January 10, 2025, 04:14:47 PM
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Topic: cyclohexene ring attached to benzene & Dihydromorphine/hydromorphone synth quest  (Read 4923 times)

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Offline scapeish

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My first question, that I've been completely unable to find the answer to, is how would a bicyclo compound be named where 10 carbons form two rings, attached through the middle with a bond, i.e. [4.4.0]bicyclo? where one side is a benzene ring and the other side is a cyclohexene ring.  Essentially what would the name of a compound that looks like napthalene but with one side lacking aromaticity completely.

My second question is in regards to the difference in hydrogenation between dihydromorphine and hydromorphone.  As far as I've been able to find, the differences in synthesis from morphine are nonexistant.  From waht I've read, a Platinum or Palladium catalyst, either in a acidic phase or with the catalyst saturated via bubbling h2, will produce either.  but this doesn't seem right to me; i've found a number of sources stating that the gaseous hydrogen is not necessary, only an acidic phase is.  the part I don't understand, why do these same articles describe identical synthesis with two different results.  What are the conditions that would preferentiate the result to hydromorphone (where the hydroxyl group at the 6 position is replaced by a double-bonded oxygen, and the double bond between 7 & 8 position is hydrogenated) or dihydromorphine (morphine molecule where the double bond of the cyclohexyl ring is hydrogenated)?

Offline Dan

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what would the name of a compound that looks like napthalene but with one side lacking aromaticity completely.

1,2,3,4-tetrahydronaphthalene a.k.a. Tetralin

Quote
i've found a number of sources stating that the gaseous hydrogen is not necessary, only an acidic phase is.  the part I don't understand, why do these same articles describe identical synthesis with two different results.

Give references for your sources. Without knowing what your sources are, nobody can comment on their claims.
My research: Google Scholar and Researchgate

Offline scapeish

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Thanks for the response to my first question;

My second question is really just what makes the synthesis difference between dihydromorphine and hydromorphone, from morphine.  I.e. what are the conditions that cause the keto group at the 6 carbon, in addition to the hydrogenation of the 7,8 double bond, rather than only the hydrogenation of the 7,8 double bond.  As far as I can see, catalytic hydrogenation with a h2-saturated catalyst or acidic phase, using the exact same catalysts, result in very different results.  I don't see how this can be possible.  
So, essentially, what would cause the catalytic hydrogenation (with a palladium/platinum catalyst, either in acidic phase or with the catalyst saturated with h2) of 1-hydroxycyclohex-2-ene to form 1-oxocyclohexane rather than 1-hydroxycyclohexane.

Offline Dan

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*sigh*

Where are you getting these procedures from? Again:

Give references for your sources. Without knowing what your sources are, nobody can comment on their claims.

You say you have a "number of sources" that you claim show "identical synthesis with two different results". Why are you avoiding telling us what these sources are?

So, essentially, what would cause the catalytic hydrogenation (with a palladium/platinum catalyst, either in acidic phase or with the catalyst saturated with h2) of 1-hydroxycyclohex-2-ene to form 1-oxocyclohexane rather than 1-hydroxycyclohexane.

The first reaction is a hydrogenation, the second is an isomerisation of an allylic alcohol to a ketone - not an overall reduction.

It is very difficult to answer the question because you have not given enough information on the conditions and reagents.
« Last Edit: April 28, 2011, 04:10:48 PM by Dan »
My research: Google Scholar and Researchgate

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