Radical Fragment Coupling Route to Geminal Bis(boronates).

The radical addition of dithiocarbonates to 1,1-bis(boronyl)-3-butene and related alkenes occurs without complications from fragmentation or hydrogen atom abstraction and delivers a vast array of highly functional geminal bis(boronates). The ability to assemble geminal bis(boronates) bearing polar functional groups not readily obtained through existing methods is particularly noteworthy. This approach also opens up access to geminal bis(boronyl) cyclopropanes and geminal bis(boronyl) tetrahydroquinolines.