Researchers at the University of Milano Bicocca optimized a protocol for the synthesis of different classes of both molecular and polymeric organic semiconductors enabling the use of water as the sole solvent. Reactions are efficient and do not require heating or atmosphere control. The process is based on the use of a commercially available surfactant (Kolliphor EL) enabling the formation of micelles not easily permeated by oxygen. Such association colloids provide nanoreactors where water insoluble materials can accumulate and react, eventually to be expelled in the water phase directly in the crystalline form.
Examples of semiconductors accessible through such route include diketopyrrolopyrroles (used in OPV), perylene and naphthalenediimides (osed in OFET) and polyfluorenes (relevant for OLEDs). The research unit is now extending the protocol to the preparation of thermosensitive materials pertaining to the class of the latent pigments.
Reference: Mattiello, S. et al., 2017. Suzuki–Miyaura Micellar Cross-Coupling in Water, at Room Temperature, and under Aerobic Atmosphere. Organic Letters, 19(3), pp.654–657.