Ethyl cycloheptanecarboxylate → Ethyl 1-(2,3-dimethoxybenzyl)cycloheptane Carboxylate
Reaction equation
[CH:1]1([C:8]([O:10][CH2:11][CH3:12])=[O:9])[CH2:7][CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.[Li+].CC([N-]C(C)C)C.[CH3:21][O:22][C:23]1[C:30]([O:31][CH3:32])=[CH:29][CH:28]=[CH:27][C:24]=1[CH2:25]Br>C(O)C.C1COCC1>[CH3:21][O:22][C:23]1[C:30]([O:31][CH3:32])=[CH:29][CH:28]=[CH:27][C:24]=1[CH2:25][C:1]1([C:8]([O:10][CH2:11][CH3:12])=[O:9])[CH2:7][CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1Participants
Conditions
- Temperature
- -78 °C
Procedure
To a stirred solution of ethyl cycloheptane carboxylate (14 g, 82.4 mmol, prepared by esterification of the acid, which was obtained from Aldrich, by refluxing in ethanol in the presence of an acid catalyst), in 600 mL anhydrous THF cooled to -78° C. was added 60 mL of 1.5M LDA (monotetrahydrofuran in hexane, Aldrich) via syringe. The resulting light yellow reaction solution was stirred at -78° C. for 45 min and the benzyl bromide (from step A above) was added (19 g dissolved in 75 mL of THF, 82.4 mmol). The reaction was stirred at -78° C. for 4 hours, then it was quenched by addition of sat'd. NH4Cl, water and ether. The layers were separated, and the organic layer was washed with 1M HCl, water, and brine. The organic layer was dried over MgSO4, filtered, and evaporated to yield a light amber oil (28 g) which was used without further purification.
Workup
- stirringThe reaction was stirred at -78° C. for 4 hours
- customit was quenched by addition of sat'd
- customThe layers were separated
- washthe organic layer was washed with 1M HCl, water, and brine
- dry with materialThe organic layer was dried over MgSO4
- filtrationfiltered
- customevaporated
Sources & evidence
- ORD record
- ord-bd9c79c4509d4fddafe0594b59924ecb
- Source dataset
- uspto-grants-1997_04
- Patent number
- US05621133
Reaction notes
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