González Javier R, Soderquist John A
Department of Chemistry, University of Puerto Rico , San Juan, Puerto Rico 00931-3346.
Org Lett. 2014 Jul 18;16(14):3840-3. doi: 10.1021/ol501892a. Epub 2014 Jul 8.
The asymmetric allylboration of N-H aldimines with optically pure trans-4-substituted-2-boryl-1,3-dienes 6 is described. These organoboranes 6 serve as near-perfect asymmetric allylborating agents for N-H aldimines for the preparation of anti-1,2-disubstituted-3,4-pentadien-1-amines 11 as essentially single diastereomers in enantiomerically pure form (>98% de, ≥98% ee). Enantiomerically pure cis-2,3-disubstitued piperidines 12 and α,β-disubstituted-β-amino acids 17 are readily prepared through the standard protocols. A novel Ru-catalyzed hydroamination provides trans-4,5-disubstituted-1-pyrrolines 21 from 11.
本文描述了光学纯的反式-4-取代-2-硼基-1,3-二烯6与N-H醛亚胺的不对称烯丙基硼化反应。这些有机硼烷6作为N-H醛亚胺近乎完美的不对称烯丙基硼化试剂，用于制备反式-1,2-二取代-3,4-戊二烯-1-胺11，其基本上为单一非对映异构体，且对映体纯形式（>98%的非对映体过量，≥98%的对映体过量）。通过标准方法可以很容易地制备对映体纯的顺式-2,3-二取代哌啶12和α,β-二取代-β-氨基酸17。一种新型的钌催化氢胺化反应可从11制备反式-4,5-二取代-1-吡咯啉21。
