反应详情

A solution of the material prepared in Step A (169 gm, 1.19 mol) in CH2Cl2 (300 ml) was cooled in an ice-ethanol bath under N2 and chlorosulfonyl isocyanate (200 gm, 1.41 mol) was added via an addition funnel. The solution was allowed to rise to room temperature and stirred overnight. The reaction mixture was then diluted with Et2O and added to ice-cold NaHCO3 solution containing Na2SO3, keeping the solution below 5° C. during the addition. After the evolution of gas had ceased, the layers were separated and the aqueous layer was extracted with Et2O. The combined ether extracts were washed with H2O, brine and then dried over Na2SO4 before being evaporated to dryness. This gave a dark oil which was diluted with hexane (100 ml) and cooled in the freezer for 2 days. The low melting white solid which formed was filtered off and washed with cold hexane to give 79.2 gm of the title compound.

1. customto rise to room temperature
2. additionadded to ice-cold NaHCO3 solution
3. customthe solution below 5° C.
4. additionduring the addition
5. customthe layers were separated
6. extractionthe aqueous layer was extracted with Et2O
7. washThe combined ether extracts were washed with H2O, brine
8. dry with materialdried over Na2SO4
9. custombefore being evaporated to dryness
10. customThis gave a dark oil which
11. temperaturecooled in the freezer for 2 days
12. customformed
13. filtrationwas filtered off
14. washwashed with cold hexane