反応 #7771

反応方程式

NH4Cl

BF3 Et2O

(±)(1S*,2R*,4S*)-4-(benzyloxy)-1,2-epoxycyclohexane

1-Methanesulfonyl-4-methylsulfanyl-benzene

nBuLi

→

(±)(1R*,2R*,5S*)-5-benzyloxy-2-(4-methylsulfanyl-benzenesulfonylmethyl)-cyclohexanol

収率 80.3%

溶媒

THF

EtOAc

THF

反応条件

後処理

1. 1
   workup.ADDITIONAfter an addition 1 h at −78° C.
2. 2
   温度the solution was warmed to 0° C
3. 3
   workup.WAITAfter 2 h
4. 4
   温度the solution was cooled to −78° C.
5. 5
   温度The solution was warmed to rt
6. 6
   洗浄The organic layer was washed with brine
7. 7
   その他dried
8. 8
   ろ過filtered
9. 9
   濃縮concentrated

実験手順

1-Methanesulfonyl-4-methylsulfanyl-benzene (3.25 g) was dissolved in THF (50 mL) and cooled to −78° C. prior to the addition of 1.6 M nBuLi (10 mL). After 0.5 h, BF3-Et2O (2.04 mL) was added followed by (±)(1S*,2R*,4S*)-4-(benzyloxy)-1,2-epoxycyclohexane (2.19 g) (Chini et al. J. Org. Chem. 1990, 55, 4265) in THF (20 mL). After an addition 1 h at −78° C., the solution was warmed to 0° C. After 2 h, the solution was cooled to −78° C. and saturated NH4Cl solution (aq) was added. The solution was warmed to rt and EtOAc was added. The organic layer was washed with brine, dried, filtered, and concentrated. Flash chromatography of the resulting residue gave (±)(1R*,2R*,5S*)-5-benzyloxy-2-(4-methylsulfanyl-benzenesulfonylmethyl)-cyclohexanol (3.5 g) as the major product: 1H NMR (CDCl3, δ ppm, 300 mHz) 1.41 (m, 2H), 1.59 (m, 1H), 1.95 (m, 1H), 2.05-2.35 (m, 2H), 2.54 (s, 3H), 2.96 (dd, 1H), 3.64 (m, 2H), 3.81 (s, 1H), 4.48 (m, 2H), 7.3 (m, 7H), 7.82 (d, 2H)

出典