Synthesis of benzo-fused lactams and lactones via Ru(II)-catalyzed cycloaddition of amide- and ester-tethered alpha,omega-diynes with terminal alkynes: electronic directing effect of internal conjugated carbonyl group.
In the presence of a catalytic amount of Cp*RuCl(cod), 1,6- and 1,7-diynes connected by an amide or an ester tether underwent cycloaddition with terminal alkynes at room temperature to give rise to cycloadducts in 40-93% yields with 63 : 37-83 : 17 regioisomer ratios.
Yamamoto
Yoshihiko
Y
Department of Applied Chemistry, Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan. yamamoto@apchem.nagoya-u.ac.jp
Kinpara
Keisuke
K
Saigoku
Tomoaki
T
Nishiyama
Hisao
H
Itoh
Kenji
K