Enantioselective Catalysis; 150: [1] Chiral-at-Metal (η⁶-p-Cymene)Ruthe­nium(II) Complexes of Binaphthyl Ligands - Synthesis, Characterization, and Enantioselective Catalysis

Abstract

Neutral and cationic half-sandwich (η⁶-p-cymene)ruthenium complexes 9-12 with chiral Schiff base ligands derived from binaphthylamino derivatives and salicylaldehyde, diphenyl(2-formylphenyl)phosphane, and 2-pyridinealdehyde form two dia­stereomers which only differ in the metal configuration. From the diastereomeric mixtures of compounds 10 and 12 the major dia­stereomers crystallize, whereas for compound 9 both diastereomers co-crystallize in a 1:1 ratio in the same single crystal. In compounds 13 and 14 containing the reduced Schiff base ligands, the nitrogen atom of the secondary amine functionality becomes another chiral center. In solution at room temperature the various diastereomers interconvert rapidly. The new compounds were used as catalysts in the enantioselective transfer hydrogenation of acetophenone with 2-propanol and in the Diels-Alder reaction of cyclopentadiene with methacrolein.

Key words

enantioselectivity - catalysis - ruthenium half-sandwich complexes - 1,1′-binaphthyl ligands - chiral imines

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Part 149: Brunner, H.; Zettler, C.; Zabel, M. Chem. Monthly in press.

References

• 3 Naota T. Takaya H. Murahashi S.-I. Chem. Rev.  1998,  98:  2599 
• 4 Noyori S. Hashiguchi S. Acc. Chem. Res.  1997,  30:  97 
• 5 Brunner H. Nuber B. Prommesberger M. Tetrahedron: Asymmetry  1998,  9:  3223 
• 6 Brunner H. Zettlmeier W. Handbook of Enantioselective Catalysis with Transition Metal Compounds   VCH; Weinheim: 1993. 
• 7 Budzelaar PHM. Moonen NNP. de Gelder R. Smits JMM. Gal AW. Eur. J. Inorg. Chem.  2000,  753 
• 8 Willems STH. Budzelaar PHM. Moonen NNP. de Gelder R. Smits JMM. Gal AW. Chem.-Eur. J.  2002,  1310 
• 9 Miyano S. Okada S. Hotta H. Takeda M. Kabuto C. Hashimoto H. Bull. Chem. Soc. Jpn.  1989,  62:  1528 
• 10 Hattori T. Shijo M. Sakamoto J. Kumagai S. Nakajima A. Miyano S. J. Chem. Res., Miniprint  1995,  124 
• 11 Ding K. Wang Y. Yun H. Liu J. Wu Y. Terada M. Okubo Y. Mikami K. Chem.-Eur. J.  1999,  5:  1734 
• 12 VyskoËil S. mrËina M. Lorenc M. Hanu V. Poláek M. KoËovsk˝ P. Chem. Commun.  1998,  585 
• 13 Brunner H. Henning F. Weber M. Tetrahedron: Asymmetry  2002,  13:  37 
• 14 Zhou X.-G. Huang J.-S. Ko P.-H. Cheung K.-K. Che C.-M. J. Chem. Soc., Dalton Trans.  1999,  3303 
• 15 Carreira EM. Singer RA. Lee W. J. Am. Chem. Soc.  1994,  116:  8837 
• 16 Weber M. Ph.D. Thesis   University of Regensburg; Germany: 2002. 
• 19 Lecomte C. Dusausoy Y. Protas J. Tirouflet J. Dormond A. J. Organomet. Chem.  1974,  73:  67 
• 20 Brunner H. Enantiomer  1997,  2:  133 
• 21 Cahn RS. Ingold CK. Prelog V. Angew. Chem., Int. Ed. Engl.  1966,  5:  413 ; Angew. Chem. 1966, 78, 413
• 22 Carmona D. Vega C. Lahoz FJ. Elipe S. Oro LA. Lamata MP. Viguri F. García-Correas R. Cativiela C. López-Ram de Víu MP. Organometallics  1999,  18:  3364 
• 23 Evans DA. Murry JA. von Matt P. Norcross RD. Miller SJ. Angew. Chem., Int. Ed. Engl.  1995,  34:  798 ; Angew. Chem. 1995, 107, 863
• 24 Bennett MA. Huang T.-N. Matheson TW. Smith AK. Inorg. Synth.  1982,  21:  74 

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Part 149: Brunner, H.; Zettler, C.; Zabel, M. Chem. Monthly in press.

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X-ray structure analyses.

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Brunner, H.; Weber, M.; Zabel, M.; Zwack, T. Angew. Chem. Int. Ed., in press.

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Brunner, H.; Weber, M.; Zabel, M. Coord. Chem. Rev. in press.

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Crystallographic data (excluding structure factors) for the structures in this paper have been deposited with the Cambridge Crystallographic Data Centre. Copies of the data can be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge CB2, UK [fax:[phone] or e-mail: [e-mail]].