Carbon tetrabromide → N-(4-Chloro-2-iodo-phenyl)-N-(4-azido-2-methylene-butyl)-methanesulfonamide

Temperature

-10 °C

To a stirred solution of N-(4-Chloro-2-iodo-phenyl)-N-(4-hydroxy-2-methylene-butyl)-methanesulfonamide obtained in Step A and triphenylphosphine (3.5 g) in dimethylacetamide (80 ml) at −10° C. under argon was added carbon tetrabromide (4.5 g). The reaction mixture was stirred at −10° C. for 45 min (a precipitate formed). Sodium azide (2 g) was added in one portion and the reaction mixture was stirred at 45° C. for 1 hour, cooled to room temperature, poured into water, extracted with ethyl acetate; the organic layer was washed with brine, dried (Na2SO4) and concentrated in vacuo. The residue was purified by silica gel chromatography (eluent cyclohexane:ethyl acetate 7:3) to afford N-(4-Chloro-2-iodo-phenyl)-N-(4-azido-2-methylene-butyl)-methanesulfonamide (1.96 g). 1H NMR (CDCl3, 400 MHz) 2.50 (m, 2H), 3.48 (m, 2H), 4.19 (d, J=12.0 Hz, 1H), 4.40 (d, J=12.0 Hz, 1H), 4.90 (s, 1H), 5.01 (s, 1H), 7.29 (d, J=8.5 Hz, 1H), 7.36 (dd, J=0.9H, 8.5 Hz, 1H), 7.92 (d, J=0.9 Hz, 1H).

1. customformed)
2. stirringthe reaction mixture was stirred at 45° C. for 1 hour
3. temperaturecooled to room temperature
4. extractionextracted with ethyl acetate
5. washthe organic layer was washed with brine
6. dry with materialdried (Na2SO4)
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel chromatography (eluent cyclohexane:ethyl acetate 7:3)

ORD record

ord-7edf1dd43a144f9fade48c4ac8d8940c

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08846907B2