Reaction #55367

Reaction equation

HCl

1-methyl-4-(3-bromo-5-hydroxy-5H-dibenzo[a,d]cyclohepten-5-yl)piperidine

trifluoroacetic acid

(±)-1-methyl-4-(3-bromo-5H-dibenzo[a,d]cyclohepten-5-ylidene)piperidine hydrochloride

trifluoroacetic anhydride

→

(±)-1-methyl-4-(3-bromo-5H-dibenzo[a,d]cyclohepten-5-ylidene)piperidine

Solvents

ethanol

Conditions

Workup

1. 1
   Temperaturerefluxed for 16 hours
2. 2
   OtherThe solvents are removed by evaporation on a rotary evaporator
3. 3
   workup.DISSOLUTIONThe residue is dissolved in chloroform
4. 4
   Washthis chloroform solution is washed with sodium hydroxide solution, water
5. 5
   Dryingdried over magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   OtherEvaporation of the chloroform from the filtrate
8. 8
   Othergives 0.88 g
9. 9
   Temperatureis cooled
10. 10
    OtherThe white crystalline material that precipitates
11. 11
    Filtrationis collected by filtration
12. 12
    Otheris recrystallized from acetonitrile
13. 13
    Otherto give 0.67 g

Procedure

A solution of 0.86 g. (0.003 mol) of 1-methyl-4-(3-bromo-5-hydroxy-5H-dibenzo[a,d]cyclohepten-5-yl)piperidine in 30 ml. of trifluoroacetic acid and 15 ml. of trifluoroacetic anhydride is stirred and refluxed for 16 hours. The solvents are removed by evaporation on a rotary evaporator. The residue is dissolved in chloroform, and this chloroform solution is washed with sodium hydroxide solution, water, dried over magnesium sulfate, and filtered. Evaporation of the chloroform from the filtrate gives 0.88 g. of a yellow oil. This oil is dissolved in a minimum amount of absolute ethanol, treated with ethanolic HCl, and is cooled. The white crystalline material that precipitates is collected by filtration and is recrystallized from acetonitrile to give 0.67 g. of (±)-1-methyl-4-(3-bromo-5H-dibenzo[a,d]cyclohepten-5-ylidene)piperidine hydrochloride.

Source