Diastereoselective Henry Reaction Catalyzed by Guanidine-Thiourea Bifunctional Organocatalyst

Yoshihiro Sohtome; Nobuko Takemura; Toshitsugu Iguchi; Yuichi Hashimoto; Kazuo Nagasawa

doi:10.1055/s-2005-922770

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Diastereoselective Henry Reaction Catalyzed by Guanidine-Thiourea Bifunctional Organocatalyst

Yoshihiro Sohtome^a, Nobuko Takemura^b, Toshitsugu Iguchi^b, Yuichi Hashimoto^a, Kazuo Nagasawa*^b
^a Institute of Molecular and Cellular Biosciences, The University of Tokyo Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
^b Department of Biotechnology and Life Science, Faculty of Technology, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan
Fax: +81(42)3887295; e-Mail: knaga@cc.tuat.ac.jp;

Abstract

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Abstract

A highly diastereoselective Henry reaction (diastereomer ratio of 84:16 to 99:1) of α-substituted aldehydes with nitromethane was developed using guanidine-thiourea bifunctional catalyst 1. N,N-Dibenzyl-protected α-amino aldehydes (2a, 2d-h) and α-hydroxy aldehydes protected as silyl ethers (2i-j) were suitable substrates. The matched combination of this catalytic system, i.e., S-aldehydes and (R,R)-1 catalyst, can be understood in terms of the transition state of the asymmetric version of the Henry reaction catalyzed by 1.

Key words

bifunctional organocatalyst - guanidine - thiourea - Henry reaction - diastereoselective reaction

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References

References and Notes

1 Henry LCR. Hebd. Séances Acad. Sci. 1895, 120: 1265

For recent reviews, see:

2a Palomo C. Oiarbide M. Mielgo A. Angew. Chem. Int. Ed. 2004, 43: 5442

2b Luzio FA. Tetrahedron 2001, 57: 915

2c Ono N. The Nitro Group in Organic Synthesis Wiley-VCH; Weinheim: 2001.

2d Shibasaki M. Gröger H. In Comprehensive Asymmetric Catalysis Vol. 3: Jacobsen EN. Pfaltz A. Yamamoto H. Springer; Berlin: 1999. p.1075

2e Shibasaki M. Gröger H. Kanai M. In Comprehensive Asymmetric Catalysis Suppl. 1: Jacobsen EN. Pfaltz A. Yamamoto H. Springer; Heidelberg: 2004. p.131

Selected examples using TBAF as a base, see:

3a Hanessian S. Devasthale PV. Tetrahedron Lett. 1996, 37: 987

3b Soengas RG. Esteves JC. Esteves RJ. Org. Lett. 2003, 5: 4457

3c Bernardi L. Bonini BF. Dessole G. Fochi M. Comes-Franchini M. Gavioli S. Ricci A. Varchi G. J. Org. Chem. 2003, 68: 1418

3d Looper RE. Williams RM. Angew. Chem. Int. Ed. 2004, 43: 2930

3e Highly diastereoselective Henry reaction under high pressure, see: Misumi Y. Matsumoto K. Angew. Chem. Int. Ed. 2002, 41: 1031

4 Sasai H. Kim W.-S. Suzuki T. Shibasaki M. Misuda M. Hasegawa J. Ohashi T. Tetrahedron Lett. 1994, 35: 6123

5 Corey EJ. Zhang F.-Y. Angew. Chem. Int. Ed. 1999, 38: 1931

6a Chinchilla R. Najera C. Sanchez-Agullo P. Tetrahedron: Asymmetry 1994, 5: 1393

6b Allingham MT. Howard-Jones A. Murphy PJ. Thomas DA. Caulkett PWR. Tetrahedron Lett. 2003, 44: 8677

6c Nagasawa K. Georgieva A. Takahashi H. Nakata T. Tetrahedron 2000, 56: 187

6d Nagasawa K. Georgieva A. Takahashi H. Nakata T. Tetrahedron 2001, 57: 8959

6e Kita T. Georgieva A. Hashimoto Y. Nakata T. Nagasawa K. Angew. Chem. Int. Ed. 2002, 41: 2832

6f Sohtome Y. Hashimoto Y. Nagasawa K. Adv. Synth. Catal. 2005, 347: 1643

6g Ishikawa T. Isobe T. Chem.-Eur. J. 2002, 8: 553

6h Corey EJ. Grogan MJ. Org. Lett. 1999, 1: 157

6i Ma D. Pan Q. Han F. Tetrahedron Lett. 2002, 43: 9401

7 Reetz MT. Chem. Rev. 1999, 99: 1121

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Diastereoselective Henry Reaction of 2a with Nitromethane in the Presence of ( R , R )-1.
To a mixture of (R,R)-1 (8.4 mg, 0.0073 mmol), KI (6.0 mg, 0.037 mmol), 2a (24.0 mg, 0.073 mmol) and nitromethane (392 µL, 0.73 mmol) in toluene (0.7 mL) was added 8 mM aq KOH (0.7 mL) at 0 °C. The resulting mixture was stirred vigorously at 0 °C for 24 h. Then, sat. aq NH₄Cl was added, and the organic layer was extracted with EtOAc. The extracts were dried over MgSO₄, filtered and concentrated in vacuo, and the residue was purified by column chromatography on silica gel (hexane-EtOAc = 20:1, 10:1, 5:1, 1:0) to give 3a (21.1 mg, 75%) and (R,R)-1 (8.3 mg, 99% recovery). The relative stereochemistry and diastereoselectivity of 3a (95:5) were determined based on the ¹H NMR spectra reported by Corey et al. [5] The enantiomeric excess of 3a (99% ee) was determined by means of chiral HPLC analysis. [CHIRALCEL OJ-H, 0.46 cm (∅) × 25 cm (L), n-hexane-ethanol = 90:10, 1.0 mL/min, minor: 28.8 min, major: 31.3 min].

9a Boyle PH. Convery MA. Davis AP. Hosken GD. Murray BA. J. Chem. Soc., Chem. Commun. 1992, 239

9b van Haken E. Wynberg H. van Bolhuis F. J. Chem. Soc., Chem. Commun. 1992, 629

9c Schmidtchen FP. Berger M. Chem. Rev. 1997, 97: 1609

Reviews, see:

10a Schreiner PR. Chem. Soc. Rev. 2003, 32: 289

10b Pihko PM. Angew. Chem. Int. Ed. 2004, 43: 2062

10c Asymmetric reaction using Jacobsen’s catalyst, see: Fuerst DE. Jacobsen EN. J. Am. Chem. Soc. 2005, 127: 8964 ; and references therein

10d Takemoto’s bifunctional catalyst, see: Hoashi Y. Okino T. Takemoto Y. Angew. Chem. Int. Ed. 2005, 44: 807 ; and references therein

10e Bis-thiourea-type catalyst, see: Sohtome Y. Tanatani A. Hashimoto Y. Nagasawa K. Tetrahedron Lett. 2004, 45: 5589

Other catalysts, see:

10f Sohtome Y. Tanatani A. Hashimoto Y. Nagasawa K. Chem. Pharm. Bull. 2004, 52: 477

10g Vakulya B. Varga S. Csampai A. Soos T. Org. Lett. 2005, 7: 1967

11

The stereochemistry of 3i was determined from the NOE of 5i. The stereochemistry of 3j was determined by comparison of the ¹H NMR spectrum with that of 3i (Scheme [1] ).