(Diethylamino)sulfur trifluoride → 4-[(Dimethoxy-phosphoryl)fluoro-methyl]-benzoic acid benzyl ester
Reaction equation
[CH2:1]([O:8][C:9](=[O:24])[C:10]1[CH:15]=[CH:14][C:13]([CH:16]([P:18]([O:22][CH3:23])([O:20][CH3:21])=[O:19])O)=[CH:12][CH:11]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.CCN(S(F)(F)[F:31])CC>>[CH2:1]([O:8][C:9](=[O:24])[C:10]1[CH:15]=[CH:14][C:13]([CH:16]([P:18]([O:22][CH3:23])([O:20][CH3:21])=[O:19])[F:31])=[CH:12][CH:11]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Participants
3
Conditions
- Temperature
- -78 °C
Procedure
4-[(Dimethoxy-phosphoryl)-hydroxy-methyl]-benzoic acid benzyl ester (0.20 g, 0.22 mmol) was added over 30 mins to a stirring solution of DAST (1M in CH2Cl2) cooled to −78° C. under a dry nitrogen environment. The mixture was warmed to RT and stirred for 18 hours. The reaction mixture was then quenched with ethanol containing pyridine (pyr: twice volume of DAST). After another 30 mins the mixture was poured into ice cold water and extracted into DCM (3×). The combined organic extracts were washed with dilute aq HCl, water, brine, dried (MgSO4) then concentrated in vacuo. The residue was purified by HPLC (20-85% MeCN in Water w/0.025% TFA) to afford the title compound: MS: cal'd 353 (MH+), exp 353 (MH+)