Development of self-indicating resin.
Previously, we have reported the development and application of self-indicating resins (SIR), materials which can indicate presence or absence of amines in the reaction solution by the conspicuous color change of a phenolsulfophthalein type dye immobilized on resin beads [2a]. Although the functionality necessary for attaching the dye to the resins could be readily introduced by the Suzuki-Miyaura coupling during the synthesis of the SIR 1, this approach was only applicable to the dyes containing suitable functionality for the cross-coupling reaction. In this article we describe a new approach of immobilizing the indicating dyes onto the resin support. The dyes suitable for loading onto aminomethyl polystyrene (PS) resin were prepared by Friedel-Crafts reaction of 2-sulfoterephthalic anhydride with a wide range of phenols. Using this new route, the SIR 6c was readily prepared in >100g quantities. Use of the SIR 6c in the synthesis of a 144 member urea library was demonstrated and the SIR successfully indicated the endpoint of the reaction between amines and isocyanates.
Ichihara
Osamu
O
Evotec UK Ltd., 111 Milton Park, Abingdon, Oxfordshire OX14 4RZ, UK. osamu.ichihara@evotec.com
Sampson
David
D
Whittaker
Mark
M
Bradley
Mark
M
Cho
Jin Ku
JK
D007202:Indicators and Reagents / Q000737:chemistry; D015394:Molecular Structure; D019151:Peptide Library; D011137:Polystyrenes / Q000138:chemical synthesis* / Q000737:chemistry; D012117:Resins, Synthetic / Q000138:chemical synthesis* / Q000737:chemistry
D007202:Indicators and Reagents; D019151:Peptide Library; D011137:Polystyrenes; D012117:Resins, Synthetic