Reaction #168699

Reaction equation

[5-(3-Bromo-phenyl)-5-methyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester

sodium azide

sodium ascorbate

(1R,2R)—N,N′-dimethyl-cyclohexane-1,2-diamine

→

title compound

[5-(3-Azido-phenyl)-5-methyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester

Solvents

water

ethanol

Conditions

Workup

1. 1
   ExtractionThe mixture was extracted with EtOAc
2. 2
   Washthe organic phase was washed with brine
3. 3
   Dryingdried with Na2SO4
4. 4
   Otherevaporated under reduced pressure
5. 5
   OtherThe residue was purified by chromatography on silica gel (cyclohexane/EtOAc=7:3)

Procedure

[5-(3-Bromo-phenyl)-5-methyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester (5.03 g, 12.67 mmol), sodium azide (1.647 g, 25.3 mmol), sodium ascorbate (0.125 g, 0.63 mmol), copper iodide (0.241 g, 1.27 mmol) and (1R,2R)—N,N′-dimethyl-cyclohexane-1,2-diamine (0.270 g, 1.90 mmol) were dissolved in ethanol (17.7 ml) and water (7.6 ml). The mixture was stirred under N2 at 90° C. for 4 h and then poured into 1M aqueous KHCO3 solution. The mixture was extracted with EtOAc, and the organic phase was washed with brine, dried with Na2SO4 and evaporated under reduced pressure. The residue was purified by chromatography on silica gel (cyclohexane/EtOAc=7:3) to yield the title compound.

Source