Synthesis and Application of Chiral Phosphino-Imidazoline Ligands: Ir-Catalyzed Enantioselective Hydrogenation

Organic Letters

Volumn 4, Issue 26, 2002, Pages 4713-4716

  Menges, Frederik ^a   Neuburger, Markus ^a   Pfaltz, Andreas ^a  

^a UNIVERSITY OF BASEL   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0037619743     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol027253c     Document Type: Article

References (17)

1. Helmchen, G.; Pfaltz, A. Acc. Chem. Res. 2000, 33, 336-345.
2. (a) Schnider, P.; Koch, G.; Prétôt, R.; Wang, G.; Bohnen, F. M.; Krüger, C.; Pfaltz, A. Chem. Eur. J. 1997, 3, 887-892.
3. (b) Lightfoot, A.; Schnider, P.; Pfaltz, A. Angew. Chem., Int. Ed. 1998, 37, 2897-2899. Blackmond, D. G.; Lightfoot, A.; Pfaltz, A.; Rosher, T.; Schnider, P.; Zimmermann, N. Chirality 2000, 12, 442-449.
4. (b) Lightfoot, A.; Schnider, P.; Pfaltz, A. Angew. Chem., Int. Ed. 1998, 37, 2897-2899. Blackmond, D. G.; Lightfoot, A.; Pfaltz, A.; Rosher, T.; Schnider, P.; Zimmermann, N. Chirality 2000, 12, 442-449.
5. Cozzi, P. G.; Zimmermann, N.; Hilgraf, R.; Schaffner, S.; Pfaltz, A. Adv. Synth. Catal. 2001, 343, 450-454.
6. (a) Blankenstein, J.; Pfaltz, A. Angew. Chem., Int. Ed. 2001, 40, 4445-4447.
7. (b) Menges, F.; Pfaltz, A. Adv. Synth. Catal. 2002, 344, 40-44.
8. Pfaltz, A.; Blankenstein, J.; Hilgraf, R.; Hörmann, E.; McIntyre, S.; Menges, F.; Schönleber, M.; Smidt, S. P.; Wüstenberg, B.; Zimmermann, N. Adv. Synth. Catal. In press.
9. For related phosphino-oxazolines and carbene-oxazoline ligands, see: (a) Hou, D.-R.; Reibenspies, J. H.; Burgess, K. J. Org. Chem. 2001, 66, 206-215. (b) Hou, D.-R.; Reibenspies, J.; Colacot, T. J.; Burgess, K. Chem. Eur. J. 2001, 7, 5391-5400. (c) Jones, G.; Richards, C. J. Tetrahedron Lett. 2001, 42, 5553-5555. (d) Powell, M. T.; Hou, D.-R.; Perry, M. C.; Cui, X.; Burgess, K. J. Am. Chem. Soc. 2001, 123, 8878-8879.
10. For related phosphino-oxazolines and carbene-oxazoline ligands, see: (a) Hou, D.-R.; Reibenspies, J. H.; Burgess, K. J. Org. Chem. 2001, 66, 206-215. (b) Hou, D.-R.; Reibenspies, J.; Colacot, T. J.; Burgess, K. Chem. Eur. J. 2001, 7, 5391-5400. (c) Jones, G.; Richards, C. J. Tetrahedron Lett. 2001, 42, 5553-5555. (d) Powell, M. T.; Hou, D.-R.; Perry, M. C.; Cui, X.; Burgess, K. J. Am. Chem. Soc. 2001, 123, 8878-8879.
11. For related phosphino-oxazolines and carbene-oxazoline ligands, see: (a) Hou, D.-R.; Reibenspies, J. H.; Burgess, K. J. Org. Chem. 2001, 66, 206-215. (b) Hou, D.-R.; Reibenspies, J.; Colacot, T. J.; Burgess, K. Chem. Eur. J. 2001, 7, 5391-5400. (c) Jones, G.; Richards, C. J. Tetrahedron Lett. 2001, 42, 5553-5555. (d) Powell, M. T.; Hou, D.-R.; Perry, M. C.; Cui, X.; Burgess, K. J. Am. Chem. Soc. 2001, 123, 8878-8879.
12. For related phosphino-oxazolines and carbene-oxazoline ligands, see: (a) Hou, D.-R.; Reibenspies, J. H.; Burgess, K. J. Org. Chem. 2001, 66, 206-215. (b) Hou, D.-R.; Reibenspies, J.; Colacot, T. J.; Burgess, K. Chem. Eur. J. 2001, 7, 5391-5400. (c) Jones, G.; Richards, C. J. Tetrahedron Lett. 2001, 42, 5553-5555. (d) Powell, M. T.; Hou, D.-R.; Perry, M. C.; Cui, X.; Burgess, K. J. Am. Chem. Soc. 2001, 123, 8878-8879.
13. We have found only one publication on imidazoline-phosphine ligands: Bussaca, C. (Boehringer Ingelheim Pharmaceuticals), US Patent Application, US6316620, 2001. Ligands of this type are also under investigation in the laboratory of Dr. Mike Casey, University College Dublin (Casey, M. Personal communication).
14. We have found only one publication on imidazoline-phosphine ligands: Bussaca, C. (Boehringer Ingelheim Pharmaceuticals), US Patent Application, US6316620, 2001. Ligands of this type are also under investigation in the laboratory of Dr. Mike Casey, University College Dublin (Casey, M. Personal communication).
15. Boland, N. A.; Casey, M.; Hynes, S. J.; Matthews, J. W.; Smyth, M. P. J. Org. Chem. 2002, 67, 3919-3922.
16. - gave better results in the refinement. Crystallographic data has been deposited under CCDC 197021. Further details can be found in Supporting Information.
17. Smidt, S. P.; Mukherje, P.; Pfaltz, A.; Neuburger, M. Unpublished results.