3,4-dihydro-2H-pyran → 6-(Tetrahydropyran-2-yloxymethyl)-4H-benzo[1,4]oxazin-3-one
Reaction equation
[OH:1][CH2:2][C:3]1[CH:4]=[CH:5][C:6]2[O:11][CH2:10][C:9](=[O:12])[NH:8][C:7]=2[CH:13]=1.[O:14]1[CH:19]=[CH:18][CH2:17][CH2:16][CH2:15]1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1.C(=O)([O-])O.[Na+]>ClCCl>[O:14]1[CH2:19][CH2:18][CH2:17][CH2:16][CH:15]1[O:1][CH2:2][C:3]1[CH:4]=[CH:5][C:6]2[O:11][CH2:10][C:9](=[O:12])[NH:8][C:7]=2[CH:13]=1Participants
6
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
The solution of 5.0 g of 6-hydroxymethyl-4H-benzo[1,4]oxazin-3-one in 60 ml of dichloromethane is admixed successively with 5.20 ml of 3,4-dihydro-2H-pyran and 0.236 g of p-toluenesulphonic acid monohydrate. The reaction mixture is stirred at room temperature over 14 hours. The solution is poured onto 1M sodium hydrogencarbonate solution (300 ml) and extracted with tert-butyl methyl ether (2×400 ml). The organic phase is washed with brine (300 ml), dried over sodium sulphate, filtered and concentrated by evaporation. The title compound is obtained as a beige solid from the residue by means of crystallization (EtOAc/heptane). Rf=025 (1:1 EtOAc-heptane); Rt=3.45.
Workup
- extractionextracted with tert-butyl methyl ether (2×400 ml)
- washThe organic phase is washed with brine (300 ml)
- dry with materialdried over sodium sulphate
- filtrationfiltered
- concentrationconcentrated by evaporation
Sources & evidence
- ORD record
- ord-fa690dcb2a6940ef8ae9143ea7ff01b5
- Source dataset
- uspto-grants-2010_09
- Patent number
- US07790715B2
Reaction notes
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