Sodium Carbonate → (1R,5R)-2,2,2-trichloroethyl-5-hydroxy-2-cyclopentene-1-carbamate
Reaction equation
[NH2:1][C@H:2]1[C@H:6]([OH:7])[CH2:5][CH:4]=[CH:3]1.C(=O)([O-])[O-].[Na+].[Na+].[Cl:14][C:15]([Cl:22])([Cl:21])[CH2:16][O:17][C:18](Cl)=[O:19]>O>[Cl:14][C:15]([Cl:22])([Cl:21])[CH2:16][O:17][C:18](=[O:19])[NH:1][C@H:2]1[C@H:6]([OH:7])[CH2:5][CH:4]=[CH:3]1Participants
Procedure
A 10.18 (103 mM) quantity of crude (3R, 4R)-3-amino-4-hydroxycyclopentene (prepared as in Preparation 19, step 4) is dissolved in 75 ml of water and the mixture treated with 10.6 g (100 mM) of sodium carbonate. The mixture is then cooled in an ice bath to <10° and treated dropwise while stirring vigorously, with 24 g (110 mM) of trichloroethylchloroformate over 30 minutes. After 3 hours the reaction is filtered and the collected solid product washed throughly with water. On drying there is obtained 22.43 g of (1R, 5R)-2,2,2-trichloroethyl-5-hydroxy-2-cyclopentene-1-carbamate as crystalline solid, m.p. 82°-84°. Recrystallization of a small sample from isopropylether-Skellysolve B gives material with a m.p. 87°-87.5° [α]-92° (C=0.14, MeOH).
Workup
- temperatureThe mixture is then cooled in an ice bath to <10°
- additiontreated dropwise
- filtrationAfter 3 hours the reaction is filtered
- washthe collected solid product washed throughly with water
- customOn drying there
Sources & evidence
- ORD record
- ord-b7321b3819f841e2956489053941d03b
- Source dataset
- uspto-grants-1981_11
- Patent number
- US04298744
Reaction notes
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