Recently graduated MChem student Luca Dobson, working in the lab of Dr. Graham Pattison, has published the first Rh-catalysed arylation of fluorinated ketones with boronic acids in Chem Comm. Fluorinated molecules are of wide interest in medicinal and materials chemistries and over 30% of all commercial drugs contain a fluorine atom because of the beneficial effect the element can impart on biological activity. This reaction allows a safe and sustainable route for the production of fluorinated tertiary alcohol building blocks using reagents which are air- and moisture-stable.
Interestingly, we showed the difluorinated (CF2H) ketone to be more reactive than the trifluoromethyl (CF3) ketone, despite the fact each additional fluorine atom provides extra electronic activation. We believe this effect to be because of the larger size of the CF3 group compared to the CF2H group hindering key reaction steps at the metal centre.