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  • Ynamide and Azaalleneyl. Acid‐Base Promoted Chelotropic and Spin‐State Rearrangements in a Versatile Heterocumulene [(Ad)NCC( t Bu)] −
Title: Ynamide and Azaalleneyl. Acid‐Base Promoted Chelotropic and Spin‐State Rearrangements in a Versatile Heterocumulene [(Ad)NCC( t Bu)] −
Abstract We introduce the heterocumulene ligand [(Ad)NCC(tBu)]−(Ad=1‐adamantyl (C10H15),tBu=tert‐butyl, (C4H9)), which can adopt two forms, the azaalleneyl and ynamide. This ligand platform can undergo a reversible chelotropic shift using Brønsted acid‐base chemistry, which promotes an unprecedented spin‐state change of the [VIII] ion. These unique scaffolds are prepared via addition of 1‐adamantyl isonitrile (C≡NAd) across the alkylidyne in complexes [(BDI)V≡CtBu(OTf)] (A) (BDI−=ArNC(CH3)CHC(CH3)NAr), Ar=2,6‐iPr2C6H3) and [(dBDI)V≡CtBu(OEt2)] (B) (dBDI2−=ArNC(CH3)CHC(CH2)NAr). ComplexAreacts with C≡NAd, to generate the high‐spin [VIII] complex with a κ1‐N‐ynamide ligand, [(BDI)V{κ1‐N‐(Ad)NCC(tBu)}(OTf)] (1). Conversely,Breacts with C≡NAd to generate a low‐spin [VIII] diamagnetic complex having a chelated κ2‐C,N‐azaalleneyl ligand, [(dBDI)V{κ2‐N,C‐(Ad)NCC(tBu)}] (2). Theoretical studies have been applied to better understand the mechanism of formation of2and the electronic reconfiguration upon structural rearrangement by the alteration of ligand denticity between1and2.  more » « less
Award ID(s):
2154620
PAR ID:
10510538
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
63
Issue:
21
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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