Réaction #7772

Équation de réaction

(±)3,4-epoxytetrahydropyran

1-Methanesulfonyl-4-methylsulfanyl-benzene

nBuLi

NH4Cl

BF3 Et2O

→

(±)(3S*,4R*)-4-(4-methylsulfanyl-benzenesulfonylmethyl)-tetrahydro-pyran-3-ol

Rendement 35.9%

Solvants

EtOAc

THF

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONAfter an addition 1 h at −78° C.
2. 2
   Températurethe solution was warmed to 0° C
3. 3
   workup.WAITAfter 2 h
4. 4
   Températurethe solution was cooled to −78° C.
5. 5
   TempératureThe solution was warmed to rt
6. 6
   LavageThe organic layer was washed with brine
7. 7
   Autredried
8. 8
   Filtrationfiltered
9. 9
   Concentrationconcentrated

Mode opératoire

1-Methanesulfonyl-4-methylsulfanyl-benzene (4.33 g) was dissolved in THF (50 mL) and cooled to −78° C. prior to the addition of 1.6 M nBuLi (13.4 mL). After 0.5 h, BF3-Et2O (2.7 mL) was added followed (±)3,4-epoxytetrahydropyran (1.2 g) (Tetrahedron 1974, 4013). 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 (±)(3S*,4R*)-4-(4-methylsulfanyl-benzenesulfonylmethyl)-tetrahydro-pyran-3-ol (1.3 g) as the major product. MS found: (M+H)+=303.0.

Source