3650
A. Mandoli et al. / Tetrahedron: Asymmetry 14 (2003) 3647–3650
(CDCl3, 200 MHz) 7.14–7.32 (m, 5H), 7.11 (d, J=8.7 Hz,
Acknowledgements
2H), 6.86 (d, J=8.7 Hz, 2H), 4.12 (t, J=5.9 Hz, 2H),
3.85 (t, J=5.9 Hz, 2H), 3.39–3.52 (m, 2H), 2.04 (quint,
J=5.9 Hz, 2H), 1.92 (br s, 2H), 1.20–1.30 (m, 6H).
Resonances assigned to the minor (R,S) diastereomer
were present at 3.68–3.80 and 1.30–1.38 ppm. 13C NMR
(CDCl3, 50 MHz) 158.42, 130.43, 128.62, 128.4, 127.89,
127.77, 127.23, 114.52, 65.29, 59.50, 55.59, 55.38, 31.94,
22.94. Resonances assigned to the minor (R,S)
diastereomer were present at 55.06, 54.53 and 21.84 ppm.
10. (a) Van Niel, J. C. G.; Pandit, U. K. Tetrahedron 1985,
41, 6005–6011; (b) Alvaro, G.; Savoia, D.; Valentinetti,
M. R. Tetrahedron 1996, 52, 12571–12586; (c) Suwa, T.;
Sugiyama, E.; Shibata, I.; Baba, A. Synthesis 2000, 789–
800.
11. Data for material P8. C, 84.73%; H, 8.15%; N, 2.24%. IR
(KBr, cm−1) 3439, 2914, 1676, 1607, 1508, 1448, 1235,
1171, 754. 13C NMR (gel-phase, CDCl3, 50 MHz,
aliphatic region) 72.8, 66.7, 64.9, 54.9, 54.3, 45.0–40.0
(polystyrene backbone), 29.8, 25.0.
12. Feringa, B. L.; Pineschi, M.; Arnold, L. A.; Imbos, R.; de
Vries, A. H. M. Angew. Chem., Int. Ed. Engl. 1997, 36,
2620–2623.
13. (a) Greene, N.; Kee, T. P. Synth. Commun. 1993, 23,
1651–1657; (b) Scherer, J.; Huttner, G.; Buchner, M.;
Bakos, J. J. Organomet. Chem. 1996, 520, 45–58.
14. Data for 10. 31P NMR (THF) l 176.2.
15. Data for material P9. C, 78.98%; H, 6.86%; N, 1.38%; P,
2.55%. 13C NMR (gel-phase, CDCl3, 50 MHz, aliphatic
region) 66.6, 65.1, 52.2, 45.0–40.0 (polystyrene back-
bone), 30.0, 22.2. 31P NMR (gel-phase, CDCl3, 120 MHz)
144.2.
16. Data for 12 [(R,S,S):(R,R,S)=92:8]. Rf=0.29 (SiO2, n-
hexane: CH2Cl2=1:1). [h]3D0=−321 (c 0.47, CH2Cl2). 1H
NMR (C6D6, 300 MHz) 6.66–7.68 (m, 26H), 4.50–4.60
(m, 2H), 4.23 (s, 2H), 3.75 (t, J=6.0 Hz, 2H), 3.34 (t,
J=6.0 Hz, 2H), 1.82 (quint, J=6.0 Hz, 2H), 1.54–1.59
(m, 6H). 13C NMR (C6D6, 75 MHz) 158.38, 150.85,
150.76, 150.31, 143.47, 139.21, 135.28, 133.41, 133.31,
133.28, 131.88, 130.93, 130.73, 129.75, 129.58, 129.55,
128.63, 128.50, 128.44, 128.31, 128.08, 127.99, 127.67,
127.59, 127.50, 126.92, 126.46, 126.37, 124.96, 124.75,
122.93, 122.75, 114.11, 72.98, 66.89, 64.86, 52.54, 52.38,
52.16, 51.99, 30.10, 22.06. 31P NMR (C6D6, 120 MHz)
147.1 (92%), 147.3 ppm (8%).
The financial support by M.I.U.R., Universita` di Pisa
(National Project ‘Stereoselezione in Sintesi Organica’)
and Consiglio Nazionale delle Ricerche (C.N.R.) is
gratefully acknowledged.
References
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9. Data for compound
7 [(S,S):(R,S)=90:10]. Rf=0.13
(SiO2, Et2O). [h]D30=−176 (c 1.00, CHCl3). 1H NMR