Morning everyone (to all European readers).
I've read many people running into a divided list of problems in the synthesises of 3-CMC by using precursor 2-bromo-3-chloropropiophenone.
First of all, this is in Liquid form. And it is transparant.
I personally myself, did the reaction with
5 Litres 2b3c
17.5 Litres Ethyl Acetate
7.5 Litres 40% MMA (monomethylamine in H2O)
5 Litres of 2b3c is added to 17.5 Litres of Ethyl Acetate in a room temperature setting. This solution is stirred well until the precursor is fully dissolved.
7.5 Litres of 40% MMA is added slowly in proportions, keep a close eye on the temperature.
My observings: the temperature has risen to 50° Celsius. The mixture started to turn yellow, then orange/yellow, then orange/red, afterwards dark red. Until a point that it was dark red almost black. Now after 3 hours of stirring, suddenly the temperature has risen until 53-55 °C, the color is changing. It got lighter. First yellow/orange and then a dark orange or an amber color was seen for 30 minutes. It started decreasing into a dark red color again. Temperature was still at the same level so exothermic reaction was still ongoing. After 5 hours of stirring the reaction was done. It got very dark red & black. (Note, temp did never reach any higher than 55° Celsius. Note 2: the MMA was added slowly. Note 3: the precursor was tested at an NMR lab, 98+ purity)
Now, Baking Soda solution in water was added. Stirred. The mixture became light orange. After standing for a while there are 2 layers. Funny enough the upper layer is very dark, and 5.5-6.0 Litres. The lower layer is orange. It seems separation is not going well. Yet everything was done as described in the 3-cmc synthesis. I have read almost all 3-cmc threads on this forum. And everyone faces the same problems:
Problem 1: a very dark red or almost black end product of solvent + 3-cmc freebase
Problem 2: crystalization in the freezer is not working, I see a lot of crystalizations where the solvent (dcm or ea) is slowly evaporated in open space. This is not safe/practical.
Problem 3: the yield, I've read a lot of 30-40% yield messages.
I suggest to work together to make this synthesis practical for everyone, with a high yield. Please try to be helpful in this thread. And lets share knowledge together
PS: the picture shows the current state, after the water + baking soda wash.
I've read many people running into a divided list of problems in the synthesises of 3-CMC by using precursor 2-bromo-3-chloropropiophenone.
First of all, this is in Liquid form. And it is transparant.
I personally myself, did the reaction with
5 Litres 2b3c
17.5 Litres Ethyl Acetate
7.5 Litres 40% MMA (monomethylamine in H2O)
5 Litres of 2b3c is added to 17.5 Litres of Ethyl Acetate in a room temperature setting. This solution is stirred well until the precursor is fully dissolved.
7.5 Litres of 40% MMA is added slowly in proportions, keep a close eye on the temperature.
My observings: the temperature has risen to 50° Celsius. The mixture started to turn yellow, then orange/yellow, then orange/red, afterwards dark red. Until a point that it was dark red almost black. Now after 3 hours of stirring, suddenly the temperature has risen until 53-55 °C, the color is changing. It got lighter. First yellow/orange and then a dark orange or an amber color was seen for 30 minutes. It started decreasing into a dark red color again. Temperature was still at the same level so exothermic reaction was still ongoing. After 5 hours of stirring the reaction was done. It got very dark red & black. (Note, temp did never reach any higher than 55° Celsius. Note 2: the MMA was added slowly. Note 3: the precursor was tested at an NMR lab, 98+ purity)
Now, Baking Soda solution in water was added. Stirred. The mixture became light orange. After standing for a while there are 2 layers. Funny enough the upper layer is very dark, and 5.5-6.0 Litres. The lower layer is orange. It seems separation is not going well. Yet everything was done as described in the 3-cmc synthesis. I have read almost all 3-cmc threads on this forum. And everyone faces the same problems:
Problem 1: a very dark red or almost black end product of solvent + 3-cmc freebase
Problem 2: crystalization in the freezer is not working, I see a lot of crystalizations where the solvent (dcm or ea) is slowly evaporated in open space. This is not safe/practical.
Problem 3: the yield, I've read a lot of 30-40% yield messages.
I suggest to work together to make this synthesis practical for everyone, with a high yield. Please try to be helpful in this thread. And lets share knowledge together
PS: the picture shows the current state, after the water + baking soda wash.
