Reaktion #48632

Reaktionsgleichung

isobutylmagnesium bromide

(2S)-(+)-glycidyl tosylate

→

desired compound

Ausbeute 75.5%

Toluene-4-sulfonic acid 2-(S)-hydroxy-5-methylhexyl ester

Ausbeute 75.5%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigecannulate into the stirring Grignard reaction flask
2. 2
   SonstigeQuench with saturated aqueous ammonium chloride (25 mL)
3. 3
   workup.ADDITIONpour supernate into saturated aqueous ammonium chloride (25 mL) and water
4. 4
   WaschenWash with saturated aqueous sodium chloride
5. 5
   Trocknendry (magnesium sulfate)
6. 6
   Filtrationfilter
7. 7
   Einengenconcentrate
8. 8
   Sonstigepurify
9. 9
   Waschen(silica gel chromatography, eluting with 10:90 to 25:75 ethyl acetate:hexanes)

Vorschrift

Add dropwise over 5 minutes isobutylmagnesium bromide (4.4 mL, 8.8 mmol, 2 M in diethyl ether) to a solution of lithium tetrachlorocuprate (4.4 mL, 0.44 mmol, 0.1 M in tetrahydrofuran) cooled to −35-40° C. Dissolve (2S)-(+)-glycidyl tosylate (1.674 g, 7.73 mmol) in tetrahydrofuran (8 mL), cool to −40° C. and cannulate into the stirring Grignard reaction flask. Quench with saturated aqueous ammonium chloride (25 mL), pour supernate into saturated aqueous ammonium chloride (25 mL) and water and shake well. Wash with saturated aqueous sodium chloride, dry (magnesium sulfate), filter, concentrate and purify (silica gel chromatography, eluting with 10:90 to 25:75 ethyl acetate:hexanes) to give the desired compound (1.6711 g, 75%).

Quelle