Ruthenium-catalyzed cyclotrimerization of alkynylboronates and iodoalkynes

ORGN 613

Yoshihiko Yamamoto, yamamoto@apchem.nagoya-u.ac.jp, Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya, 464-8603, Japan
Syntheses of polysubstituted benzenes have often encountered difficulties in controlling regioselectivity and incompatibility to labile functionalities. Highly substituted benzeneboronic acid esters were synthesized by using ruthenium-catalyzed [2 + 2 + 2] cycloaddition of alkynylboronates under mild conditions. Multiply substituted iodobenzenes were also efficiently synthesized with defined substitution patterns via ruthenium-catalyzed [2 + 2 + 2] cycloaddition of iododiynes.