title: The barrier to enantiomerization and dynamic resolution of N-Boc-2-lithiopiperidine and the effect of TMEDA.
abstract: The kinetics of enantiomerization and dynamic thermodynamic resolution (DTR) of N-Boc-2-lithiopiperidine have been measured, revealing significant differences in enthalpy and entropy for these processes and a role for the achiral ligand TMEDA; the racemization and the DTR are catalytic and first order in [TMEDA], and this has implications for asymmetric synthesis with chiral organolithiums.
authors.affiliation: Department of Chemistry, University of Sheffield, Sheffield, UKS3 7HF. i.coldham@sheffield.ac.uk
authors.forename: Iain
authors.initials: I
authors.lastname: Coldham
authors.forename: Daniele
authors.initials: D
authors.lastname: Leonori
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Beng
authors.forename: Robert E
authors.initials: RE
authors.lastname: Gawley
mesh_terms: D002384:Catalysis; D005029:Ethylenediamines / Q000737:chemistry*; D007700:Kinetics; D010880:Piperidines / Q000737:chemistry*; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D005029:Ethylenediamines; D010880:Piperidines; C005798:N,N,N',N'-tetramethylethylenediamine; C032727:piperidine
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