Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 927-68-4, name is 2-Bromoethyl acetate, A new synthetic method of this compound is introduced below., category: esters-buliding-blocks
(1) Synthesis of (+-)-1-(2-acetoxyethyl)-2-oxocyclopentanecarboxylic acid methyl ester To a dry acetone solution (500 ml) containing 31.0 g (0.218 moles) of 2-oxocyclopentanecarboxylic acid methyl ester and 40.0 g (0.240 moles) of 2-bromoethyl acetate, 45 g (0.326 moles) of potassium carbonate was added to prepare a suspension, and the prepared suspension was stirred at 60C for 24 hours. After the suspension was cooled to the room temperature by leaving standing, the suspension was filtered. The filtrate was diluted with ethyl acetate (500 ml), washed with hydrochloric acid (0.1 mole/liter), water and a saturated aqueous solution of sodium chloride, dried over sodium sulfate and concentrated under a reduced pressure. The obtained residue was purified in accordance with the silica gel column chromatography using a hexane/ethyl acetate mixed solvent (the ratio of the amounts by volume: 3/1) as the elution solvent, and 34.8 g (0.152 moles) of (+-)-1-(2-acetoxyethyl)-2-oxocyclopentanecarboxylic acid methyl ester was obtained as a colorless transparent liquid substance. The yield was 70%. The analytical data of the obtained compound are shown in the following. FTIR (CHCl3): 2958, 1735, 1435, 1232 1H-NMR (400 MHz): 4.19 (dt, J=11.2, 6.8 Hz, 1H), one of -CH2OAc, 4.08 (dt, J=11.2, 6.8 Hz, 1H), one of -CH2OAc, 3.70 (s, 3H), -CO2CH3, 2.56 (ddd, J=12.6, 6.8, 2.0 Hz, 1H), one of -CH2-C=O, 2.45 (dd, J=6.8, 4.8 Hz, 1H); 2.41 (d, J=8.4, 4.8 Hz, 1H), 2.31 (dd, J=14.4, 6.8 Hz, 1H), 2.25 (dd, J=14.4, 8.4 Hz, 1H), 2.00 (s, 3H).-OCOCH3, 2.06-1.67 (m, 3H) 13C-NMR (100 MHz): 213.8 (C) carbon of ketone C=O, 170.8 (C) carbon of ester C=O, 170.6 (C) carbon of ester C=O, 60.9 (CH2) methylene carbon adjacent to OAc, 58.5 (C) quaternary carbon, 52.7 (CH3) methyl carbon of ester of CO2Me, 37.5 (CH2), 32.8 (CH2), 32.5 (CH2), 20.9 (CH3) methyl carbon of acetate, 19.7 (CH2) HRMS (EI): Calcd. for C11H16O5 (M+) 228.0998, Found: 228.0979
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; ZEON CORPORATION; EP1719746; (2006); A1;,
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