Benzyl iodide → (3R,4R)-3-Benzyl-4-isopropyl-dihydro-furan-2-one
Reaction equation
C[Si]([N-][Si](C)(C)C)(C)C.[Li+].[CH3:11][CH:12]([C@H:14]1[CH2:19][O:18][C:16](=[O:17])[CH2:15]1)[CH3:13].[CH2:20](I)[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1>C1COCC1>[CH2:20]([C@@H:15]1[C@@H:14]([CH:12]([CH3:13])[CH3:11])[CH2:19][O:18][C:16]1=[O:17])[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1Participants
Procedure
Lithium bis(trimethylsilyl)amide (1.0 M solution in THF, 92 mL, 92 mmol) was added in 3 to 5 minutes to a solution of (S)-β-(2-propyl)-γ-butyrolactone 175 (11.68 g, 91.25 mmol) in dry THF 100 mL at −78° C. under argon atmosphere. It was stirred for 1 hour and a solution of benzyl iodide (21.87 g, 100.37 mmol) in dry THF was added rapidly. Stirring was continued for 1.5 hours and quenched at −78° C. by the addition of a solution of brine followed by ethyl acetate. The organic phase was separated and the aqueous was further extracted with ether. Chromatography on silica gel first eluted with 5% methylene chloride in pet ether, and finally with 10% ether in pet ether gave desired compound 11.6 g, 58%. NMR (CDCl3) δ 7.19 (m, 5H, C6H5), 4.02 (app. t, 1H, CHaHbO), 3.87 (dd, 1H, CHaHbO), 2.98 (d, 2H, ArCH2), 2.57 (q, 1H, BnCHC═O), 2.05 (m, 1H, CHCH(Me)2, 1.55 (m, 1H, CH(Me)2), 0.81 (d, 3H, CH3) and 0.72 (d, 3H, CH3).
Workup
- stirringStirring
- waitwas continued for 1.5 hours
- customquenched at −78° C. by the addition of a solution of brine
- customThe organic phase was separated
- extractionthe aqueous was further extracted with ether
- washChromatography on silica gel first eluted with 5% methylene chloride in pet ether
Sources & evidence
- ORD record
- ord-1683a1ff48014320ba57e6f2c308da1e
- Source dataset
- uspto-grants-2003_09
- Patent number
- US06620829B2
Reaction notes
Loading…