Reaktion #60397

Reaktionsgleichung

sodium potassium tartrate

HOAc

(7-cyano-chroman-4-yl)-methyl-carbamic acid tert-butyl ester

diisobutylaluminum hydride

→

title compound

(7-formyl-chroman-4-yl)-methyl-carbamic acid tert-butyl ester

Lösungsmittel

H2O

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction was warmed to RT spontaneously
2. 2
   workup.STIRRINGstirred at this temperature for an additional 1.5 h
3. 3
   Extraktionthe mixture was extracted with EtOAc (60 mL)
4. 4
   Extraktionextracted with EtOAc (60 mL×2)
5. 5
   WaschenCombined organic phase was washed with saturated NaCl
6. 6
   Trocknendried over Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated

Vorschrift

To a solution of (7-cyano-chroman-4-yl)-methyl-carbamic acid tert-butyl ester (299 mg, 1.04 mmol, 1.0 eq) in anhydrous toluene (5 mL) under N2 at −20° C. was added diisobutylaluminum hydride (Aldrich, 1.50 M in toluene, 1.38 mL, 2.08 mmol, 2.0 eq) slowly. The reaction was stirred at −20° C. for 1 h. Glacial HOAc (1 mL) and H2O (5 mL) was added sequentially. The reaction was warmed to RT spontaneously and stirred at this temperature for an additional 1.5 h. A solution of saturated sodium potassium tartrate (50 mL) was added and the mixture was extracted with EtOAc (60 mL). The aqueous layer was adjusted to pH-10 with 2N NaOH, and extracted with EtOAc (60 mL×2). Combined organic phase was washed with saturated NaCl, dried over Na2SO4, filtered and concentrated. Flash column chromatography (silica gel, 0-8% EtOAc-Hexane) afforded the title compound as a colorless sticky solid.

Quelle