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Updated: Jun 21, 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
A new route to acyclic diaminocarbenes via lithium-halogen exchange
David R Snead1, Ion Ghiviriga, Khalil A Abboud
1Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, Florida 32611-7200, USA.
Abstract:
A lithium-halogen exchange route has been developed to generate acyclic diaminocarbenes (ADC) from chloroamidinium salts. Convenient access to various ADC complexes (B, Rh, Ir, Pd) stems from a one-pot transmetalation protocol. Formation of a carbenoid species is suggested by 1D and 2D NMR studies with a (13)C-labeled chloroamidinium precursor and also by X-ray structures of transition metal-carbene complexes. Rh-ADC complex 4 is an effective catalyst for the 1,2-addition of aryl boronic acids to aryl aldehydes.
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