[jack2020]

hi all
what makes benzodiazepins decomposition? does the 7 membered ring open in moisture or heat? and what is  the product of this decompoition?
thanks for your help

[billnotgatez]

Forum rules require you show some work
please read forum rules

[jack2020]

Forum rules require you show some work
please read forum rules

ok, I tried to synthesize benzodiazepin, after reaction compelation the tlc showed only 2 spot, one of them was starting material and the other was more polar and showed flourcent (may be the product), we didn't have vacum in lab so I heated the mixture to evaporate the solvent, I dissolved the mixture in benzene and peterolieom ether and it was kept in refregerator after 2 days, the TLC showed 2 more spot (ie.4 spot in general) one of these 2 spots was unpolar and the other which was observed in visible region, was prevaded as the bottom of the TLC paper changed color to yellowafter a short time (10min)!!
now I am in doubt that what has happened?

[Arkcon]

I think your initial conclusion, that the ring opened due to moisture or heat, is a fairly good one.  Can you write out a structure, that fits your observations, for us?  That is, you have the initial structure, the ring has been opened, and H₂O has reacted .. how exactly, to produce what, that is more polar?  Specifically what will probably require a mass spec, or maybe even an NMR, but we don't do that for every failed synthesis.

[jack2020]

The product should be sth like diazepam, and can you suggest what is that spot in tlc which pervades or in general, which compounds can show a spot like this, unfortunately I don't have any spectrum at this stage

[Arkcon]

OK, tey to be more clear when you write, so we can help, that is help ... you use most of your knowledge and we give hints, that's how this board works:

The product should be sth like diazepam,

That doesn't mean anything.  Check your spelling, and use the real word.

and can you suggest what is that spot in tlc

No.  I can't.  And I also don't want to do your work for you.  So no, I won't.

which pervades

per·vade:

verb

1.  (esp. of a smell) spread through and be perceived in every part of.

2.  to become diffused throughout every part of

Sorry, but this word you used is meaningless here.  Try again.  Ask what you want, so you can understand what you're asking for, and see if maybe you're asking for too much from us.

or in general, which compounds can show a spot like this

,

In general, no I can't do this.  There's nothing general about this reaction, and nothing specific about a particular spot.  If you've made the product, and you see its impure and you want to conclude that its decomposed, then you have to show how it happened.

unfortunately I don't have any spectrum at this stage

I figured.  So, why not begin this problem by drawing the structure of your desired product, and your possible contaminant?

[jack2020]

The product is diazepam http://en.wikipedia.org/wiki/Diazepam and the only thing that I guess is ring opening as impurities, I have found in internet that it has a balance with the opened ring form with water, (I mean water can open the ring), unfortunately I can't send attachment may be due to my browser problems,
also I do apologize for my poor English, in explanation about the spot, I meant the spots some how such as benzaldehyde which propagate (hope not to made mistake again) of course my spot (as impurity) propagates much more than benzaldehyde spot on TLC paper.

[zsinger]

Jack,
While I am always happy to answer your questions, it appears to me that you are trying to synthesize/alter drugs of this sort.  You would not be asking some of these questions if you had the proper knowledge to manufacture them.  Not trying to sound snobby, nor am I saying that I do…..I just don't want to hear of any poisonings, deaths, or anything of the matter.  PM me if you would like to chatter privately.
                   -Zack