Isomers

[NueVaaj]

Why can't cis isomer convert to trans isomers or vice versa?

[TonyV]

Can't keep doing your homework for you, answer should be in one of your text books.

[Malachite]

Is this a real conversation starter or are you too lazy to prepare for a thesis/dissertation and you want us to do it for you?

[Malachite]

..whoops, cross post with Tony :-)

[TonyV]

No problems malachite but my views are not the same as all, who think site traffic is king.

[Malachite]

You'll have to be more specific.

[TonyV]

Answer No 2 on this thread Mala.

https://www.theanswerbank.co.uk/Science/Question1643697.html

[Theland]

Really simple. One is a left handed isomer, dictated by the polarity of the underlying protein properties of the molecules, where density is crucial to stability.
Similarly, transisomers are also left handed, but not as reliant on the stability of the proteins, which can become unstable if the density is compromised by agromophormic consequences as described in Vladimir Petrovdkys paper, (1953), for which he won the Nobel prize for Chemistry.
Hope this helps.

[Malachite]

Tony V.
Ok, I get you, but studying is all about encouraging people to think and work things out for themselves isn't it?
When you are studying to be an expert in a specific field, don't you agree that you need to be able to be independently free thinking and able to calculate and work out what to do without recourse to someone else's pre-determined answers?

[TonyV]

When I was studying, long before interweb, would regularly use either college or local library.

[Malachite]

Nice bit of made-up nonsense there, Theland.
Now lets discuss evolution ... ;-)

[Malachite]

Well exactly Tony, we seem to be on the same wavelength, so why the cross-reference to someone who thinks it's wrong to discourage this sort of 'cheating'?

[TonyV]

Probably just "old school" Mala, where I think you gain more from researching and understanding answer than someone giving you answer.
By the way Theland, from depths of my ONC chemistry, think you are getting mixed up, more to do with mirror images of specific chemical formulas.

[theprof]

Who told you that this can't happen? As I understand it, you are currently studying medical science. Here's a clue: investigate the biochemical processes involved in vision. There's one particular chemical pathway that is relevant to your question.
Spontaneous cis to trans conversion and the reverse does occur in organic chemistry but the compounds involved are somewhat obscure and require some research on your part.

[woofgang]

visual purple?

[theprof]

Well researched response there woofgang but it's not quite right. The OP needs to research this further.

[woofgang]

theprof, I did no research....it was a vague memory dredged up from the dear dead college days beyond recall

[theprof]

That's good woofgang. It's surprising what we can all dredge up fron distant memory when the need arises.

[Ianfiat]

Because you can’t rotate pi bonds.
Note, cis and trans are not really used anymore, the correct terms are E and Z

[woofgang]

theprof, it stuck in my mind because I thought it was a neat trick.