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Cobalt‐Catalyzed ortho ‐Methylation of Ferrocenes Bearing ortho ‐Directing Groups by Catalytic Directed C–H Bond Activation
Author(s) -
Schmiel David,
Butenschön Holger
Publication year - 2017
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201700358
Subject(s) - chemistry , catalysis , cobalt , ferrocene , yield (engineering) , transition metal , medicinal chemistry , methylation , surface modification , metal , combinatorial chemistry , organic chemistry , gene , biochemistry , materials science , electrode , metallurgy , electrochemistry
Transition‐metal‐catalyzed C–H functionalization is an emerging powerful alternative to ortho ‐lithiation protocols. For ferrocene systems almost exclusively noble‐metal catalysts have so far been used. Herein we present the first examples of cobalt‐catalyzed ortho ‐methylations by C–H activation at ferrocenes bearing various ortho ‐directing groups (ODGs). The cobalt‐catalyzed ortho ‐methylation results in the formation of racemic 1,2‐disubstituted ferrocenes in 21–89 % yield. In some cases symmetric 2,5‐dimethylated ferrocenes prevailed or even were the only isolated products.