Why are these not discussed more? The 14-esters are supposed to be extremely potent, ranging from approximately 10x morphine with the acetoxylated version to over 100x morphine for the cinnamoxylated version. SWIM dreams of putting an end to the stranglehold the cartels and Big Pharma have over the supply of opioids in this country. This seems to be a good way to do it. The cinnamoxylated version could easily be made by mixing oxycodone and cinnamic acid (air oxidation of cinnamon oil) with a coupling reagent such as DCC or PyBOP. Making the cinnamic acid anhydride is trickier. Chances are you would have to prepare cinnamoyl chloride first and react that with sodium cinnamate. You can prepare the mixed anhydride by refluxing with acetic anhydride and distilling off acetic acid (credit goes to jon), but who knows if this will actually produce our desired ester - it may just produce the acetoxylated version and free cinnamic acid...

Fortunately for this reaction, it is extremely difficult if not outright impossible to force an elimination at the 14-OH. I don't have the reference handy at the moment but some bastards in the 1930s tried to do it using all kinds of reagents, and the only one that did anything was P2O5, which outright destroyed the molecule. Even phthalic anhydride did nothing. So, dreamers can happily reflux away with their acid anhydrides to drive the reaction to completion with little concern of elimination side products. 10x morphine (acetoxylated) and 20x morphine (propioxylated) is nothing to laugh at, especially considering that these anhydrides can be easily be prepared from their anhydrous salts, sulfur, and chlorine gas, and that a little will go a long way. Oxycodone is widely available as a precursor and cold water extraction is simple. Is the only reason there's so many shake 'n' bake meth labs and no oxy labs because oxy makes you pass the fuck out into a dreamless sleep? This seems entirely feasible. 

What was disappointing about the oxycodone esters? Were they not as potent as previously reported in the literature, or were the effects qualitatively poor? Interesting about the enol acetate - I saw this prep in the literature you speak of (using NaOAc) but didn't think it'd make too much of a difference given that 1+1 in the opioid world is often 1.  How would you compare the 14-acetoxylated enol acetate version of oxycodone to the 14-acetoxylated codeinone? If I remember correctly, the esters of codeinone are somewhere around 5-10x more potent...

What's your experience with the enol acetate of hydrocodone? Is there a big difference between the one made with acetic anhydride vs propionic anhydride? I thought thebacon was only slightly more potent than hydrocodone itself, but I suppose the effects could qualitatively be better? It's strange and interesting that with the esters, the 7,8-unsaturated compound is preferable to the 7,8-saturated compound when the 14-hydroxylated compound is better with 7,8-saturation, along with dihydromorphine etc...

Thanks for the feedback!

Which 14-ester of oxycodone did you try? So qualitatively the effects were similar to oxycodone, just not as potent? What was the route of administration? I know you're one to use the needle, so I assume you tried it the same way the rats did.

Perhaps it's a bioavailability issue. In rats I believe even the acetyl ester was at least 5x morphine, but this was IV. And if I remember correctly these esters aren't easily hydrolyzed in the lab, but who knows what happens in the body. Either way Assyl doesn't use needles, and the information is much appreciated on potency via insufflation.

I posted some suggestions on alternative methods of acylation on The Collective and had my post deleted and was silenced for it. If you could provide some feedback on these ideas it would be fantastic.

There was a patent from 1927 posted: hxxps://the-collective.ws/forum/index.php?topic=11618.msg52509#msg52509
I imagine you may have seen this. It claimed that anhydrides could be produced from NaPO3 (sodium hexametaphosphate) and the acid. If there's any truth to this (I don't trust patents much), it would be interesting to try producing the anhydride in situ for acylation.

Ketenes are the most potent acylating agents known: (to the best of my knowledge)

Look at the reactivity of ketene section:
hxxp://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/special2.htm

Enol esters from carbonyl compounds and ketenes:
hxxp://pubs.acs.org/doi/abs/10.1021/ie50472a021 (on page two for those with journal access)
hxxp://onlinelibrary.wiley.com/doi/10.1002/anie.200501849/abstract

Amides and esters from ketene:
hxxp://web.mit.edu/chemistry/fugroup/pdf/gcf_130.pdf

Acylation of aromatic substrates with ketene:
hxxp://www.nrcresearchpress.com/doi/abs/10.1139/v80-187

Acetylation of glucose using ketene from a ketene lamp:
hxxp://pubs.acs.org/doi/abs/10.1021/ja01871a057

Acylation of steroidal alcohols including tertiary alcohols:
hxxp://ip.com/patent/US3374230

How was your propionic anhydride prepared? There is a well known method (which again I'm sure you're aware of) using propionate, sulfur and chlorine documented on SM, but I'm curious if you're using the method you previously mentioned (hydrogen sulfate + heat --> Na2S2O7 + acetate/propionate --(distillation--> anhydride).

Great! Is your oven unusually hot or anything? Assyl believes his hits around 550F (287C). Doesn't bisulfate decompose at 315C? I guess the loss of water does proceed at lower temperatures, just slower and not to total completion, but as you said, these reagents are so cheap that yields are largely meaningless, and besides, if there's some bisulfate left, it'd help produce some propionic acid to catalyze the reaction as a solvent (as you suggested elsewhere). Also, is ventilation required? Elsewhere you've stated that you did this outside over a charcoal fire on a cast iron skillet, and others have claimed to have observed H2SO4 fumes spewing out of the molten bisulfate...

Hey, here's some additional food for thought: is it actually necessary to distill the propionic anhydride? Why not add toluene and filter? Acetic anhydride is soluble in toluene, so Assyl imagines propionic anhydride would be as well. All of the salts are obviously not going to dissolve at all. This would also offer a solution to the problem of how to produce cinnamic acid anhydride (instead of just the mixed anhydride formed by refluxing with another anhydride). Heat sodium cinnamate with the pyrosulfate, then add toluene and filter...

Are you saying cinnamic acetic acid anhydride decomposes to cinnamic acid anhydride and acetic acid anhydride upon heating, the latter being removed via distillation?

Is this a gas oven you're referring to? Reason I ask is gas ovens have the heating element concealed below a metal plate, while electric ones have the coil directly exposed. It may be hotter near the electric coils, I don't know. Either way, should just test this rather than speculating endlessly! And besides, there's another post somewhere that states you can simply suspend the pyrex dish over an electric hotplate and get good results.

 Doesn't seem to me like any oven is going to hit the temperature necessary to start spewing SO3. 400C = 750F, and I've never heard of an oven getting that hot unless it was a brick bread oven or a blast furnace. Sounds good.

You may be right about the shortcuts. Just occurred to me that pyrosulfate probably will produce toluenesulfonic acid upon addition of toluene. Just trying to think of ways to make this as accessible to the masses as possible... the elves have never been too lazy to perform a distillation.

One issue that would be good to be addressed is OTC acquisition of cinnamic acid. Perhaps the 14-cinnamoxy esters of oxycodone are still worthwhile. Leaving some cinnamon oil out in a dish yielded a tiny, pitiful amount of crystals. Supposedly cinnamaldehyde is oxidized easily by air to cinnamic acid, but the elves did not observe this. Instead the oil just gradually volatilized and was gone. Not sure but it seems it may be a tricky one, given by the double bond present in this molecule... obviously the oxidizing reagent must be tuned to avoid touching this moiety.

hxxp://pubs.acs.org/doi/abs/10.1021/j150359a005

i've seen cinnamic acid sold by purveryors of fine chemicals it's not an aquisition issue
yes that is exactly what happens acetic anhydride makes a mixed anhydride cinnamic acid being present in excess will react with the mixed anhydride and acetic acid distilled off pushing that equilibrium to the right.
a standard electric oven with the rack set next to the coil make sure it does'nt contact the coil or it will shatter violently.
if it gets too hot just adjust the oven rack to lower the temperature that simple.

Here are all the papers that has been cited in this thread

the p-ester lasts a good long time di-p-morphine about 16 hours i dunno about the enol ester.

it lasted maybe 3 hours but i suspect the 6-enol ester has a longer duration i can't really say though.
if you can get morphine then make di-p-morphine it's good stuff.