Continuous Flow-Enabled Synthesis of Bench-Stable Bicyclo[1.1.1]pentane Trifluoroborate Salts and Their Utilization in Metallaphotoredox Cross-Couplings

Bicyclo­[1.1.1]­pentane motifs have gained increasing popularity in medicinal chemistry as bioisosteres because of their ability to impact key physicochemical properties. However, reports of direct C­(sp2)–C­(sp3) cross-coupling of these fragments to afford biaryl isosteres have been scarce. Herein we describe the development of continuous flow-enabled synthesis of bench-stable bicyclo[1.1.1]­pentane trifluoroborate salts. Furthermore, we demonstrate the use of metallaphotoredox conditions to enable cross-coupling of these building blocks with complex aryl halide substrates.