ChemicalBook CAS DataBase List (-)-DIMETHYL 2,3-O-BENZYLIDENE-L-TARTRATE

(-)-DIMETHYL 2,3-O-BENZYLIDENE-L-TARTRATE synthesis

3synthesis methods

Product Name:(-)-DIMETHYL 2,3-O-BENZYLIDENE-L-TARTRATE
CAS Number:38270-72-3
Molecular formula:C13H14O6
Molecular Weight:266.25

608-68-4 Synthesis

608-68-4
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$14.00/5g

100-52-7 Synthesis

100-52-7
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$20.37/250g

(-)-DIMETHYL 2,3-O-BENZYLIDENE-L-TARTRATE

38270-72-3
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Yield:38270-72-3 84%

Reaction Conditions:

with toluene-4-sulfonic acid in benzene; for 38.5 h;Reflux;Dean-Stark;Inert atmosphere;

Steps:

Dimethyl (4R,5R)-2-phenyl-1,3-dioxolane-4,5-dicarboxylate (17)

To a solution of dimethyl l-tartrate (22g, 0.15mol) in dry benzene (220mL) were successively added benzaldehyde (18.3mL, 0.18mol) and p-TsOH (0.73g, 3.84mmol), and the resulting mixture was stirred at reflux for 38.5h using a Dean-Stark device. Then, the reaction mixture was neutralized with Et₃N (0.73mL), the solvent was removed under reduced pressure, and the residue was purified by flash chromatography on silica gel (n-hexane/ethyl acetate, 5:1) to give 32.77g (84%) of compound 17 as white crystals mp 71-71.5°C (recrystallized from n-hexane/ethyl acetate); {[α]_D²⁷ -43.1 (c 0.54, MeOH); lit.³⁰ [α]_D -42.0 (c 0.50, temperature and solvent not reported); lit.³⁴ [α]_D²⁰ -47.2 (c 1.00, MeOH)}. IR (neat) ν_max 2958, 2909, 1751, 1429, 1236, 1214, 1102, 1079cm^-1; ¹H NMR (400MHz, CDCl₃): δ 3.83 (s, 3H, OCH₃), 3.87 (s, 3H, OCH₃), 4.87 (d, 1H, J=4.0Hz, CH), 4.98 (d, 1H, J=4.0Hz, CH), 6.14 (s, 1H, H-2), 7.39-7.41 (m, 3H, Ph), 7.57-7.59 (m, 2H, Ph); ¹³C NMR (100MHz, CDCl₃): δ 52.9 (2× OCH₃), 77.2 (CH), 77.4 (CH), 106.7 (C-2), 127.2 (2× CH_Ph), 128.4 (2× CH_Ph), 130.0 (CH_Ph), 135.2 (C_i), 169.4 (C=O), 170.0 (C=O). Anal. Calcd for C₁₃H₁₄O₆: C, 58.64; H, 5.30. Found: C, 58.60; H, 5.35.