Rh(I)-catalyzed CO gas-free carbonylative cyclization reactions of alkynes with 2-bromophenylboronic acids using formaldehyde.
The rhodium(I)-catalyzed reaction of alkynes with 2-bromophenylboronic acids in the presence of paraformaldehyde resulted in a CO gas-free carbonylative cyclization, yielding indenone derivatives. [RhCl(BINAP)](2) and [RhCl(cod)](2) were responsible for the decarbonylation of formaldehyde and the subsequent carbonylation of alkynes with 2-haloboronic acids, respectively, leading to efficient whole carbonylation. Sterically bulky and electron-withdrawing groups on unsymmetrically substituted alkynes favored the alpha-position of indenones.
Morimoto
Tsumoru
T
Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), Takayama, Ikoma, Nara 630-0192, Japan.
Yamasaki
Kae
K
Hirano
Akihisa
A
Tsutsumi
Ken
K
Kagawa
Natsuko
N
Kakiuchi
Kiyomi
K
Harada
Yasuyuki
Y
Fukumoto
Yoshiya
Y
Chatani
Naoto
N
Nishioka
Takanori
T