* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.
L-Norvaline (160 g, 1.34 mol) is dissolved in a 28.5percent methanolic solution of HC1 (278 g) and diluted with methanol (500 ml). The solution is refluxed under inert atmosphere for 6 hours. When the reaction has terminated, the solvents are distilled by coevaporating with toluene. The residue is treated at 50°C with tert-butyl methyl ether (800 ml). The suspension obtained is left under stirring at room temperature and then filtered, and the white solid obtained is washed with tert-butyl methyl ether to obtain 216 g of L-norvaline methyl ester hydrochloride with a yield of 97percent.
86%
at 0 - 20℃; for 14 h;
HCL 3. 0g [(25.] 6 mmol, 1.0 Eq. ) of [L-NORVALINE] was dissolved in 50.0 mL of methanol and cooled to 0 [°C.] This was saturated with [HCI] gas and gradually allowed to warm to room temperature. After 14 hours the solvent was removed and the solid was dried overnight in a [DESSICATOR] with phosphorous [PENTACHLORIDE.] 3.6g (86percent) of a white solid was obtained. (MS: 126. [9/] [[P-APOS;])] (H'NMR in [CDCI3] : 0.95, 3H t, (J=382 Hz), 1.46, 2H m, (J=587 Hz), 2.01, 2H m, (J=806 Hz), 3 78,3H s, [(J=1512] Hz), 4.05, 1H m, [(J=1622.] 459 Hz), 8.74, 2H brds, (J=3495 Hz))
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