3 × 30 mL). The combined organic layers were concentrated, and the residue was recrystallized from cyclohexane/toluene to afford the desired product tert-butyl N-hydroxycarbamate as a white solid.