C-H borylation (CHB) is a method to functionalize C-H bonds. The development of CHB has taken many years but is getting to the point of well-established chemistry. The directed CHB is possible for a variety of differing substrates and differing loctions of direction. A new method for ortho directed CHB of esters amides and ketones was developed through the use of pyridine based monodentate ligands.Using 4-cyano-2-methoxypyridine as a ligand iridium catalyzed CHB of esters ketones and amides were performed. The mechanism of CHB in this process likely operates through a different rate-determining step than the other C-H borylation methods used as it was found that the kinetic isotope effect data did not clearly support C-H activation as rate-determining.The development of sp3 C-H borylation is not as advanced as sp2 CHB; a 2-step process to generate the same products could be equally desirable. Utilizing a borylation-hydrogenation process the selectivity that have already been developed for sp2 C-H borylation can be used to generate the sp3 carbon boron bond at the desired location. This process has been developed and limitations of it have been investigated.
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