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Title: Intermediates and mechanism in iron-catalyzed C–H methylation with trimethylaluminum
A mechanistic study is performed on the reaction method for iron-catalyzed C–H methylation with AlMe 3 reagent, previously proposed to involve cyclometalated iron( iii ) intermediates and an iron( iii )/( i ) reaction cycle. Detailed spectroscopic studies ( 57 Fe Mössbauer, EPR) during catalysis and in stoichiometric reactions identify iron( ii ) complexes, including cyclometalated iron( ii ) intermediates, as the major iron species formed in situ under catalytic reaction conditions. Reaction studies identify a cyclometalated iron( ii )-methyl species as the key intermediate leading to C–H methylated product upon reaction with oxidant, consistent with a previously proposed iron( ii )/iron( iii )/iron( i ) reaction manifold for C–H arylation.  more » « less
Award ID(s):
1954480
PAR ID:
10317963
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Chemical Communications
Volume:
57
Issue:
95
ISSN:
1359-7345
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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