9R HHC active vs 9S HHC inactive

Good Morning everyone.

Had an interesting conversation with some of my European clients about HHC. As we know, higher potency is more desirable when purchasing HHC and having no heavy metals is equally as important.

This client in Spain brought up a chart showing that there are two HHC varients: 9R-HHC which is active and 9S-HHC which is inactive. My question is do all liters of HHC have this 1:1 (or close to a 1:1) ratio and does it matter? Does the inactive 9S HHC still have effects on the user?

I found this article on Leafly that touches on the subject. They state that the remediation process would essentially but to costly to justify. With that being said, I believe it implies that 9S does nothing for the user, since they touched on remediation/separation.

Please let me know your thoughts and once we get the info, I will write an informative article about it.

best, Jon

www.bonavoluntate.com ← please smash this link to help my SEO!


Mechoulam reports different ratios of each isomer based on what kind of thc you start with

I’m pretty sure most are actually getting around 50/50 regardless of whether they start with d8 or d9 disty


Is most d10 racemic in the same proportions? If d10 is skewed to one or the other, that would be a better starting point since the hydrogenation doesn’t have two options when saturating the planar double bond attached to the methyl group

Also I haven’t ran this reaction and probably never will, my hydrogenation is limited to 200mL flasks with a balloon many years ago. Can you push the products by running an ice cold reaction vs rt vs warm?

Edit: lol @ the sign out on the main post…

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D10 is like 90/10 (90% 9R /10% 9S :wink: )

The 10a proton deprotonate from one side causing the R isomer to form more

This is something I’ve thought about before for making hhc

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Does 9S-HHC carry any active effects or is it truly “inactive” as the name suggests?

The 9S diastereomer is not totally inactive, maybe 5-10% that of 9R according to the 1971 PNAS article from Mechoulam’s group.

From a practical point of view, contribution of the 9S epimer to a 1:1 mixture’s activity is negligible.


The diastereomers would have to be separated by chromatography and is probably a tough separation.


There are a couple of issues with this strategy:

  1. The 10-10a double bond is more hindered than both the d8 and d9 double bonds, possibly making hydrogenation more sluggish.

  2. Facial selectivity may be much influenced by chirality at C9. This could be a good thing.

  3. Hydrogen could be added either from the same side as the 6a hydrogen is pointing, making an unnatural cis ring junction. Hydrogen would have to be added from the other side to arrive at the natural trans configuration at the ring junction.

I think the last issue is the bigger one. I think that the predominant products will be the ones with a presumably inactive 6a-10a ring junction.


Would high pressure hydrogenation answer point 1?

Interesting points as always, thank you


That could be one way of overcoming obstacles. Or using a better catalyst than the usual palladium on charcoal.


Drawn by yours truly using information from one of Mechoulam’s many papers.


Rainey nickle? :wink:

Just kidding

What would you consider a better catalyst?

I was gonna mention Raney-Ni but changed my mind.

What came to mind was Wilkinson’s catalyst, but reminding myself of its structure, it looks terribly bulky.

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Paper mentioned in the article:

I’ve read of formic acid being used as a hydrogen donor.

You’re still limited by the catalyst, I believe.

Thanks for the link!

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Do you think exposing a Pd doped oil in water emulsion to ultrasound would affect the rate of catalysis?

… works in mysterious ways but more in a macro as opposed to a micro (atomic level) way, I think …

Triggering pchem nightmares

Rh is dumb expensive now a days, though it looks to have fallen from it’s 25k+ high this year. Something something buy the dip


This was the article that I was reading that prompted the question.

You are the man! Hope it was OKAY to use it, if not please let me know.

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