Sulfuric Acid → HCID 23657565, compound

Reaction equation

[F:1][C:2]1[CH:7]=[CH:6][C:5]([S:8]([NH:11][C@@H:12]([C:16]([OH:18])=[O:17])[CH:13]([CH3:15])[CH3:14])(=[O:10])=[O:9])=[CH:4][CH:3]=1.[CH3:19][C:20](=[CH2:22])[CH3:21].OS(O)(=O)=O>C(Cl)Cl.O1CCOCC1>[F:1][C:2]1[CH:3]=[CH:4][C:5]([S:8]([NH:11][C@@H:12]([C:16]([O:18][C:20]([CH3:22])([CH3:21])[CH3:19])=[O:17])[CH:13]([CH3:15])[CH3:14])(=[O:9])=[O:10])=[CH:6][CH:7]=1

Participants

Procedure

A solution of N-[(4-fluorophenyl)-sulfonyl]-D-valine from Example 1a (8.00 g, 29.1 mmol) in CH2Cl2 /dioxane was treated with isobutylene in the presence of H2SO4 at room temperature at a pressure of 18 psi. The reaction was quenched by adding the solution to a mixture of NaHCO3 (20 g) in water (300 mL) cooled in an ice bath. The mixture was extracted with ethyl acetate. The ethyl acetate layers were combined and washed with H2O and brine, dried over MgSO4, and concentrated to a solid. Recrystallization from diethyl ether/hexane afforded N-[(4-fluorophenyl)-sulfonyl]-D-valine, 1,1-dimethylethyl ester, as a white solid (6.99 g, 73%): MS MH+ calc'd for Cl5H22NO4SF: 332, found: 332. Anal. calc'd for Cl5H22NO4SF: C, 54.36; H, 6.69; N, 4.23. Found: C, 54.21; H, 6.86; N, 4.14.