Sciencemadness Discussion Board

TiCl4 substitute

divinyl - 12-7-2019 at 03:23

In the patent called "Industrial preparation method of midazolam" which can be found here , they use TiCl4 in all examples, except for Example number IV, in which they use ZnCl2. Since they use different reactants in every example but always use TiCl4 in each of them(except Ex IV), I woundered what catalyst could be substituted for TiCl4. They mention that other catalysts(e.g. Lewis acids) could be used instead. I know that TiCl4 has special properties and there are many reactions which at least call for TiCl4 and I seem to remember that it is a great catalyst for eneamnine formation.
My question is: Could I use AlCl3, ZnCl2, SnCl4 etc instead?
I guess that ALCl3 would be the best alternative(if so, what about AlI3?).
I base this on this paper where they compare different Lewis acid catralyst for different reactions.
Which catalyst would you recommend instead of TiCl4? Maybe I am wrong with my guess of AlCl3...
Thanks!

clearly_not_atara - 12-7-2019 at 12:52

TiBr4 from Ti + Br2

divinyl - 13-7-2019 at 10:15

Thanks foir the reply. I have something in the back of my head, that TiCl4 and TiBr4 are faar superior to TiI4, but I can't seem to recall where I read that(could it be that iodine is less electronegative thatnBR and Cl.
Are there any other promising catalyst, except Ti based ones? (They at least use ZnCl2 in one example).

Another question is the workup: They call for hydrolysis. Is this done with staight H2o (in the cas of TiCl4, alot of HCl is given off or do they mean an acid hydrolysis?

Chemi Pharma - 13-7-2019 at 13:04

Synthesizes TiCl4, if it's difficult for you to purchase it, is not so difficult as it seemed in the past. I found a patent that's use any titanium salt to produce an alkaly chlorotitanate, which is thermaly decomposed at relative low temperatures producing TiCl4.

I've posted the patent at General Chemistry Section. Look at here: http://www.sciencemadness.org/talk/viewthread.php?tid=20124&...



[Edited on 14-7-2019 by Chemi Pharma]