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Help me, solvent for my compound

  1. Mar 15, 2009 #1
    I have synthesized new compound containing 2 quartenary amine and 2 long chain ester (dodecyl). However, I get difficulties to find the suitable solvent to my system. My compound just soluble at hot water. Logically, because it has long chain ester, it must be soluble at organic solvent. But, it can't dissolve at almost of organic compound (I have tried it)! Can you suggest me what kind of organic solvent which I must try ? Or can you have logical explanation to my problem ? Can you sugest me, what must I do to characterize this compound if I can't find the solvent ?
    Pliz, help me ! I almost crazy because of this problem.
    Thank you.
     
  2. jcsd
  3. Mar 15, 2009 #2

    chemisttree

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    What do you intend to do with the solubilized compound? Column chromatography? NMR? MS? what is the counterion? Chloride? If so, try exchanging the counterion with PF6-(using AgPF6) or tetraphenylborate...
     
  4. Mar 15, 2009 #3
    I want to analyze my compound with NMR and MS. But because it can't soluble well at NMR solvent, I worry that I can't characterize this compound. The counterion is I-. Sorry I'm confuse why you suggest me to exchange the counter ion with PF6 or tetraphenylborate ?
    Thank you
     
  5. Mar 15, 2009 #4
    I'll describe what kind of organic synthesis I have done. First, I reacted alcohol (doecyl)with compound which has 2 carboxylic group and 2 ion carboxylic group.Then, I made quartenary amine attached to this compound. So, according to my prediction, this compound has been made well. Can you help me to solve the problem which I get ?
    Pliz, I'll be very grateful if you help me
    thank you
     
  6. Mar 16, 2009 #5
    Pliz,help me !
     
  7. Mar 16, 2009 #6

    chemisttree

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    You are telling me that you couldn't solubilize a quat with TWO dodecyl groups? Sounds fishy. That should be soluble in DCM or DMSO. The iodide salt should be pretty soluble as well. Are you sure you aren't chasing some inorganic material?
     
  8. Mar 17, 2009 #7

    chemisttree

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    BTW, exchanging the counterion with PF6- or tetraphenyl borate will increase the solubility in organic solutions.
     
  9. Mar 19, 2009 #8
    What kind of inorganic material do you mean ? From what process I can get inorganic material ?
    do you know other solvent which is suitable for my compound ?
    Thanks you
     
  10. Mar 19, 2009 #9

    chemisttree

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    How did you make your material? Did you make a lot of material or a little? Have you tried dissolving it in a little D2O with a tiny drop of DCl or D2SO4? Amino acids can have limited solubilities near their isoelectric point and you certainly could have that however unlikely that might seem.

    I once dried a solution with a brine extraction followed by Na2SO4 and managed to isolate a bit of NaCL. It took a while for me to realize what I had done. It didn't dissolve in anything but water as well.
     
  11. Mar 27, 2009 #10

    GCT

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    Could you list the organic solvents that you've employed?
     
  12. Mar 30, 2009 #11
    Water, DMSO, DMAc, DMF, acetic acid, acetone, chloroform, ethyl acetat, dichloromethane, toluene, CCl4, n-hexane
    toluene:DMAc:methanol (2:1:1), acetone:chloroform:dichloromethane:methanol=1:2:1:1,chloroform : THF=1:9, chloromethane:dichloromethane:THF = 2:1:1, chloroform:methanol:THF = 1:1:1, chloroform:methanol:DMAc = 4:2:1 or 7:2:1, chloroform:THF = 9:1 and 1:1, toluene:chloroform = 1:4 and 4:1, n-hexano:toluene:1:1,acetic acid:water = 1:1
    I also try to dissolve my compound with sonic, but it doen't well.
    Can you help me to explain my phenomena ?
    thanks you
     
  13. Mar 31, 2009 #12

    chemisttree

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    You will have to share the details of the synthesis for us to be of any further help.
    You might have made a polymer (unlikely) or you might be chasing an inorganic material.

    Try to burn it. If it is an organic compound then you won't have any residue.
     
  14. Mar 31, 2009 #13
    My route synthesis : My initial compound (it has been purified) has 2 group of carbocylic acid, 2 group of carbocyclic ion (COO-Na+). All of this group is connected with 1 tertiary amine. the tertiary amine is connected with methylene group. Then, I try to react my initial compound with dodecyl alcohol. I assume that all of my carbocylic acid would be esterified. So, I will have 2 long chain ester and 2 chain of carbocylic acid. Next, I react my compound with methylating group, so all of the tertiaty amine would be changed into quartenary amine. Finally, I have 2 quartenary amine(connected wih methylene group), 2 dodecyl group ester and 2 carbocylic ion.
    I want to characterize my compound with NMR. Howevwe, I get problem. Because I don't find the solvent which can dissolve my compound well. I have tried solvent (all of them has been mentioned above), but none of them is suitable to dissolve my compound.
    Does my explanation confuse ?
    Help me, please

    thanks you.
     
  15. Mar 31, 2009 #14
    I have waashed my compound with water, so maybe I assume that I dont't have inorganic material in my system.
    thank you.
     
  16. Apr 1, 2009 #15

    chemisttree

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    Did you do a DCC/DMAP coupling? Could you be playing with the urea?
     
  17. Apr 1, 2009 #16
    No, I didn't DCC/DMAP coupling. I didnt't play with urea. I just did esterification reaction (so I have 2 long ester chain) and, then reacted with methylating agent (so I get 2 quartenary amine). I think, my compound will be zwitter ionic ( 2 quartenary amine and 2 ion carboclic, with 2 long hydrophobic chain ester).
     
  18. Apr 2, 2009 #17

    chemisttree

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    how did you make the ester?
     
  19. Apr 3, 2009 #18
    With reaction dodecyl alcohol (catalyst : SOCl2), reflux method. To characterize it, I did FTIR.
     
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