Ethylene Glycol → 2-(2-Benzyloxy-ethyl)-[1,3-dioxolan-2-ylmethyl]-4-(4-chloro-benzene-sulfonyl)-5,8-difluoro-chroman
Reaction equation
C(OCCC(=O)C[CH:13]1[CH:22]([S:23]([C:26]2[CH:31]=[CH:30][C:29]([Cl:32])=[CH:28][CH:27]=2)(=[O:25])=[O:24])[C:21]2[C:16](=[C:17]([F:34])[CH:18]=[CH:19][C:20]=2[F:33])[O:15][CH2:14]1)C1C=CC=CC=1.[CH2:36](O)[CH2:37][OH:38].[C:40]1([CH3:50])[C:41](S(O)(=O)=O)=[CH:42][CH:43]=[CH:44][CH:45]=1.O.[C:52]([O:55][CH2:56][CH3:57])(=[O:54])[CH3:53]>C1(C)C=CC=CC=1>[CH2:50]([O:38][CH2:37][CH2:36][C:14]1([CH2:53][CH:52]2[O:54][CH2:57][CH2:56][O:55]2)[CH2:13][CH:22]([S:23]([C:26]2[CH:27]=[CH:28][C:29]([Cl:32])=[CH:30][CH:31]=2)(=[O:25])=[O:24])[C:21]2[C:16](=[C:17]([F:34])[CH:18]=[CH:19][C:20]=2[F:33])[O:15]1)[C:40]1[CH:41]=[CH:42][CH:43]=[CH:44][CH:45]=1Participants
Reactant 5
Product 1
Reagents, catalysts & solvents 1
Procedure
4-Benzyloxy-1-[4-(4-chloro-benzenesulfonyl)-5,8-difluoro-chroman-3-yl]-butan-2-one (10 g, 19.2 mmole), ethylene glycol (20 ml) and toluene sulfonic acid (1 g) were dissolved in 300 ml toluene. The reaction was refluxed for four hours with a Dean-Stark trap. The reaction was cooled to room temperature and 200 ml water and 200 ml EtOAc were added. The organic layer was washed with brine (2×50 ml), dried over Na2SO4 and concentrated. The residue was purified by column chromatography (EtOAc/hexane from 0/100 to 50/50 in 55 minute). Yield: 6.3 g, 58%. 1H NMR (CDCl3 400 MHz δ 7.74 (d, J=8.1 Hz, 2H), 7.51 (d, J=8.8 Hz, 2H), 7.20-7.39 (m, 5H), 7.02 (m, 1H), 6.42 (m, 1H), 4.89 (dd, J=11.0 and 2.9 Hz, 1H), 4.84 (s, 1H), 4.40 (d, J=2.0 Hz, 2H), 4.21 (d, J=11.7 Hz, 1H), 3.85 (m, 4H), 3.46 (t, J=5.9 Hz, 2H), 3.03 (d, J=8.1 Hz, 1H), 1.75-1.90 (m, 3H), 1.54-1.61 (m, 1H).
Workup
- temperatureThe reaction was refluxed for four hours with a Dean-Stark trap
- washThe organic layer was washed with brine (2×50 ml)
- dry with materialdried over Na2SO4
- concentrationconcentrated
- customThe residue was purified by column chromatography (EtOAc/hexane from 0/100 to 50/50 in 55 minute)
Sources & evidence
- ORD record
- ord-7587de5fac9c44f885017892497b6576
- Source dataset
- uspto-grants-2013_10
- Patent number
- US08569521B2
Reaction notes
Loading…