R.H. Wallace, K.K. Zong / Journal of Organometallic Chemistry 581 (1999) 87–91
91
mmHg) to afford the product as a clear oil (80%).
1H-NMR (360 MHz, CDCl3) l 7.41–7.20 (m, 5H), 5.93
(d, J=1.7 Hz, 1H), 5.49 (d, J=1.7 Hz, 1H), 3.85–3.82
(m, 4H), 1.55–1.54 (m, 4H), 1.35–1.32 (m, 4H), 0.91–
0.89 (m, 6H). 13C-NMR (90 MHz, CDCl3) l 141.50,
128.48, 127.49, 127.15, 126.34, 122.41, 64.27, 33.70,
18.95, 13.80.
2H), 1.46 (s, 3H), 1.40 (s, 3H), 1.30 (s, 3H), 1.15 (d,
J=10.9 Hz, 1H), 0.85 (s, 3H). 13C-NMR (90 MHz,
CDCl3) l 155.22, 130.11, 129.67, 128.55, 126.18, 86.98,
78.74, 51.18, 44.69, 39.34, 38.18, 35.21, 35.19, 30.19,
28.44, 27.00, 26.39, 23.93, 23.73, 23.68.
Acknowledgements
2.9. Preparation of cycloadducts from 11
We would like to thank the Research Grants Com-
mittee of The University of Alabama, Armstrong At-
lantic State University (AASU), and The Research and
Scholarship Grants Committee of AASU for support-
ing this work. We would also like to thank Chuck
Rawlinson for assistance in obtaining specific rotation
data.
A solution of 11 (974 mg, 1.55 mmol) and phenylhy-
droximic acid chloride (313 mg, 2.01 mmol) in freshly
distilled THF (15 ml) was cooled to 0°C. Triethylamine
(203 mg, 2.01 mmol) in THF (5 ml) was added drop-
wise over 30 min and stirred for 2 h. A white solid
(triethylamine hydrochloride) was filtered through a
glass frit under pressure (argon) and the filtrate was
used in the next reaction.
2.10. Cycloadduct–diethanolamine complex
References
[1] (a) D.P. Curran, in: C.T. Greenwich, D.P. Curran (Eds.), Ad-
vances in Cycloaddition, vol. 1, JAI Press, Greenwich, CT, p.
280. (b) P. Grunanger, P. Vita-Finzi, in: E.C. Taylor (Ed.),
Isoxazoles Part I, Wiley, New York, 1991, p. 417. (c) P.
Caramella, P. Grunanger, in: A. Padwa (Ed.), 1,3-Dipolar Cy-
cloaddition Chemistry, vol. 1, Wiley-Interscience, 1984, p. 291.
(d) A.P. Kozikowski, Acc. Chem. Res. 17 (1984) 410. (e) V.
Jager, I. Muller, Tetrahedron 41 (1985) 3519.
[2] (a) D.S. Matteson, Tetrahedron 45 (1989) 1859. (b) A. Pelter, K.
Smith, H.C. Brown, Borane Reagents, Academic Press, New
York, 1988. (c) M.V. Rangaishenvi, B. Singaram, H.C. Brown,
Org. Chem. 56 (1991) 3286.
[3] (a) K.M. Sadhu, D.S. Matteson, Organometallics 4 (1985) 1687.
(b) T.J. Michnick, D.S. Matteson, Synlett. (1991) 631. (c) H.C.
Brown, S.M. Singh, M.V. Rangaishenvi, J. Org Chem. 51 (1986)
3150.
[4] (a) G. Bianchi, A. Cogoli, P. Grunanger, J. Organomet. Chem. 6
(1966) 598. (b) G. Bianchi, A. Cogoli, P. Grunanger, Ric. Sci.
(1966) 132.
[5] (a) R.H. Wallace, K.K. Zong, M.P. Schoene, Current Topics in
The Chemistry of Boron, Special Publication of the Royal
Society of Chemistry, Cambridge, UK, 1994, pp. 78–81. (b)
R.H. Wallace, M. Gotz, M. McCutchen, in preparation.
[6] R.H. Wallace, K.K. Zong, Tetrahedron Lett. 33 (1992) 6941.
[7] (a) R.H. Wallace, J. Liu, A. Eddings, Tetrahedron Lett. 39
(1997) 6795. (b) R.H. Wallace, J. Liu, K.K. Zong, A. Eddings,
Tetrahedron Lett. 39 (1997) 6791.
[8] R.H. Wallace, Y. Lu, J. Liu, J. Atwood, Synlett. (1992) 992.
[9] D.S. Matteson, J. Am. Chem. Soc. 82 (1960) 4228.
[10] K. Marasasaka, Synthesis (1991) 1.
[11] (a) A.K. Beck, B. Bastani, D.A. Plattner, W. Petter, D. Seebach,
H. Braunschweiger, P. Gysi, L.L.Vecchia, Chimia 45 (1991) 238.
(b) H.W. Yang, D. Romo, Tetrahedron Lett. 39 (1998) 2877.
[12] D.S. Matteson, J. Am. Chem. Soc. 84 (1962) 3712.
[13] D.S. Matteson, R.A. Bowie, G. Srivastava, J. Organomet. Chem.
16 (1969) 33.
The solution above was treated with diethanolamine
(210 mg, 2.0 mmol) at r.t. White solids began to form
within 30 min. The reaction was stirred for 3 h and the
solid was collected by vacuum filtration (ca. 85%). The
product was pure enough for analytical purposes. The
optically pure cycloadduct was obtained from recrystal-
lization in acetone or toluene. M.p. 206–210°C. 1H-
NMR (360 MHz, CDCl3) l 7.61–7.55 (m, 2H),
7.45–7.31 (m, 3H), 6.11 (s, 1H), 4.15–3.89 (m, 4H),
3.58–3.38 (m, 3H), 3.02–2.81 (m, 3H), 1.22 (s, 3H).
13C-NMR (90 MHz, CDCl3) l 157.12, 130.50, 129.51,
128.52, 126.53, 63.38, 63.19, 52.27, 52.16, 44.47, 23.82
2.11. Phenyl-5,5-methyl-pinanylboronat-Z2-isoxazoline
To a suspension of the diethanolamine complex
above (363 mg, 1.40 mmol) and (+)-pinanediol (238
mg, 1.40 mmol) in Et2O (6 ml) was added 4–5 drops of
6 M HCl at r.t. As the reaction proceeded, it became
clear. The mixture was stirred for 3 h and the organic
layer was vacuum-filtered through a short column
packed with MgSO4. The filtrate was concentrated un-
der reduced pressure and further concentrated by vac-
uum pump (0.05 mmHg) to afford the product as a
clear oil (455 mg, 100%). [h]2D0= +10.63° (c=1.3,
1
CH2Cl2). B.p. 119–121°C (0.05 mmHg). H-NMR (360
MHz, CDCl3) l 7.75–7.65 (m, 2H), 7.45–7.35 (m, 3H),
4.41 (dd, J=8.8, 1.7 Hz, 1H), 3.52 (d, J=16.2 Hz,
1H), 3.06 (d, J=16.2 Hz, 1H), 2.41–2.30 (m, 1H),
2.29–2.25 (m, 1H), 2.13–2.10 (m, 1H), 1.95–1.93 (m,
.