| 19788301 |
Yanagisawa S, Ueda K, Sekizawa H, Itami K: Programmed synthesis of tetraarylthiophenes through sequential C-H arylation. J Am Chem Soc. 2009 Oct 21;131(41):14622-3.
A general protocol for the programmed synthesis of tetraarylthiophenes has been established. The utilization of three catalysts, RhCl (CO){P [OCH (CF (3))(2)](3)}(2), PdCl (2)/P [OCH (CF (3))(2)](3), and PdCl (2)/bipy, enables regioselective sequential arylations at the three C-H bonds of 3-methoxythiophene with iodoarenes. Interesting metal- and ligand-controlled regiodivergent C-H arylations have been uncovered during this study. The installation of fourth aryl groups to the thus-generated 2,4,5-triaryl-3-methoxythiophenes has been accomplished through a sequence of demethylation, triflation, and Suzuki-Miyaura coupling. |
6(0,0,1,1) |