On the other hand, planar chiral ferrocenes have been extensively utilized as privileged chiral catalyst and ligands in asymmetric catalysis (
Fig. 1) [
3]. Therefore, intensive efforts have been devoted to their asymmetric synthesis, and significant progress has been achieved using transition-metal-catalysts [
4]. Recently, asymmetric C–H bond functionalization [
5] enables the concise synthesis of planar chiral ferrocenes [
6-
18]. The Binap/Pd catalyzed intramolecular cyclization of ferrocenyl (
o-bromo)aryl ketones, independently developed by You group and Gu
et al., enabled the elegant synthesis of planar chiral ferrocenes (
Scheme 1a) [
8a,
8b]. Then, the synthesis of planar chiral quinilinoferrocenes, with moderate enantioselectivity in some cases, was realized with (
R, Sa)-
O-PINAP as the ligand [
8c]. Soon after that, our group reported the asymmetric synthesis of these scaffolds in excellent enantioselectivity with TADDOL-derived phosphoramidite as ligand [
8d]. Stereospecific synthesis of them could also be realized
via a metallocenic radical pathway [
8j]. Planar-chiral lactam-fused ferrocenes, can serve as precursors of useful planar-chiral pyridines. The planar-chiral lactam-fused ferrocenes with the nitrogen atom directly linked with ferrocenyl ring, are more attractive [
16,
17]. Very recently, a wonderful asymmetric oxidative annulation of twofold C–H bonds and alkynes was realized by using chiral Ni-Al bimetallic catalyst, providing such kind of planar-chiral lactam-fused ferrocenes in excellent
ee values (
Scheme 1b) [
18]. Despite the significant achievement, the efficient asymmetric synthesis of the planar-chiral lactam-fused ferrocenes in a catalytic manner is still highly desirable. Inspired by the previous works on Pd(0)-catalyzed enantioselective C–H activation, we report herein the synthesis of planar-chiral isoquinolinone-fused ferrocenes
via Pd(0)-catalyzed C–H functionalization reaction (
Scheme 1c). (
S, S)-Me-BI-DIME, P-chiral monophosphorus ligands developed by Tang group [
19], proved to be critical, delivering the desired products with up 97%
ee.