Bulky rhodium diimine complexes for the catalyzed borylation of vinylarenes

Rhodium(I) complexes containing the bulky diimine ligand (2,6-i-Pr2C6H3)DAB (DAB = 1,4-diaza-1,3-butadiene) have been prepared and characterized fully. The zwitterionic complex Rh(η6-catBcat){(2,6-i-Pr2C6H3)DAB} (3) was prepared in high yield by addition of B2cat3 to Rh(acac){(2,6-i-Pr2C6H3)DAB} (2). These rhodium complexes have been examined for their ability to catalyze the borylation of vinylarenes.

We have prepared and characterized fully three novel rhodium complexes containing a bulky diimine ligand to be used as catalysts for the borylation of vinylarenes. Reactions with B2pin2 (pin = 1,2-O2C2Me4) give the corresponding alkenylboronate esters in high yields.Figure optionsDownload as PowerPoint slide