Triacetoxyperiodinane → t-butyl (1R)-1-(4-(2-methylpentyloxy)phenyl)-2-oxoethylcarbamate
Reaction equation
[OH:1][CH2:2][C@H:3]([NH:17][C:18](=[O:24])[O:19][C:20]([CH3:23])([CH3:22])[CH3:21])[C:4]1[CH:9]=[CH:8][C:7]([O:10][CH2:11][CH:12]([CH3:16])[CH2:13][CH2:14][CH3:15])=[CH:6][CH:5]=1.C(=O)(O)[O-].[Na+].CC(OI1(OC(C)=O)(OC(C)=O)OC(=O)C2C=CC=CC1=2)=O.OS([O-])=O.[Na+]>ClCCl>[CH3:16][CH:12]([CH2:13][CH2:14][CH3:15])[CH2:11][O:10][C:7]1[CH:6]=[CH:5][C:4]([C@@H:3]([NH:17][C:18](=[O:24])[O:19][C:20]([CH3:22])([CH3:21])[CH3:23])[CH:2]=[O:1])=[CH:9][CH:8]=1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
A solution of t-butyl (1R)-2-hydroxy-1-(4-(2-methylpentyloxy)phenyl)ethylcarbamate (500 mg, 1.48 mmol) prepared according to the procedure described in example 1, in dichloromethane (10 mL) was treated with sodium bicarbonate (622 mg, 7.41 mmol) and Dess-Martin Periodinane (1.26 g, 2.96 mmol) at room temperature. The mixture was stirred at room temperature under N2 for 1.5 h. The reaction mixture was placed in an ice-water bath and a 1:1 mixture of saturated aqueous NaHCO3 solution and saturated NaHSO3 solution (4 mL) was added and the cooling bath was removed and the mixture was stirred for 5 min at room temperature. The reaction mixture was transferred to a separatory funnel containing saturated aqueous NaHCO3 solution (20 mL). The aqueous layer was extracted with ethyl acetate (3×25 mL). The combined organic layers were washed with brine (20 mL), dried over MgSO4, filtered and concentrated. The residue was purified by column chromatography on silica gel (10%→15% ethyl acetate in hexanes, 25 g column) to afford t-butyl (1R)-1-(4-(2-methylpentyloxy)phenyl)-2-oxoethylcarbamate (318 mg, 64% yield) as a colorless oil which was stored in the freezer until used in the next step: 1H NMR (400 MHz, DMSO-d6) δ 9.48 (s, 1H), 7.76 (d, J=7.6 Hz, 1H), 7.23 (d, J=8.6 Hz, 2H), 6.93 (d, J=8.6 Hz, 2H), 5.11 (d, J=7.6 Hz, 1H), 3.82 (dd, J=9.6, 6.0 Hz, 1H), 3.73 (dd, J=9.3, 6.5 Hz, 1H), 1.82-1.92 (m, 1H), 1.40 (s, 9H), 1.25-1.49 (m, 3H), 1.11-1.22 (m, 1H), 0.96 (d, J=6.8 Hz, 3H), 0.88 (t, J=7.1 Hz, 3H); LRMS (ESI) m/e 279.2 [(M-t-Bu)+, calcd for C15H21NO4 279.1].
Workup
- customThe reaction mixture was placed in an ice-water bath
- additionwas added
- customthe cooling bath was removed
- stirringthe mixture was stirred for 5 min at room temperature
- customThe reaction mixture was transferred to a separatory funnel
- additioncontaining saturated aqueous NaHCO3 solution (20 mL)
- extractionThe aqueous layer was extracted with ethyl acetate (3×25 mL)
- washThe combined organic layers were washed with brine (20 mL)
- dry with materialdried over MgSO4
- filtrationfiltered
- concentrationconcentrated
- customThe residue was purified by column chromatography on silica gel (10%→15% ethyl acetate in hexanes, 25 g column)
Sources & evidence
- ORD record
- ord-44cc3ddc1c6a415d9fbbd4b496ef63e4
- Source dataset
- uspto-grants-2012_11
- Patent number
- US08304577B2
Reaction notes
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