Methyl acetoacetate → HCID 57219343, compound

HRID 1107121Notes

Reaction equation

[H-].[Na+].[C:3]([O:9][CH3:10])(=[O:8])[CH2:4][C:5]([CH3:7])=[O:6].C([Li])CCC.Br[CH2:17][CH2:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1>CN(C=O)C>[O:6]=[C:5]([CH:7]=[CH:17][CH2:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)[CH2:4][C:3]([O:9][CH3:10])=[O:8]

Participants

Conditions

Temperature: -25 °C

Procedure

To a suspension of 60% NaH (2.76 g, 69 mmol) in anhydrous DMF (50 mL) at 0° C. is added a solution of methyl acetoacetate (8 g) in DMF (50 mL) dropwise over 10 minutes. The mixture is cooled to -25° C. and 2.5M n-butyllithium (27.6 mL, 69 mmol) is added dropwise over 5 minutes. The mixture is stirred for 5 minutes and 1-bromo-3-phenylpropane (10.48 mL, 69 mmol) is added dropwise over 5 minutes. The cooling bath is removed and the mixture is stirred at room temperature for 2 hours. The mixture is poured into water and is extracted with ether. The organic layer is washed with water and is dried over MgSO4. The solvent is removed in vacuo and the residue is chromatographed on silica gel (6:1 hexane:ethyl acetate) to produce methyl 3-keto-7-phenylheptenoate as an oil (8 g, 50% ): 1H-NMR (300 MHz, CDCl3) δ (TMS) 1.50-1.68 (m, 4H), 2.42-2.62 (m, 4H), 3.40 (s, 2H), 3.70 (s, 3H), 7.10-7.18 (m, 2H), 7.18-7.30 (m, 3H).

Workup

customThe cooling bath is removed
stirringthe mixture is stirred at room temperature for 2 hours
additionThe mixture is poured into water
extractionis extracted with ether
washThe organic layer is washed with water
dry with materialis dried over MgSO4
customThe solvent is removed in vacuo
customthe residue is chromatographed on silica gel (6:1 hexane:ethyl acetate)

Sources & evidence

ORD record: ord-720c5b1fcf474702bc080f05f06b7e9e
Source dataset: uspto-grants-2000_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06057369

Reaction notes

Loading…