Reaktion #50177

Reaktionsgleichung

hydrogen

sodium hydride

methyl iodide

4-hydroxy-4-[3-(tetrahydropyran-2-yloxy)-prop-1-ynyl]tetrahydropyran

→

4-methoxy-4-[3-(tetrahydropyran-2-yloxy)prop-1-ynyl]tetrahydropyran

Ausbeute 96.1%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   SonstigeThe reaction was quenched by addition of crushed ice and saturated aqueous NH4Cl
3. 3
   ExtraktionThe resulting two-phase mixture was extracted with ether (3×100 mL)
4. 4
   TrocknenThe combined organic layers were dried over MgSO4
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated in vacuo
7. 7
   SonstigePurification by chromatography on silica gel (100 g, 10% ethyl acetate: hexanes)

Vorschrift

To a suspension of sodium hydride (1.2 g of an 80% oil dispersion, 50 mmol) in dry THF (45 mL) was added a solution of 4-hydroxy-4-[3-(tetrahydropyran-2-yloxy)-prop-1-ynyl]tetrahydropyran(3.71 g, 15.3 mmol), prepared as in step 1. After hydrogen evolution ceased, methyl iodide (3.0 mL, 48.2 mmol) was added neat and the resulting solution was stirred overnight at ambient temperature. The reaction was quenched by addition of crushed ice and saturated aqueous NH4Cl. The resulting two-phase mixture was extracted with ether (3×100 mL). The combined organic layers were dried over MgSO4, filtered, and concentrated in vacuo. Purification by chromatography on silica gel (100 g, 10% ethyl acetate: hexanes) provided 4-methoxy-4-[3-(tetrahydropyran-2-yloxy)prop-1-ynyl]tetrahydropyran (3.74 g, 95 %) as a colorless oil.

Quelle