Ethyl Propionate → 3-(3,5-Dimethoxyphenyl)-2-methylpropionic acid ethylester

HRID 1447540Notes

Reaction equation

[CH2:1]([O:3][C:4](=[O:7])[CH2:5][CH3:6])[CH3:2].[Li].[CH:9]([N-]C(C)C)(C)C.C([Li])CCC.[CH3:21][O:22][C:23]1([CH:30]=[CH:29][CH:28]=[C:27]([O:31][CH3:32])[CH2:26]1)CBr>O1CCCC1.CCCCCC.CN(C)P(=O)(N(C)C)N(C)C.O>[CH2:1]([O:3][C:4](=[O:7])[CH:5]([CH3:9])[CH2:6][C:29]1[CH:28]=[C:27]([O:31][CH3:32])[CH:26]=[C:23]([O:22][CH3:21])[CH:30]=1)[CH3:2]

Participants

Conditions

Temperature: -70 °C

Procedure

Ethylpropionate (10.2 g; 0.1 mol) was added dropwise to a solution of lithium-di-isopropylamide (0.1 mol) which was obtained by mixing at 0° C. under nitrogen 10 g di-isopropylamine in 100 ml dry tetrahydrofuran with n-butyllithium in hexane (45.5 ml; 2.2 M). After the addition of ethylpropionate (which was carried out at a temperature of -78° C.) the mixture was stirred at -78° C. for 10 minutes, whereafter a solution of 1,3-dimethoxybenzylbromide (23.0 g; 0.1 mol) in dry hexamethylphosphoric acid triamide (9 g) was added dropwise. The mixture was stirred at -70° C. for 10 minutes and then heated to 0° C. Water was added and the mixture was extracted with ether. The ether-extract was dried on Na2SO4 and the solvent was evaporated. Destillation of the residue in vacuum gave 19.4 g pure product (77% yield), boiling point 150°-155° C./0.2 mm.

Workup

customwas obtained
customwas carried out at a temperature of -78° C.
additionwas added dropwise
temperatureheated to 0° C
extractionthe mixture was extracted with ether
extractionThe ether-extract
customwas dried on Na2SO4
customthe solvent was evaporated

Sources & evidence

ORD record: ord-2dbca37536034b5fa4e9ac382990c979
Source dataset: uspto-grants-1979_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04177197

Reaction notes

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