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Dynamics of catalytic resolution of 2-lithio-N-Boc-piperidine by ligand exchange.

ABSTRACT: The dynamics of the racemization and catalytic and stoichiometric dynamic resolution of 2-lithio-N-Boc-piperidine (7) have been investigated. The kinetic order in tetramethylethylenediamine (TMEDA) for both racemization and resolution of the title compound and the kinetic orders in two resolving ligands have been determined. The catalytic dynamic resolution is second order in TMEDA and 0.5 and 0.265 order in chiral ligands 8 and 10, respectively. The X-ray crystal structure of ligand 10 shows it to be an octamer. Dynamic NMR studies of the resolution process were carried out. Some of the requirements for a successful catalytic dynamic resolution by ligand exchange have been identified.

SUBMITTER: Beng TK

PROVIDER: S-EPMC3468710 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Dynamics of catalytic resolution of 2-lithio-N-Boc-piperidine by ligand exchange.

Beng Timothy K TK Tyree William S WS Parker Trent T Su Chicheung C Williard Paul G PG Gawley Robert E RE

Journal of the American Chemical Society 20120925 40

The dynamics of the racemization and catalytic and stoichiometric dynamic resolution of 2-lithio-N-Boc-piperidine (7) have been investigated. The kinetic order in tetramethylethylenediamine (TMEDA) for both racemization and resolution of the title compound and the kinetic orders in two resolving ligands have been determined. The catalytic dynamic resolution is second order in TMEDA and 0.5 and 0.265 order in chiral ligands 8 and 10, respectively. The X-ray crystal structure of ligand 10 shows it ...[more]

PMID: 22967289

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