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Updated: May 10, 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
Planar chiral iridium complexes with the Δ-TRISPHAT anion: toward the first enantiopure o-quinone methide π-complex
Jamal Moussa1, Lise Marie Chamoreau, Hani Amouri
1Institut Parisien de Chimie Moléculaire, UMR 7201, Université Pierre et Marie Curie-Paris 6, Paris, France.
Abstract:
We describe the resolution of a planar chiral cationic iridium complex [Cp*Ir(η⁵-2-methyl-oxodienyl)][OT f] (2) following the counterion strategy, where anion metathesis by Δ-TRISPHAT generates the two diastereomers (pR, pS)-[Cp*Ir(η⁵-2-methyl-oxodienyl)][Δ-TRISPHAT] (3a, 3a'). Upon fractional crystallization both compounds were separated as confirmed by ¹H nuclear magnetic resonance (NMR) and circular dichroism studies recorded in solution. The latter represents the key-complex precursors for the enantioselective synthesis of metallated o-quinone methide complexes (4a, 4a').
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