3484
E. Boyd et al. / Tetrahedron Letters 46 (2005) 3479–3484
(1H, d, J 14.6 Hz, CHCHDPh), 2.79 (1H, br m, NCH),
2.47 (1H, br m, NCH), 1.73 (4H, br m, 4 · CH) and
1.21 (4H, br m, 4 · CH); dC (100 MHz, CDCl3): 129.8,
129.0, 128.5, 128.2, 127.8, 127.5, 127.0 and 126.3
(8 · CH; 3 · Ph) 85.7 (NCN), 68.6 (NCH2Ph), 67.5
(NCH2Ph), 56.4 (NCH), 52.3 (NCH), 30.5 (CH2), 29.9
(CH2) and 24.5 (2 · CH2).
EPSRC National Mass Spectrometry Service (Swansea)
for mass determinations.
References and notes
1. (a) Costa, A. M.; Jimeno, C.; Gavenonis, J.; Carroll, P. J.;
Walsh, P. J. J. Am. Chem. Soc. 2002, 124, 6929; (b)
Annunziata, R.; Benaglia, M.; Caporale, M.; Raimondi, L.
Tetrahedron: Asymmetry 2002, 13, 2727; (c) Vasse, J.-L.;
Stranne, R.; Zalubovskis, R.; Gayet, C.; Moberg, C. J. Org.
Chem. 2003, 68, 3258; (d) Johansson, M. J.; Schwartz, L.;
Amedjkouh, M.; Kann, N. Tetrahedron: Asymmetry, 2004, 15,
3531.
2. (a) Kizirian, J.-C.; Caille, J.-C.; Alexakis, A. Tetrahedron
Lett. 2003, 44, 8893; (b) Cobb, A. J. A.; Marson, C. M.
Tetrahedron: Asymmetry 2001, 12, 1547.
3. Padmaja, M.; Periasamy, M. Tetrahedron: Asymmetry
2004, 15, 2437.
4. For a related example see Ref. 5.
5. Alexakis, A.; Andrey, O. Org. Lett. 2002, 4, 3611.
6. Arjan, H.; Boyd, E.; Coumbarides, G. S.; Eames, J.;
Jones, R. V. H.; Stenson, R. A.; Suggate, M. J. Tetra-
hedron Lett. 2005, 46, 1921.
7. Boyd, E.; Coumbarides, G. S.; Eames, J.; Jones, R. V. H.;
Motevalli, M.; Stenson, R. A.; Suggate, M. J. Tetrahedron
Lett. 2005, 46, preceding communication see: doi:10.1016/
j.tetlet.2005.03.128.
8. (a) Alexakis, A.; Mutti, S.; Normant, J. F. Tetrahedron
Lett. 1988, 29, 4411; (b) Alexakis, A.; Mangeney, P.;
Marek, I.; Rose-Munch, F.; Rose, E.; Semra, A.; Robert,
F. J. Am. Chem. Soc. 1992, 114, 8288.
9. Denmark, S. E.; Stadler, H.; Dorow, R. L.; Kim, J.-H.
J. Org. Chem. 1991, 56, 5063.
2.2. (À)-(R,R)-N,N,N0-Tribenzyl-1,2-diaminocyclo-
hexane 15
Sodium borohydride (2.27 g, 60.6 mmol) was cautiously
added to a solution of aminal (R,R)-14 (4.64 g,
12.1 mmol) in ethanol (50 mL). The resulting solution
was stirred for 1 h at room temperature and reflux for
a further 12 h. The solvent was removed under vacuum.
The residue was dissolved in dichloromethane (20 mL).
Dilute aqueous HCl (1 M, 3 mL) was added dropwise
until the effervescence ceased. The organic layer was
separated, dried over MgSO4 and evaporated under
reduced pressure to give (À)-(R,R)-N,N,N0-tribenzyl-
1,2-diaminocyclohexane 15 (3.67 g, 79%) as a yellow
22
oil; ½aꢀ À46.2 (c 2.9, CHCl3); mmax (NaCl)/cmÀ1
D
3301 (N–H), 2804, 1604, 1496, 1454, 1311 and 1026;
dH (270 MHz, CDCl3): 7.22–7.15 (15H, m, 15 · CH;
3 · Ph), 3.87 (1H, d, J 13.9 Hz, CHAHBPh), 3.74 (2H,
d, J 13.7 Hz, 2 · CHAHBPh), 3.51 (1H, d, J 13.9 Hz,
CHAHBPh), 3.40 (2H, d, J 13.7 Hz, 2 · CHAHBPh),
2.49 (2H, br m, 2 · NCH), 2.12 (1H, m, CH), 2.01
(1H, m, CH), 1.80 (2H, m, 2 · CH), 1.67 (1H, br s,
NH) and 1.20 (4H, br m, 4 · CH); dC (67.5 MHz,
CDCl3): 141.0, 140.0, 130.0, 129.1, 128.8, 128.4, 128.2,
127.8, 127.6, 127.4, 126.9 and 126.6 (12 · C; 3 · Ph),
62.1 (CN), 57.9 (CN), 53.8 (CN), 53.6 (CN), 51.5
(CN), 31.8, 25.8, 24.7 and 22.8 (4 · CH2).
10. Brunel, J.-M.; Villard, R.; Buono, G. Tetrahedron Lett.
1999, 40, 4669.
11. Review: Bennani, Y. I.; Hanessian, S. Chem. Rev. 1997,
97, 3161; For a recent example, see: OꢀBrien, P.; Pilgram,
C. D. Org. Biomol. Chem. 2003, 1, 523.
12. Review: (a) Lucet, D.; Le Gall, T.; Mioskowski, C. Angew.
Chem., Int. Ed. 1998, 37, 2580; For some examples, see: (a)
Corey, E. J.; Sarshar, S.; Azimioara, M. D.; Newbold, R. C.;
Noe, M. C. J. Am. Chem. Soc. 1996, 118, 7851; (b)
Kobayashi, S.; Horibe, M. J. Am. Chem. Soc. 1994, 116,
9805.
Acknowledgements
We are grateful to The Royal Society, The University of
London Central Research Fund and Syngenta (Grange-
mouth, Scotland) for their financial support, and the