N-Boc-2-硫代哌啶的高对映选择性催化动态拆分:(R)-(+)-N-Boc-哌啶酸、(S)-(-)-Coniine、(S)-(+)-Pelletierine、 (+)-β-Conhydrine 和 (S)-(-)-罗哌卡因以及 (-)-Lasubine II 和 (+)-Cermizine C 的正式合成
Highly Enantioselective Catalytic Dynamic Resolution of <i>N</i>-Boc-2-lithiopiperidine: Synthesis of (<i>R</i>)-(+)-<i>N-</i>Boc-Pipecolic Acid, (<i>S</i>)-(−)-Coniine, (<i>S</i>)-(+)-Pelletierine, (+)-β-Conhydrine, and (<i>S</i>)-(−)-Ropivacaine and Formal Synthesis of (−)-Lasubine II and (+)-Cermizine C
作者:Timothy K. Beng、Robert E. Gawley
DOI:10.1021/ja105772z
日期:2010.9.8
syntheses of both enantiomers of 2-substituted piperidines using a wide range of electrophiles. The CDR has been applied to the synthesis of (R)- and (S)-pipecolic acid derivatives, (+)-beta-conhydrine, (S)-(+)-pelletierine, and (S)-(-)-ropivacaine and the formal synthesis of (-)-lasubine II and (+)-cermizine C.
Dynamics of Catalytic Resolution of 2-Lithio-<i>N</i>-Boc-piperidine by Ligand Exchange
作者:Timothy K. Beng、William S. Tyree、Trent Parker、Chicheung Su、Paul G. Williard、Robert E. Gawley
DOI:10.1021/ja307796e
日期:2012.10.10
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.
Application of Catalytic Dynamic Resolution of <i>N</i>-Boc-2-lithiopiperidine to the Asymmetric Synthesis of 2-Aryl and 2-Vinyl Piperidines
作者:Timothy K. Beng、Robert E. Gawley
DOI:10.1021/ol102682r
日期:2011.2.4
The highly enantioselective synthesis of 2-aryl- and 2-vinyl-piperidines has been accomplished through a catalytic dynamic resolution (CDR) of N-Boc-2-lithiopiperidine. The method has been applied to the synthesis of both enantiomers of the tobacco alkaloid anabasine.