Unlocking the Metalation Applications of TMP-powered Fe and Co(II) Bis(amides): Synthesis, Structure and Mechanistic Insights.

DOI
Publisher DOI
PubMed ID
38563772
Abstract
Typified by LiTMP and TMPMgCl.LiCl, (TMP = 2,2,6,6-tetramethylpiperidide), s-block metal amides have found widespread applications in arene deprotonative metalation. On the contrary transition metal amides lack sufficient basicity to activate these substrates. Breaking new ground in this field, here we present the synthesis and full characterisation of earth abundant transition metals M(TMP)2 (M= Fe, Co). Uncovering a new reactivity profile towards fluoroarenes these amide complexes can promote direct M-H exchange processes regioselectively using one or two of their basic amide arms. Remarkably even when using perfluorinated substrate, selective CH-metalation occurs leaving C-F bonds intact. Their kinetic basicity can be boosted by LiCl or (nBu)4NCl additives which enables formation of kinetically activated ate species. Combining spectroscopic and structural studies with DFT calculations, mechanistic insights have been gained on how these low polarity metalation processes take place. M(TMP)2 can also be used to access ferrocene and cobaltocene by direct deprotonation of cyclopentadiene and to undergo efficient CO2 insertion of both amide groups under mild reaction conditions.
Date Issued
2024-06-10
Publication Type
Article
Subject(s)
Subjects
amide cobal fluoroarenes iron metalation
Language(s)
en
Author(s)
Mu, Manting
Gravolg, Lisa
PeƱas Defrutos, Marconi
Meyer, Karsten
Garcia-Melchor, Max
Additional Credits
Journal
Angewandte Chemie. International edition
Publisher
Wiley
ISSN
1521-3773
Access(Rights)
open.access
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