No,
D10 is like 90/10 (90% 9R /10% 9S 
)
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.
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The diastereomers would have to be separated by chromatography and is probably a tough separation.
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There are a couple of issues with this strategy:
-
The 10-10a double bond is more hindered than both the d8 and d9 double bonds, possibly making hydrogenation more sluggish.
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Facial selectivity may be much influenced by chirality at C9. This could be a good thing.
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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.
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Would high pressure hydrogenation answer point 1?
Interesting points as always, thank you
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That could be one way of overcoming obstacles. Or using a better catalyst than the usual palladium on charcoal.
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Drawn by yours truly using information from one of Mechoulam’s many papers.
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Rainey nickle?
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
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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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Of course.
Let me know if you need advice as to how to make the active diastereomer only.
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Things have definitely evolved since this post 1 year ago.
Noticed a lot of fraudulent things in the market. As well as bad business practices. We are fortunate to be a helping hand while others have followed the cheap, quick, and bad product offers.
I think we are moving in the right direction. Keep it up, everyone.
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I am interested in HHCP and THCP, can you give me a good price.