[http://www.angelfire.com/scifi/WizardX/index.html (http://www.angelfire.com/scifi/WizardX/index.html)
]
thanks Wiz
[http://science.csustan.edu/stkrm/Recipes/Recipes-Lucas.htm (http://science.csustan.edu/stkrm/Recipes/Recipes-Lucas.htm)
]
[http://nlfaculty.dcccd.edu/logan/slides/chapter10/sld026.htm (http://nlfaculty.dcccd.edu/logan/slides/chapter10/sld026.htm)
]
Also:
Anhydrous Acids and Lewis Acids
Lewis acids are those which cannot provide a proton to another molecule but clearly react with bases. Like the proton itself, they are clearly in need of electrons. Their love of electrons has resulted in their being called "electrophiles". Although we generally use the term "electrophile" when no H+ is involved, it is also correct to call protic acids "electrophiles"
AlCl3 and FeCl3
Aluminum chloride has a central aluminum atom which has only 6 electrons; like boron in the acidic BF3, it is very electron-deficient. It is one of the stronger and more common Lewis acids used in chemistry. In the presence of alkyl halides (tertiary best, of course) or acyl halides, it can remove the halide to generate a carbocation (why are they stable?) and AlCl4-. The carbocation will react with whatever is available, even add to an aromatic ring. With carbons that are less able to support a positive charge, the aluminum chloride just loosens the C-Cl bond enough to make the carbon positive enough to react with the aromatic ring (and to rearrange as if it were a carbocation). Aluminum chloride is a powerful dehydrating agent as well, although not very selective; partially hydrated (to reduce its acidity) it works very well as commercial dehydrating agent - the antiperspirant aluminum chlorhydrate.
Ferric chloride is the catalyst of choice for halogenating benzene rings. The reaction proceeds like that of alkyl halides with aluminum chloride, namely polarization to remove a halide to form FeCl4-, and thus generating Cl+. An easy way to do this reaction is just to add powdered iron to the reaction and an excess of halogen; the halogen oxidizes the Fe to FeX3 (where X could be other halogens as well) which then catalyzes the reaction.
ROH2+
All oxygen-containing organic compounds, like alcohols, behave as bases in the presence of concentrated aqueous acids or anhydrous Lewis acids. Depending on what else is present, the temperature and the acid concentration, alcohols can be converted to ethers (one water lost for two molecules of alcohol) or alkenes (one molecule of water lost per molecule of alcohol). When acid and alcohol are added to other oxygen-containing compounds like ketones and acids and esters, they share the proton in equilibrium. The protonation of the oxygen makes the carbonyl carbon more susceptible to attack by nucleophiles in each case; however, any nucleophile that you use must be no more basic than the alcohol or carbonyl compound or it will be protonated instead! If just the carbonyl compound, alcohol and acid are present, ketones and aldehydes undergo addition to produce hemiacetals and acetals, although they are easily converted back to the aldehyde or ketone in the presence of water in most cases. With esters, acids and acid chlorides, the final product of reaction with acid and alcohol is an ester (perhaps a different ester if you start with an ester) via an addition - elimination sequence.
HX (HCl, HBr, HI) and Substitutes
The hydrohalic acids are gases and thus the aqueous "concentrated" solutions are not very concentrated; conc HCl, for example, is 35% in water. The high vapor pressure of the gaseous acid over the solution makes these acids very dangerous to work with, because the chances of exposure to the lungs is quite high. They are exceptionally good at corroding metals (my personal hypothesis is that the high vapor pressure is responsible).
Although HX's can be used for substituting alcohols with halide X, all sorts of side reactions occur with tertiary and secondary alcohols (rearrangement and dehydration). Better methods for substitution are: thionyl chloride (SOCl2) or PCl3, and for secondary and tertiary, the Lucas reagent, which is HCl made more acidic and more chloride-rich by a high concentration of the Lewis acid ZnCl2 (the water is now overwhelmed). Conversion of a carboxylic acid to an acid chloride cannot be done with aqueous HCl (the more stable acid is favored), but must be done with anhydrous SOCl2 or PCl3.
Has anyone any knowledge of this route having been attempted in the literature?
UTFSE for 'Lucas' and this comes up: Post 435996 (https://www.thevespiary.org/talk/index.php?topic=7932.msg43599600#msg43599600)
(WizardX: "Lucas Reagent", Stimulants)
You also knew something about the reaction 4-5 years ago: Post 103487 (missing)
(dwarfer: "Re: Why Iodine sub instead of chlorine", Chemistry Discourse) ;)
methymouse
That might work, though it's a bit unclear to me how you iodinate without HI.
Use phosphorus triiodide, PI3, (or a mixture of iodine and phosphorus, red, yellow, or both) in Carbon disulphide, CS2
dwarfer
wiz: can it be chloro-ephedrine?
Yes! But the iodoephedrine has the best leaving group -I
wiz: I guess the CaH2 would MAKE it a super dry ether: would having some water to generate the H2 be of value (with CaO made because of the molar excess of CaH2 {Rhode said the reaction proceeds thru CaO to Ca(OH)2 with a surplus of water only.
Would there be any advantage to pressure?
NO! & NO! Any water in the ether or if the haloephedrine is still in it's hydrate form, eg. haloephedrine.1/2 H2O will predominate the reaction with the CaH2
Post 486546 (https://www.thevespiary.org/talk/index.php?topic=8486.msg48654600#msg48654600)
(WizardX: "Don't give up!", Stimulants)
dwarfer: Don't give up! Work along the line as such.
CaH2 + haloephedrine in a super dry ether.
CaH2 + 2 C6H5-CH(-I)-CH(-NHCH3)-CH3 ==[super dry ether]==> 2 C6H5-CH2-CH(-NHCH3)-CH3 + CaI2
=============================================
Wiz you stipulated a "super dry ether". Can either benzene,
xylene. or naphtha be used?
====================
8) Marvilous Marvin,
stimulated by possibilities,
entranced with dreams,
motivated by hope,
and positively full 0f imagry of the
wonderful contribution he was about to make
to ALL of Mankind:
(parTICKUlarly hisownselfness,)
did approximately the following,
as well as I could see thru the
40X looking glass,
and after decipherig his screams of rage,
an plaintive sobs of self-pity,
after the fool flubbed the deal...
=================
So anyway, looks like he took 6.5 grams of
fake ephedrine (pseudo) and put it in a
250 ML beaker and was intent on adding the
'zact amount of ZnCl2 and HCl
to chlorinate the
6.5 grams,
but upon opening his
tightly-close bottle of ZnCl2,
discovered that the hygroscopic nature
of the material had confounded the HDPE plastic
and slurped enough H2O thru some ?? tiny orifices
to make your basic (<<anti pun..) :)
unmeasured thick viscous
35% HCl brown solution
and the underlying undissolved
but damn solid mass
a real pain in the ass to deal with .
As a matter of fact, after seeing the guy trying
to pry some out with various tools,
I watched him finall go to his drill press
and drill some out.
So an unknown amount of Lewis acid blend was
poured on top of the huge pile of crystals
in the beaker. It didn't dissolve it:
not by a long shot..
A watch glass was put atop the beaker to
minimize splattering..
The beaker was put in a glass measuring cup.
The measuring cup was put inside a large
sealable plastic kitchen-leftover type bag.
The large sealable plastic kitchen-leftover
type bag was put in the microwave.
The microwave was turned on, and the mass was seen
to dissolve into a viscous brown liquid.
the time of irradiation was about 2.5 minutes total:
each time the material was seen to begin to boil,
it was shut off and allowed to cool
for 15 seconds or so.
The bag began to swell, and Marvey,
who has trashed several microwaves,
decided to not trash his latest, and took the
bag, cup, beaker, and liquid outside to cool.
After it had done so, it appears that he
added some cheap-o $8/gal hardware store
alcohols, which is predominantly methyl:
with ethyl mostly # 2, but it varies.
surprisingly dry, it has been found..
He washed the material
in about three 150 ML quantities.,
and filtered it.
He mixed the alcohol with xylene,
and placed it on a stirring hot plate.
As the mixture stirred, he added small pieces of
CaH2, and did so as the temperature rose,
with copius H2 outgassing.
At the elimination of all alcohols at around 90C,
the hydride reaction became almost negligible.
The liquid was cooled, and filtered.
As the .HCl and the Cl were eliminated from the
target molecule, forming an insoluble salt, the
now methamphetamine freebase became intrained in the
Xylene, where, after gassing, it yielded the most beauteous
desoxyphedrine ever you have seen.!!!
this of course, was what the
loathsome Marvin had dreamed in
his vacant head:
and the absence of such a result
was the proximate cause for the
pitiful wailing, caterwauling, and cursing
which subsequently eventuated.
No, the poor dumb fuck got a cloudy white
broken-moleculed mess of extremely small particulate
chunks of god knows what but it wasn't what he was looking for. .HCl salt chunks of it.. elsuckamundomucho
Pretty funny: you would think
he would come to realize that
what he thinks is going to be really suPERB
has likely already been thought about
by somebody who
may actually know what they are doing:
and generally dismissed outright as stupid.
;) Oh well: he seems to have fun in his fantasies.
and it's sure fun watching the poor bastard
carry on like that..
i think likely the microwave treatment raises the
effectiveness of the chlorination so much that the
molecule has Chlorides sticking out in all directions,
and when the calcium comes up it just rips the shit
outada molly-cule.
Isn't that good chemist talk?
"rips the shit outa da 'cule."?? ;D
===================
Maybe somebuddy else has anudder idear??
Maybe a weaker Lewis combo oughta be used??
Howzabout Calcium chloride?
or maybe just 30 seconds at boiling?
who knows.. ::) :P
For real chemists doing real things:
seehttps://www.thevespiary.org/rhodium/Rhodium/chemistry/ephedrine.catalytic.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/ephedrine.catalytic.html)
For nifty models of alcohols, see
http://people.ouc.bc.ca/woodcock/molecule/ (http://people.ouc.bc.ca/woodcock/molecule/)