Reaktion #64387

Reaktionsgleichung

HCl

n-BuLi

4-ethylphenyl-t-butylsulfonamide

B(OiPr)3

→

titled compound

2-t-butylsulfonamido-5-ethylphenylboric acid

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONTo the mixture, containing the bright orange dianion at 0° C.
2. 2
   Temperaturto warm to rt
3. 3
   workup.STIRRINGstirred overnight
4. 4
   workup.STIRRINGthe mixture was stirred for 1 h
5. 5
   SonstigeThe solvent was removed under reduced pressure
6. 6
   Extraktionthe residue was extracted with EtOAc
7. 7
   WaschenThe organic was washed with 2N HCl, H2O and brine
8. 8
   TrocknenThe organic was dried over anhydrous MgSO4
9. 9
   Einengenconcentrated in vacuo

Vorschrift

To a solution of 4-ethylphenyl-t-butylsulfonamide (6.44 g, 26.7 mmoL) in anhydrous THF (60 mL) cooled to -20° C. under N2 was added 2.5M n-BuLi solution (27 mL, 2.5 equiv). The mixture was warmed to rt and stirred for 2 h. To the mixture, containing the bright orange dianion at 0° C., was added B(OiPr)3 (9.3 mL, 1.5 equiv). The reaction was allowed to warm to rt and stirred overnight. The next day 2N HCl (3 mL) was added and the mixture was stirred for 1 h. The solvent was removed under reduced pressure and the residue was extracted with EtOAc. The organic was washed with 2N HCl, H2O and brine. The organic was dried over anhydrous MgSO4 and concentrated in vacuo to afford the titled compound. Rf=0.5 (1:1 EtOAc/Hex). The material was used in subsequent steps without further purification.

Quelle