Hilski
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Question about secondary alcohols as HCL salts
This might seem like a dumb question, but I was wondering if having an alcohol (and alkaloid in this case) in HCL salt form, as opposed to a freebase,
would change anything in a Jones oxidation?
For example, 1ml Jones Reagent will oxidize ~.004 moles of an alcohol. If the alcohol were in salt form, would the extra added mass of the HCL need
to be taken into account when calculating the molar amounts of reagents needed for the oxidation? If so, how would one calculate the ADDITIONAL
amount of Jones Reagent that would be necessary to oxidise the HCL form as opposed to the freebase form?
Sorry if this questions sounds retarded.
Thanks in advance.
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not_important
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OK, if I am understanding what you are asking, is "H. has an amino alcohol that they wish to oxidise using Jones reagent. The compound is in the form
of the amine salt with HCl; how does this affect the calculation of molar amounts?"
Yes, if you are weighting the amine salt you must include the contribution from the HCl, the compound is that much more massive than the free amine.
A first I was trying to figure out "alcohol salt with HCl".
You are going to have some problems with this, namely the formation of chromyl chloride : CrO2Cl2. A standard preparation of chromyl chloride is to
react HCl with CrO3, or a dichromate with HCl or NaCl and concentrated H2SO4. This is going to shoot you molar calculations to bits.
It might work if the amine sulfate was used, same type of adjustments for MW. However, I don't know how a primary or secondary amine function will
take to Jones reagent.
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Hilski
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| Quote: | | This is going to shoot you molar calculations to bits |
Aaaack. That's what I was afraid of.
Thanks for the reply. You answered my question exactly, despite my bass ackwards terminology.
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not_important
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You could convert the hydrochloride to the sulfate or phos[hate, neither of which should cause problems with Jone's reagent.
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