Reaktion #5659

Reaktionsgleichung

THF

benzyl bromide

sodium bis(trimethylsilyl)amide

benzhydryl 4-(2-furyl)-3-oxaoctanoate

Benzhydryl 4-(2-furyl)-3-oxaoctanoate

→

(2R,4S) benzhydryl 2-Benzyl-4-(2-furyl)-3-oxaoctanoate

4S

Benzhydryl 4-(2-furyl)-3-oxaoctanoate

Lösungsmittel

HMPA

Reaktionsbedingungen

Vorschrift

Using the procedure in example 90 and (4S) benzhydryl 4-(2-furyl)-3-oxaoctanoate (5.0 g, 13.2 mmol), THF (50 mL), sodium bis(trimethylsilyl)amide (1.0M in THF, 14 mL, 14 mmol), and benzyl bromide (1.7 mL, 14 mmol) in 10 mL HMPA gave (2R,4S) benzhydryl 2-Benzyl-4-(2-furyl)-3-oxaoctanoate, 646.6 mg (10%) and 723 mg (12%) of the (2S 4S) diastereomer which was identical to the sample prepared in example 90. (2R,4S) diastereomer: [α]25D -34.8° (c 1.12, CHCl3); 1H NMR (300 MHz, CDCl3) δ 0.78 (t, 3H, J=7 Hz), 1.12 (m, 4H), 1.69 (m, 1H), 1.83 (m, 1H), 2.98 (m, 2H), 4.11 (t, 1H, J=7 Hz), 4.21 (dd, 1H, J=8 Hz), 6.07 (m, 2H), 6.72 (s, 1H), 7.26 (m, 16H); mass spectrum (FAB): 486 (M+NH4).

Quelle