New here. but am hoping to learn; D10 to HHC , isomer favoritism compared to from D8 or D9 ? am i onto the right idea or naaive?

new here. but am hoping to learn; D10 to HHC , isomer favoritism compared to from D8 or D9 ? am i onto the right idea or naaive ?

i was un able to find a tek forum/category… please move to proper area if i messed up.

Since D10 has the 1a carbon in a planer pi bond; hydrogenation would make isomer concentrations different than from D9 or D8 ?
with D6a10a (not found pure though, “ usually contains 50-80% Δ6a10a THC with the rest being CBN, Δ8 THC, and/or Δ10 THC. “)
there are both directional H bonds at 6a and 10a that could reform in different preferences;
not to mention that with D10 “ Two enantiomers have been reported in the literature, with the 9-methyl group in either the (R) or (S) conformation” wikipedia [ 1. Srebnik M, Lander N, Breuer A, Mechoulam R (1984). “Base-catalysed double-bond isomerizations of cannabinoids: structural and stereochemical aspects”. Journal of the Chemical Society, Perkin Transactions 1: 2881–6. doi:10.1039/P19840002881.
2. ^ WHO Expert Committee on Drug Dependence Critical Review. Isomers of THC (PDF) (Report). World Health Organization. 2018. ]

long story short

with D10 hydrogenation to HHC , (3 isomers ? )
and with D6a10a hydrogenation (assuming obtainable let alone affordable…) to HHC with maybe a different combo of the 3(?) HHC isomers (enantiomers or rotamers?)
and whatever enantiomers the D10 or D6a10a enantiomers would also influence that if the feedstock had different ratios.
in the case of the 50-80% D6a10a, would that then be reasonable, being that any D10 and D8 would also hydrogenate to HHC but also that the CBN would reduce to something; a thc ? then further reaction maybe gets it to HHC or no because that’s a problem of over hydrogenating HHC and or that the D8 or D10 reaction rate differences to the 6a10a or visa versa end up making it that the reactionflash has to cease at an endpoint that HHC is not further reduced ?

idk, i’m a very curious person and an amateur chemist, looking to learn for my own experience and economic access to things i use/need/plan to diy.


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You might have some fun with this one

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There will be similar stereo chemistry considerations when you start with d8, d9, d10, or d6a10a. There’s another stereo center at the 10 and 6a10a carbon which would cause some new HHC isomers not normally formed by d9 and d8.

To add to that headache d10 and d6a10a are usually a mixture of isomers at the 9 carbon already. So if you start with d10 you’ll end up with 2x the stereoisomers in the final product as d8 and d9. If you start with d6a10a you could end up with 8 different isomers


but you can still huff it straight from the reactor right?

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There will be four distinguishable isomers. Δ6a(10a) exists as a pair of an enantiomers. The 9S isomer is the slightly more active, I think. There’s a nice little Hollister paper where they evaluate 9R- and 9S-Δ6a(10a) in volunteer mid 20s males.

In any event, addition of H2 over the 6a-10a double bond can occur in two ways, 2 x 2 = 4.


You will get four different isomers. You start out with a pair of mirror images. In each of those images, H2 can be added from two sides, the two sides differing in whether the 9-methyl points to the same side or not. There will be some, maybe small, stereofacial preference of H2-addition. You will have with something like 60:40 of two pairs of enantiomers assuming you start with any racemic Synhexyl homolog, is my guess.


The 60:40 guess above was for Δ6a(10a). For Δ10 the selectivity might be better, 70:30.

All the products from Δ6a(10a) would have the “unnatural” cis ring fusion and I expect little to no activity.

In case of Δ10, product distribution is harder to predict, and depends on what 9R/9S ratio of Δ10 you start with. Some of your product will include the undesired cis ring junction. If there’s a silver lining, it may be that absolute stereochemistry at 6a is preserved when adding H2 to Δ10.


whoah ! that’s fascinating ! imagine that

all this though, keeps the alkyl chain geometry though ? i mean, the mirror isomer of it with the benzene plane face to view like a donut hole, and the first carbon is planer to the ring coming straight out; and then the chain goes in or out of the page., and depending keeps like a stair or folds in two at a carbon into or out of the plane more severely; at least when tinkering with alkyly chains and molecules on iSpartan, which isn’t entirely accurate.

Close enough…

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When H2 gets added to a double bond, both hydrogens are added to the same side of the double bond. A double bond has two sides which H2 can be added to. Sometimes there’s a small differences in facial selectivity, sometimes virtually only one product is observed.


You’re right I meant to say 8!

Meant to say 8 but I didn’t realize that H2 is always added to the same side. You are correct that 4 would be the number

ehhhh yeah idk it’s like yeah and no, not really but it’s very useful; i can compare to mo-cubed on android with quantum chemical calculations to reference and hopefully get desmond/maestro up and running on a linux hdd/ssd and learn how to use it; but real life is seemingly always different in reality; with x-ray crystallography showing what is measured, but also in a form like in vitro vs in situ; or rather what i mean to say is i’m am thinking about alexander shulgin writing that the nature of compounds and receptors is elusive and shows different things depending on how it is looked at; so by shining a light in the darkness, that it changes the nature of what you see. i like that analogy a lot and believe it is all rather complex with receptors being morphable (dr. david e nichols pondered of it being the case with the 5HT2A receptor, and in cannabis it seems to be the case i’ve gathered…,and stuff we just don’t have an idea of yet.

You should have meant to say 4!

Assuming metal catalyzed addition of H2, the two hydrogens will be added from the same side.


hey, just in general, not about thc; is it Flourine that also adds to the same side, cis rather than trans of Chlorine etc. ? catalyst selection maybe to bais (in D10 etc. to HHC) ?

Edit: i mean on benzenes/substituted phenyl…

I’m a bit lost. Over an alkene I think that fluorine and chlorine both add trans

I can close to guarantee that any decent molecular mechanics based approach will make you appreciate why which side of diastereofacial addition of H2 to a double bond is favored.

iSpartan is very much good enough.


I can get only speak of bromine which gets added trans via a bromonium intermediate.

X-X is different from H-H, and more so as you go down the halogen column. It’s due to better polarizability of higher electron count halogens.