Self-indicating resins: Sensor beads and in situ reaction monitoring

Solid-phase organic synthesis and solution-phase parallel synthesis assisted by polymer-supported reagents, or scavenger resins, enable painstaking purifications to be avoided during synthesis. This concept was applied to reaction monitoring through the development of resin-bound indicators for the efficient analysis of various chemistries. Bromophenol blue was chosen as the indicator and attached to the resin after derivatization. The resin was successfully used as a "sensor" for monitoring solid-phase peptide synthesis, and applied for in situ reaction monitoring during the synthesis of a library of ureas in a highly successful manner.