反応 #5659

反応方程式

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

溶媒

HMPA

反応条件

実験手順

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).

出典