No abstract

The previously reported Fe-catalyzed ortho C− H arylation of benzamides relied on bi-or tridentate amide groups and specific iron ligands and was sensitive to steric hindrance. By using new mixed titanates, our present protocol accommodates various weakly coordinating benzamides and tolerates high steric hindrance and sensitive functional groups only under the catalysis of FeCl 3 and TMEDA. A wide range of privileged condensed ring compounds can thus be facilely accessed.

Regioselective difunctionalization of arenes remains a long-standing challenge in organic chemistry. We report a novel and general Fe/Ti synergistic methodology for regioselective synthesis of various polysubstituted arenes through either E/E′ or Nu/E ortho difunctionalizations of arenes. Preliminary results showed that an unprecedented 1,2-Fe/Ti heterobimetallic arylene intermediate bearing two distinct C–M bonds is essential to the regioselective difunctionalization.

Iron-catalyzed stereospecific arylation of enol tosylates with Grignard reagents.

The combination of commonly used FeCl3/SIPr with Ti­(OEt)4/PhOM enabled a highly general iron-based catalyst system, which could efficiently catalyze the biaryl coupling reaction between various electrophiles (I, Br, Cl, OTs, OCONMe2, OSO2NMe2) and common or functionalized aryl Grignard reagents with high functional group tolerance. Selective couplings of aryl iodides and bromides over the corresponding oxygen-based electrophiles have been achieved, and thus a terphenyl acid intermediate for anidulafungin was conveniently synthesized via an orthogonal coupling strategy.