I need comments and corrections for the 5CL synthesis process

[ChillhubVN]

Hi everyone,
I’m in the process of preparing 500g of 5CL and have the following chemicals on hand:
1. 1H-INDAZOLE-3-CARBOXYLIC ACID METHYL ESTER (CAS 43120-28-1) - 0.5kg
2. N,N-Dimethylformamide (DMF) (CAS 68-12-2) - 1.5kg
3. 5-Bromo-1-pentene (CAS 1119-51-3) - 0.5kg
4. Potassium carbonate (CAS 584-08-7) - 0.5kg

I’m a bit concerned about the process and would really appreciate your advice to ensure everything goes smoothly. Here’s the procedure I’m planning to follow:
**Steep 1:** Dissolve 0.5kg of the main precursor (1H-Indazole-3-Carboxylic Acid Methyl Ester) in 1.5kg of DMF at room temperature until homogeneous.
**Steep 2:** Increase the temperature to 70-80°C (planning to use around 75°C), then add 0.5kg of potassium carbonate to the solution and stir for 2-3 hours.
**Steep 3:** After 2-3 hours, when the potassium carbonate has mostly dissolved, add 0.5kg of 5-Bromo-1-pentene to the mixture. Maintain the temperature and stir for another 2-3 hours.
**Steep 4:** After stirring, cool the solution to room temperature. Slowly pour the mixture into 10L of ice water, stirring quickly to induce crystallization.
**Steep 5:** Filter the solids and rinse with a saturated NaCl solution to remove any water-soluble impurities.
**Steep 6:** Dry the product by hanging in a cool place (25-35°C) or placing it in the refrigerator.

I have a couple of specific questions:
- What should be the appropriate stirring speed (rpm) for each step?
- Can I use a magnetic stirrer instead of an overhead stirrer for this process?

Any insights or suggestions would be greatly appreciated. Thanks in advance for your help!

 

[HerrHaber]

About specific questions: I have no clue RPM wise, but for sure overhead stirring is advised vs. magnetic in this case (at least at the precipitation step the volume is large and if solids form, the stirbar may get stuck).

 

[ChillhubVN]

Thank you for your advice

 

[ChillhubVN]

Is there any problem with the steps you followed?

 

[HerrHaber]

It's not the freshest topic in my mind and I do remember to largely agree please master this on a small and manageable batch size as I promise if you prove i can get you thank me and benefit quite a lot. As I think of chemistry being somewhat sacred, I need you to deserve the profitable scale that I only teach people how to work with. I may find offensive understanding that you are quick to make a buck and stick around to deserving the results of your doings as big inexperienced handler's batches will get you to your place eventually and these exact products you go for tend to be really unforgiving. Big fuck up is at least wastefully expensive and troublesome in all ways you didn't think of.

 

[HerrHaber]

You present yourself as a future chemist on a good track and you are invited to value my statement as I tend to discourage anyone asking to take for granted and be stubborn on his personal hocus-pocus view. Accept the fact that you need to climb your way and the first steps are the slowest and you already did a few... not sure about where you are as over regarding a basic concept can become destructive. Cheers!

 

[ChillhubVN]

I am very touched by your comment. I see your passion and respect. I love chemistry but I'm not good at it and life doesn't allow me to stumble many times so I came here to ask

 

[renzox7]

Can someone explain this step "Filter the solids and rinse with a saturated NaCl solution to remove any water-soluble impurities." what saturated NaCI solution means? and how to do it correctly.

 

[lutte123]

First of all, you are trying to use wrong precursor. INDAZOLE-3-CARBOXYLIC ACID METHYL ESTER will not produce your desired product. Search this forum, you will get the asnwer you looking for...

 

[ChillhubVN]

Can you tell me what I'm missing?

 

[Topnoidssupplier1]

I haven't cooked yet, waiting for the stove and utensils

 

[ChillhubVN]

I haven't cooked yet, waiting for the stove and utensils

 

[WillD]

This recipe will only give 2/3 of the desired product.

 

[Ecko6ap]

and which recipe will give the maximum yield of the product?