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In line with my previous question abot PS-TPP, the problem with pre-fabricated PS-TPP is that the polymer bead strongly immobilizes the TPP molecules and dramaticly decreases the yeild of the reaction, I do the Wittig reaction using TPP monomers and the yield is approximately 100% within 24 hours, but with PS-TPP it is 40-50% afte 3days. so I'm thinking about in-situ polymerization of TPP derivatives, in this orde:
1- I will do the reaction using TPP derivatives monomers
2- after completion of the Wittig reaction I should start the polymerization in the presence of the alkene -which is the product of the Wittig reaction-
3- I will seperate the PS-TPP from the alkene by simple filtration or extract it using diffrent solvents
in this way I will get rid of the time-consuming column chromatography and the effect of immobilization of substrate which decreases the yield. so I will be gratefull if you please help me to find a solution for in-situ preparation of TPP derivatives.
Ah... that clears things up a lot, sorry for the confusion. Thank you.
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I think then that your best bet is using a little nylon condensation chemistry then, just because it is a nice, mild slightly basic environment. Again, with a para substitute on one of your phenyl groups (see image). Standard rxn conditions will give you some water but wont touch any of your C=C product. You could lengthen the c chain between the COOH and NH2 if there are stearic problems. Alternately, you could do a di acid on the TPP and add a di amine or do the reverse (If you didn't want one functionality or the other around during the alkene formation). The nice thing here is the good linear chain length that would be possible.
Alternately, another slick way to handle things would be to have a single amine sub off the benzene and then add a COOH terminated dendrimer, hyperbranched polymer, or starburst polymer. This would bind in regular sized clusters which might be really easy to filter. Or even just use a methacrylate that has a bunch of pendant COOH. A good thing about using PMMA as an extractor is that short chain PMMA can be very soluble in water, possibly allowing for a simple solvent transfer to get most of it out.
Similarly you could do an aldol condensation, but that is almost never as clean.
No matter what, you will need at least one para substitution on one of your benzene groups.
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Dr. Jeffery Raymond
Expertise
Materials chemistry. Materials science. Spectroscopy. Polymer science. Physical Chemistry. General Physics. Technical writing. General Applied Mathematics. Nanomaterials. Optoelectronic Behavior. Science Policy.
Experience
Teaching: General Inorganic Chemistry I & II, Organic Chemistry I & II, Physical Chemistry I, Polymeric Materials, General Physics I, Calculus I & II
My prior experience includes the United States Army and three years as a development chemist in industry.
Currently I am the Assistant Director of the Laboratory for Synthetic Biological Interactions. All told, 13 years of experience in research, development and science education.
Organizations
Texas A&M University, American Chemical Society, POLY-ACS, SPIE
Publications
Journal of the American Chemical Society, Nanoletters, Journal of Physical Chemistry C, Journal of Physical Chemistry Letters, Ultramicroscopy Proceedings of SPIE, Proceedings of MRS, Polymer News, Chemical and Engineering News, Nano Letters, Small, Chemistry.org, Angewandte
Education/Credentials
PhD Macromolecular Science and Engineering (Photophysics/Nanomaterials Concentration), MS Materials Science, BS Chemistry and Physics, Graduate Certificate in Science Policy, AAS Chemical Technology, AAS Engineering Technology
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