Transition-metal-catalyzed cross-coupling reactions have revolutionized chemical syntheses in recent years. Though much work has been done in this field, challenges in this coupling manner still remain. One is that few examples of oxidative C(sp)-C(sp3) bond formation have been reported. Another problem is that while typical terminal oxidants used in oxidative transformations, direct utilization of the more practical molecular oxygen or air as oxidants remains a continuing challenge

 

Recently, researchers of Wuhan University and Lanzhou Institute of Chemical Physics (LICP), have demonstrated an operationally simple and efficient method for the construction C(sp)-C(sp3) bonds fromterminal alkynes and alkylzinc reagents via Pd-catalyzed oxidative coupling. Air can serve as the sole oxidant in this oxidative coupling reaction, and CO was found to be critical in terms of enhancing the chemical yield and selectivity.

 

To the best of the researchers’ knowledge, this is the first example of Pd-catalyzed aerobic oxidative C(sp)-C(sp3) coupling employing terminal alkynes as one nucleophile and alkylzinc reagents as the other nucleophile.

This work was supported by the National Natural Science Foundation of China and was published in J. AM. CHEM. SOC. (J. AM. CHEM. SOC. 2010, 132, 4101–4103).

Abstract of the paper published in J. AM. CHEM. SOC.