تفاعل #80548

معادلة التفاعل

(R)-8-Fluoro-3-(N,N-dicyclobutylamino)-5-methoxy-3,4-dihydro-2H-1-benzopyran hydrochloride

BBr3

→

title compound

المردود 89.0%

(R)-8-Fluoro-3-(N,N-dicyclobutylamino)-5-hydroxy-3,4-dihydro-2H-1-benzopyran

المردود 89.0%

المذيبات

CH2Cl2

CH2Cl2

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONadded dropwise
2. 2
   أخرىThe cooling-bath was removed and after 2 h at room temperature the reaction
3. 3
   workup.ADDITIONThe reaction was poured out onto an ice/2M NH3 solution
4. 4
   استخلاصthe mixture was extracted
5. 5
   ترشيحtwice, with (MgSO4), filtered
6. 6
   أخرىthe solvent removed in vacuo to diethyl ether
7. 7
   تجفيفThe combined ether portions were dried
8. 8
   أخرىgive the crude residue

الإجراء التجريبي

(R)-8-Fluoro-3-(N,N-dicyclobutylamino)-5-methoxy-3,4-dihydro-2H-1-benzopyran hydrochloride (0.77 g, 2.26 mmol) was dissolved in anhydrous CH2Cl2 (20 mL) and cooled to -40° C. To the solution was BBr3 (0.54 mL, 5.7 mmol), dissolved in anhydrous CH2Cl2 (3 mL), added dropwise. The cooling-bath was removed and after 2 h at room temperature the reaction was completed. The reaction was poured out onto an ice/2M NH3 solution and the mixture was extracted, twice, with (MgSO4), filtered, and the solvent removed in vacuo to diethyl ether. The combined ether portions were dried give the crude residue. Chromatography on silica (eluent: 50% ethyl acetate/hexane) gave 0.58 g (89% yield) of the title compound as a white solid. Mp: 170°-2° C. [α]21D =-114.4° (C=0.1; CHCl3) GC-MS (70 eV) M=291 (2%).

المصدر