Ketamine synthesis
- Thread starter G.Patton
- Start date
cas 74-89-5 or CAS 593-51-1 and use procedure from step 10 to get methylamine gas.
Where did you read about sodium bisulfite in this step? You don't need to use desiccant.
Where did you read about sodium bisulfite in this step? You don't need to use desiccant.
What don't you understand there? or what do you want to heat? You have to wash the reaction solution with aq sodium bisulfite and than evaporate organic solution. This washing reduce amount of bromine excess
You can set a timer for 72 hours or use TLC to check reaction completion.
I already answered you.
You can set a timer for 72 hours or use TLC to check reaction completion.
I already answered you.
8. o-Chlorophenyl cyclopentyl ketone.
To the thus obtained Grignard soln there’s added 48 g o-chlorobenzonitrile and the mixture is stirred for 3 days at RT. It is then poured into a mixture of ice/NH4Cl, with addition of some conc. aq. NH3 and left at ambient temp until all ice melts. The ketone partially floats, partially goes to the bottom. It’s extracted with benzene (Use 100 mL x2 times). The yields fluctuate, but rarely drop below 55%.
Step 2: alpha-bromo (o-chlorophenyl)-cyclopentyl ketone.
To 21.0 g of the above ketone is added 10.0 g of bromine in 80 ml of carbon tetrachloride dropwise at 0 °C. After all the Br2 has been added, an orange suspension forms. This is washed with a dilute aqueous solution of sodium bisulfite (~65 mL x2 of 10% solution) and evaporated to give 1-bromocyclopentyl-(o-chlorophenyl)-ketone, bp 111-114 °C (0.1 mm Hg). Yield is ~66%. This bromoketone is unstable and must be used immediately. Also, attempts to distill it at 0.1 mm Hg lead to some decomposition, so it should be used without further purification.
To the thus obtained Grignard soln there’s added 48 g o-chlorobenzonitrile and the mixture is stirred for 3 days at RT. It is then poured into a mixture of ice/NH4Cl, with addition of some conc. aq. NH3 and left at ambient temp until all ice melts. The ketone partially floats, partially goes to the bottom. It’s extracted with benzene (Use 100 mL x2 times). The yields fluctuate, but rarely drop below 55%.
Step 2: alpha-bromo (o-chlorophenyl)-cyclopentyl ketone.
To 21.0 g of the above ketone is added 10.0 g of bromine in 80 ml of carbon tetrachloride dropwise at 0 °C. After all the Br2 has been added, an orange suspension forms. This is washed with a dilute aqueous solution of sodium bisulfite (~65 mL x2 of 10% solution) and evaporated to give 1-bromocyclopentyl-(o-chlorophenyl)-ketone, bp 111-114 °C (0.1 mm Hg). Yield is ~66%. This bromoketone is unstable and must be used immediately. Also, attempts to distill it at 0.1 mm Hg lead to some decomposition, so it should be used without further purification.
benzene has lower density hence it will on top
You got reaction mass after reaction and there is excess of Bromine. You add water solution of sodium bisulfite to reaction mass, shake it, divide layers. Repeat procedure. You have to discard water layer (with sodium bisulfite) after washing. NaHSO3 bounds excess bromine from reaction mixture after reaction. Do you understand?
You got reaction mass after reaction and there is excess of Bromine. You add water solution of sodium bisulfite to reaction mass, shake it, divide layers. Repeat procedure. You have to discard water layer (with sodium bisulfite) after washing. NaHSO3 bounds excess bromine from reaction mixture after reaction. Do you understand?
No, your extraction with benzene means that your product will be extracted (located in benzene) by benzene. Than you will work with extract (benzen+product).
no, you have to evaporate sln. after both washing procedures...
no, you have to evaporate sln. after both washing procedures...
Only once, no more. Do you understand procedure? Read several times to understand better. I have already written this info. There is clearly detailed explanation.