TY - JOUR
T1 - The central role of the metal ion for photoactivity
T2 - Zn-vs.Ni-Mabiq
AU - Lauenstein, Raphael
AU - Mader, Sophie L.
AU - Derondeau, Henrieta
AU - Esezobor, Oaikhena Z.
AU - Block, Matthias
AU - Römer, Armin J.
AU - Jandl, Christian
AU - Riedle, Eberhard
AU - Kaila, Ville R.I.
AU - Hauer, Jürgen
AU - Thyrhaug, Erling
AU - Hess, Corinna R.
N1 - Publisher Copyright:
© The Royal Society of Chemistry 2021.
PY - 2021/6/7
Y1 - 2021/6/7
N2 - Photoredox catalysts are integral components of artificial photosystems, and have recently emerged as powerful tools for catalysing numerous organic reactions. However, the development of inexpensive and efficient earth-abundant photoredox catalysts remains a challenge. We here present the photochemical and photophysical properties of a Ni-Mabiq catalyst ([NiII(Mabiq)]OTf (1); Mabiq = 2-4:6-8-bis(3,3,4,4-tetramethyldihydropyrrolo)-10-15-(2,2-biquinazolino)-[15]-1,3,5,8,10,14-hexaene1,3,7,9,11,14-N6)—and of a Zn-containing analogue ([ZnII(Mabiq)OTf] (2))—using steady state and time resolved optical spectroscopy, time-dependent density functional theory (TDDFT) calculations, and reactivity studies. The Ni and Zn complexes exhibit similar absorption spectra, but markedly different photochemical properties. These differences arise because the excited states of2are ligand-localized, whereas metal-centered states account for the photoactivity of1. The distinct properties of the Ni and Zn complexes are manifest in their behavior in the photo-driven aza-Henry reaction and oxidative coupling of methoxybenzylamine.
AB - Photoredox catalysts are integral components of artificial photosystems, and have recently emerged as powerful tools for catalysing numerous organic reactions. However, the development of inexpensive and efficient earth-abundant photoredox catalysts remains a challenge. We here present the photochemical and photophysical properties of a Ni-Mabiq catalyst ([NiII(Mabiq)]OTf (1); Mabiq = 2-4:6-8-bis(3,3,4,4-tetramethyldihydropyrrolo)-10-15-(2,2-biquinazolino)-[15]-1,3,5,8,10,14-hexaene1,3,7,9,11,14-N6)—and of a Zn-containing analogue ([ZnII(Mabiq)OTf] (2))—using steady state and time resolved optical spectroscopy, time-dependent density functional theory (TDDFT) calculations, and reactivity studies. The Ni and Zn complexes exhibit similar absorption spectra, but markedly different photochemical properties. These differences arise because the excited states of2are ligand-localized, whereas metal-centered states account for the photoactivity of1. The distinct properties of the Ni and Zn complexes are manifest in their behavior in the photo-driven aza-Henry reaction and oxidative coupling of methoxybenzylamine.
UR - http://www.scopus.com/inward/record.url?scp=85107266169&partnerID=8YFLogxK
U2 - 10.1039/d0sc06096h
DO - 10.1039/d0sc06096h
M3 - Article
AN - SCOPUS:85107266169
SN - 2041-6520
VL - 12
SP - 7521
EP - 7532
JO - Chemical Science
JF - Chemical Science
IS - 21
ER -