ORGANIC
LETTERS
2001
Vol. 3, No. 7
1057-1060
Group-Selective Hydroalumination: A
Novel Route to Stereogenic tert-Alcohol
Centers
Ken Ohmori, Takao Suzuki, Kimiko Taya, Daisuke Tanabe, Toshihiro Ohta, and
Keisuke Suzuki*
Department of Chemistry, Tokyo Institute of Technology, and CREST, Japan Science
and Technology Corporation (JST), O-okayama, Meguro-ku, Tokyo 152-8551, Japan
Received February 6, 2001
ABSTRACT
A new group-selective reaction is described, that is, the hydroalumination of bis-alkynyl alcohols armed with an adjacent stereogenic center,
giving stereo-defined tert-alcohols of potential utility in natural product synthesis.
We report herein a new group-selective reaction1 which
provides us access to a class of stereo-defined tert-alcohols,
e.g., 1-3, with potential utility in natural product synthesis.
1-hexynyl groups reacted predominantly, giving, after depro-
tection, the diol 5a in favor of 5b.6
With no obvious rationale available, we undertook a
systematic study on the structure-selectivity relationship,7
Our interest in this topic traces back to a small, unexpected
finding in our previous project shown in eq 1.2 The reaction
of bis-alkynyl alcohol 43 with LiAlH4 4,5 stopped at the mono-
hydroalumination stage, and amazingly, one of the two
(4) For the hydroalumination reaction of propargyl alcohols, see: (a)
Attenburrow, J.; Cameron, A. F. B.; Chapman, J. H.; Evans, R. M.; Hems,
B. A.; Jansen, A. B. A.; Walker, T. J. Chem. Soc. 1952, 1094-1111. (b)
Jorgenson, M. J. Tetrahedron Lett. 1962, 13, 559-562. (c) Corey, E. J.;
Katzenellenbogen, J. A.; Posner, G. A. J. Am. Chem. Soc. 1967, 89, 4245-
4247. (d) Corey, E. J.; Katzenellenbogen, J. A.; Gilman, N. W.; Roman, S.
A.; Erickson, B. W. J. Am. Chem. Soc. 1968, 90, 5618-5620. (e) Corey,
E. J.; Kirst, H. A.; Katzenellenbogen, J. A. J. Am. Chem. Soc. 1970, 92,
6314-6319. (f) Semmelhack, M. F.; Wu, E. S. C. J. Am. Chem. Soc. 1976,
98, 3384-3386. (g) Rollinson, S. W.; Amos, R. A.; Katzenellenbogen, J.
A. J. Am. Chem. Soc. 1981, 103, 4114-4125. (h) Denmark, S. E.; Jones,
T. K. J. Org. Chem. 1982, 47, 4595-4597. For the mechanism of
hydroalumination, see: (i) Franzus, B.; Snyder, E. I. J. Am. Chem. Soc.
1965, 87, 3423-3429. (j) Snyder, E. I. J. Org. Chem. 1967, 32, 3531-
3534. (k) Borden, W. T. J. Am. Chem. Soc. 1970, 92, 4898-4901. (l) Grant,
B.; Djerassi, C. J. Org. Chem. 1974, 39, 968-970. (m) Kakinuma, K.;
Matsuzawa, T.; Eguchi, T. Tetrahedron 1991, 47, 6975-6982.
(1) For selected examples of group-selective reactions, see: (a) Curran,
D. P.; Qi, H.; DeMello, N. C.; Lin, C.-H. J. Am. Chem. Soc. 1994, 116,
8430-8431. (b) Curran, D. P.; Geib, S. J.; Lin, C.-H. Tetrahedron:
Asymmetry 1994, 5, 199-202. (c) Wipf, P.; Kim, Y. Tetrahedron Lett. 1992,
33, 5477-5480. (d) Harada, T.; Wada, I.; Uchimura, J.; Inoue, A.; Tanaka,
S.; Oku, A. Tetrahedron Lett. 1991, 32, 1219-1222 (e) Schreiber, S. L.;
Schreiber, T. S.; Smith, D. B. J. Am. Chem. Soc. 1987, 109, 1525-1529.
(f) Schreiber, S. L.; Wang, Z. J. Am. Chem. Soc. 1985, 107, 5303-5305.
(g) Waldmann, H. Organic Synthesis Highlights II; VCH: New York; pp
203-222, and the references therein.
(2) Nagasawa, T.; Taya, K.; Kitamura, M.; Suzuki, K. J. Am. Chem.
Soc. 1996, 118, 8949-8950.
(3) Easily prepared from the corresponding ester derivative by treatment
with 2.5 equiv of alkynyllithium.
10.1021/ol0156704 CCC: $20.00 © 2001 American Chemical Society
Published on Web 03/10/2001