Reacción #560213

Ecuación de reacción

tert-butyl 3-(4-bromo-2-iodobenzyl)-3-cyanoazetidine-1-carboxylate

n-BuLi

THF

→

tert-butyl 6′-bromo-1′-oxo-1′,3′-dihydrospiro[azetidine-3,2′-indene]-1-carboxylate

Rendimiento 54.0%

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe reaction mixture was quenched with saturated NH4Cl
2. 2
   workup.ADDITIONdiluted with CH2Cl2
3. 3
   Secadodried over Na2SO4
4. 4
   OtroAfter the solvent was evaporated under reduced pressure
5. 5
   Otrothe residue was purified by chromatography on silica gel
6. 6
   Lavadoeluted with hexanes/ethyl acetate

Procedimiento

To a solution of tert-butyl 3-(4-bromo-2-iodobenzyl)-3-cyanoazetidine-1-carboxylate (4.2876 g, 8.99 mmol) in THF (120 mL) was added n-BuLi (2.5 Min hexane, 3.8 mL, 9.5 mmol) at −78° C. dropwise over 10 min under nitrogen. After 1 h, the reaction mixture was quenched with saturated NH4Cl, diluted with CH2Cl2, and dried over Na2SO4. After the solvent was evaporated under reduced pressure, the residue was purified by chromatography on silica gel eluted with hexanes/ethyl acetate to afford 1.7020 g (54%) of tert-butyl 6′-bromo-1′-oxo-1′,3′-dihydrospiro[azetidine-3,2′-indene]-1-carboxylate as a solid. LC-MS tR=1.90 min in 3 min chromatography, m/z 352, 354 (MH+), 337, 339 (MH+-15), 296, 298 (MH+-56); 1H NMR (400 MHz, CDCl3) δ 7.91 (m, 1H), 7.74-7.71 (m, 1H), 7.35 (d, J=7.9 Hz, 1H), 4.23 (d, J=8.2 Hz, 2H), 3.88 (d, J=8.2 Hz, 2H), 3.40 (s, 2H), 1.46 (s, 9H); 13C NMR (100 MHz, CDCl3) δ 204.38, 156.03, 150.44, 138.17, 137.24, 127.88, 127.29, 122.19, 80.05, 57.88, 44.70, 39.67, 28.35.

Fuente