تفاعل #984070

معادلة التفاعل

N-benzyl[(2R)-3,4-dihydro-2H-chromen-2-yl]methanamine hydrobromide

bromine

water

→

N-benzyl-N-{[(2R)-6-bromo-3,4-dihydro-2H-chromen-2-yl]methyl}amine

المردود 84.3%

المذيبات

formic acid

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةmaintaining the reaction temperature between 15 and 16° C
2. 2
   أخرىthe reaction
3. 3
   أخرىThe light reaction mixture
4. 4
   ترشيحthe product was filtered
5. 5
   غسيلwashed with 3.9 L water
6. 6
   workup.ADDITIONTo this suspension was added 13 L 1M NaHCO3
7. 7
   أخرىThe aqueous phase was separated (14.5 L; pH=8)
8. 8
   غسيلthe organic phase was washed with 6.5 L water
9. 9
   أخرىThe phases were separated
10. 10
    أخرىthe organic phase evaporated at 45° C.

الإجراء التجريبي

In a 30 L reaction vessel, N-benzyl[(2R)-3,4-dihydro-2H-chromen-2-yl]methanamine hydrobromide (2173 g, 6.5 moles, 1.0 eq.) was suspended in 11.4 L formic acid. The suspension was cooled to 16° C., then bromine (1071 g, 6.7 moles, 1.03 eq.) was added over a 60 minutes, maintaining the reaction temperature between 15 and 16° C. After 70 minutes, a HPLC probe indicated the reaction to be complete. To the reaction mixture was then added 15.6 L water (temperature increased to 21° C.). The light reaction mixture was then stirred for 30 minutes at room temperature, then the product was filtered and washed with 3.9 L water. The 3.14 kg of light gray moist product was then suspended in 9.75 L dichloromethane. To this suspension was added 13 L 1M NaHCO3. Foaming ensued and the suspension became a bi-phasic solution. The aqueous phase was separated (14.5 L; pH=8) and the organic phase was washed with 6.5 L water. The phases were separated and the organic phase evaporated at 45° C. to yield 1820 g of N-benzyl-N-{[(2R)-6-bromo-3,4-dihydro-2H-chromen-2-yl]methyl}amine.

المصدر