Реакция #2146746

Уравнение реакции

(3R,4R,5R)-5-(2,4-dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-tetrahydrofuran-3-acetate

NaOMe

→

(3R,4S,5R)-5-(2,4-Dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-tetrahydrofuran-3-ol

Растворители

MeOH

MeOH

Условия реакции

Обработка

1. 1
   КонцентрированиеThe reaction mixture is concentrated
2. 2
   workup.DISSOLUTIONdissolved in IPAC (100 ml)
3. 3
   Промывкаwashed with 1 N HCl solution (50 mL) and water (50 mL)
4. 4
   Концентрированиеconcentrated

Методика

To (3R,4R,5R)-5-(2,4-dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-tetrahydrofuran-3-acetate (10 g, 19.1 mmol) in MeOH (150 ml) is added a solution of 30% NaOMe in MeOH (5.37 ml, 28.6 mmol) and the reaction is stirred at 20° C. for 30 mins. The reaction mixture is concentrated and dissolved in IPAC (100 ml), washed with 1 N HCl solution (50 mL) and water (50 mL) and concentrated to give (3R,4S,5R)-5-(2,4-Dichlorobenzyloxymethyl)-4-(2,4-dichlorobenzyloxy)-2-methoxy-tetrahydrofuran-3-ol as a yellowish oil. The obtained crude compound is used for the next step without further purification. 1H-NMR (CDCl3, 400 MHz): δ 7.43 (d, J=8.1 Hz, 1H), 7.35-7.31 (m, 3H), 7.23 (dd, J=2.1, 4.0 Hz, 1H), 7.21-7.10 (dd, J=2.1, 4.0 Hz, 1H), 4.92 (d, J=4.6 Hz 1H), 4.77 (d, J=13.4 Hz, 1H), 4.68 (d, J=13.4 Hz, 1H); 4.60 (d, J=13.0 Hz, 1H), 4.56 (d, J=13.0 Hz, 1H), 4.25 (q, J=4.0 Hz, 1H), 4.19 (dd, J=6.8, 4.8 Hz, 1H) 3.86 (dd J=6.9, 7.0 Hz 1H), 3.60 (d, J=10.5 Hz, 2H), 3.48 (s, 3H); 13C-NMR (CDCl3, 100 MHz): δ 134.2, 134.1, 133.9, 133.5, 133.4, 129.9, 129.8, 129.1, 129.08, 127.11, 127.08, 102.8, 81.6, 77.4, 72.0, 70.8, 70.0, 69.5, 55.6 (one carbon overlapped); ESI-MS: calcd. for C20H20Cl4O5 (M+NH4+, 480.0). found: 498.0.

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