Has anyone tried AgOTf as a Lewis acid catalyst for cyclization of CBD to d9/d8-THC?
Not yet but now I wanna 
I tried indium, it was ok.
Still not breaking 70% consistently
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What makes this attractive to use as a cat?
For one thing, it is not pyrophoric. Secondly, it seems to have worked very well for a cyclization that is analogous to the CBD → THC conversion:
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That silver triflate is $27/gram on Sigma
Okay cool. Thanks for sharing.
It is not your cheapest catalyst, but can be made from Ag2O and TfOH.
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TIBA isn’t pyrophoric if it’s diluted enough. Oops secret is out.
I did a lot of experiments on this, but in the end I was not interested in making money doing that when distillate is perfectly fine.
I would love for someone to analyze residual aluminum in these synthetic products.
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if there ain’t any oxygen around to let it exhibit its pyrophoric character.
I’m sure any aluminum left over from the reaction could be removed with bentonite. Which is common in labs anyways.
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Thats a pretty dangerous thing to just spill out on a public forum without a good expanation on why and how its safe if its diluted…
When you say diluted enough do you mean diluted in a solution of solvent? What happens when the diluent evaporates and leaves you with concentrated TIBA?
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Chemical synthesis has three phases; the bond making/breaking itself, the workup, and the purification.
I would be quite surprised if people don’t distill their product. I strongly recommend always purifying whatever cyclization product you get by distillation.
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I am sure the comment refers to the quenching of the reagent itself by careful addition of (typically) water to the stirred, and hopefully, chilled reaction mixture.
That makes sense, but doesnt change that fact that his statement could easily lead someone to a dangerous situation without context. and if its the quenching step hes talking about to make it safe what about all the steps leading up to running the process and also while running the process. ’
I’m just a safety sucker that loves to keep my friends alive and claiming TIBA is safe or not pyrophoric is a scary ass claim to share with like minded humans and friends.
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Maybe we could ask @SoStupendous to elaborate?
This thread started pretty harmless, hinting at the fact that there likely exist Lewis acids that rival TiBA in effectiveness. And I never mentioned TiBA until @SoStupendous did.
Obviously I am not advocating that people start ordering AgOTf and set up conversions in an unsafe environment or without proper equipment and more importantly; with some level of understanding of the underlying chemistry.
AgOTf is most definitely not pyrophoric. It is a salt that lends it very well to weighing on a scale. It’s main downside, as is the case with most silver salts, is sensitivity to light.
All this is of course a moot point if it causes too much isomerization and this, I admit, was something that I had hoped to learn without too many side effects.
TiBA is scary and things can definitely go wrong. But there is a published patent attesting to its effectiveness.
Typically, reagents like TiBA rears their ugly heads during transfer, but once in dry solvent and under dry oxygen free atmosphere, they behave as any other reagent.
As to workup of pyrophorics in general, and aluminum reagents is particular, done incorrectly you end up with a mess in the best case.
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It’s been talked about here in the past
This 
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Care to elaborate on your comment @SoStupendous?
I don’t wanna see the very first thread I start get off the rails before twenty comments, I’d like it to stay on topic, that of non-pyrophoric Lewis acids’ utility in cyclization of CBD in general, and AgOTf in particular.
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I mean I never asked for your assumption on what @SoStupendous meant anyways. I was clearly referring to his mention of TIBA being safe if it was diluted.
I would love him to reply and answer that question and give it better context.
I don’t think a thread can be considered be harmless when it mentions TIBA being non pyrophoric.
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That’s true, but that shouldn’t disallow me from an educated guess.
Yes, let’s hope they do. And maybe @FTGLabs can help divert the harmless or not issue to the thread where this has been discussed before.
You are right, but I wrote started pretty harmless. I did not mean any harm bringing up AgOTf. I tried to shut the TiBA crooked track down by a pretty plausible suggestion. Unsolicited (by you), or not. That’s what I did.
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