title: A highly efficient and selective aerobic cross-dehydrogenative-coupling reaction photocatalyzed by a platinum(II) terpyridyl complex.
abstract: Thanks to the superior redox potential of platinum(II) complex compared with that of Ru(bpy)3(2+) in the excited state, an efficient and selective visible-light-induced CDC reaction has been developed by using a catalytic amount (0.25 %) of 1. With the aid of FeSO4 (2 equiv), the corresponding amide could not be detected under visible-light irradiation (λ=450 nm), but the desired cross-coupling product was exclusively obtained under ambient air conditions. A spectroscopic study and product analysis revealed that the CDC reaction is initiated by photoinduced electron-transfer from N-phenyltetrahydroisoquinoline to the complex. An EPR (electron paramagnetic resonance) experiment provides direct evidence on the generation of superoxide radical anion (O2(-·)) rather than singlet oxygen ((1)O2) under irradiation of the reaction system, in contrast to that reported in the literature. Combined, the photoinduced electron-transfer and subsequent formation of superoxide radical anion (O2(-·)) results in a clean and facile transformation.
authors.affiliation: Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, PR China.
authors.forename: Jian-Ji
authors.initials: JJ
authors.lastname: Zhong
authors.forename: Qing-Yuan
authors.initials: QY
authors.lastname: Meng
authors.forename: Ge-Xia
authors.initials: GX
authors.lastname: Wang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Ke
authors.initials: K
authors.lastname: Feng
authors.forename: Chen-Ho
authors.initials: CH
authors.lastname: Tung
authors.forename: Li-Zhu
authors.initials: LZ
authors.lastname: Wu