تفاعل #80553

معادلة التفاعل

acetic acid

sodium cyanoborohydride

(R)-3-Amino-8-fluoro-5-methoxy-3,4-dihydro-2H-1-benzopyran

acetone

→

crude residue

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

المذيبات

methanol

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONadded
2. 2
   درجة الحرارةThe reaction was cooled (ice-bath)
3. 3
   أخرىThe solvent was removed in vacuo
4. 4
   استخلاصextracted thrice with diethyl ether
5. 5
   تجفيفThe combined ether portions were dried (MgSO4)
6. 6
   ترشيحfiltered
7. 7
   أخرىthe solvent removed in vacuo

الإجراء التجريبي

(R)-3-Amino-8-fluoro-5-methoxy-3,4-dihydro-2H-1-benzopyran (1.62 g, 8.21 mmol) was dissolved in anhydrous methanol (20 mL) and to this was acetone (6.0 mL, 82.1 mmol) added. The reaction was cooled (ice-bath) then sodium cyanoborohydride (0.92 g, 14.8 mmol) was added, the pH was adjusted to 4-5 with acetic acid and the reaction was allowed to stir at room temperature overnight. The solvent was removed in vacuo, the remains were taken into a 2M solution of NH3 and then extracted thrice with diethyl ether. The combined ether portions were dried (MgSO4), filtered, and the solvent removed in vacuo to give the crude residue that was used as is in the next reaction. GC-MS (70 eV) M=239 (81%).

المصدر