(542e) Development of a Continuous Stirred-Tank Reactor (CSTR) Platform for Handling Heterogeneous Visible-Light Photoredox Reactions

Authors: 
Nandiwale, K., Massachusetts Institute of Technology
Pomberger, A., Massachusetts Institute of Technology
Mo, Y., Massachusetts Institute of Technology
Jensen, K. F., Massachusetts Institute of Technology
Robinson, R. I., Novartis Institutes for BioMedical Research
Duvadie, R., Novartis
Visible-light photoredox has been demonstrated to be a powerful synthetic methodology to access pharmaceutical related compounds. However, most of the photoredox reactions involve insoluble starting materials or products which makes it challenging to be implemented in a continuous flow reactor. Here we present a new solid-handling platform for heterogeneous photoredox reaction systems in flow, which integrates a newly designed solid-feeding strategy and a continuous stirred-tank reactor (CSTR) cascade. The residence time distribution for single phase and solids was measured to characterize the hydrodynamics of the heterogeneous flow in the CSTR cascade. Silyl radical-mediated metallaphotoredox cross-electrophile coupling reactions was demonstrated with an inorganic base as the insoluble starting material. Multigram synthesis was achieved within 24 hours of stable operation without any human intervention.