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Updated: Mar 13, 2026
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
cis-Conformation of indigo in the coordination complex (indigo-O,O)(Cp*CrIICl)
Dmitri V Konarev1, Salavat S Khasanov2, Aleksey V Kuzmin2
1Institute of Problems of Chemical Physics RAS, Chernogolovka, Moscow Region, 142432, Russia. konarev3@yandex.ru.
Abstract:
The interaction of decamethylchromocene (Cp*2Cr) with indigo in the presence of a Cl- source yields the coordination complex (indigo-O,O)(Cp*CrIICl) (1) in which one Cp* ligand at chromium is substituted by indigo. Indigo adopts an unusual cis-conformation in 1, allowing the coordination of both indigo carbonyl groups to one CrII center. Complex 1 contains CrII with an S = 1 spin state and indigo0. At the same time, calculations show that an excited ionic state is positioned close to the neutral ground state, providing the appearance of intense low-energy NIR bands in the spectrum of 1 at 820 and 1002 nm attributed to metal-to-ligand charge transfer.
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