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15. Baker, R. W.; Foulkes, M. A.; Taylor, J. A. J. Chem.
References
Soc., Perkin Trans. 1 1998, 1047.
1. Halterman, R. L. Chem. Rev. 1992, 92, 965.
2. Janiak, C. In Metallocenes; Togni, A.; Halterman, R.
L., Eds.; Wiley-VCH: Weinheim, 1998; pp. 547–623.
3. (a) Negishi, E.; Montchamp, J.-L. In Metallocenes;
Togni, A.; Halterman, R. L., Eds.; Wiley-VCH: Wein-
heim, 1998; pp. 241–319; (b) Hoveyda, A. H.; Morken,
J. P. In Metallocenes; Togni, A.; Halterman, R. L.,
Eds.; Wiley-VCH: Weinheim, 1998; pp. 625–683.
4. (a) Brookings, D. C.; Harrison, S. A.; Whitby, R. J.;
Crombie, B.; Jones, R. V. H. Organometallics 2001, 20,
4574; (b) Kataoka, Y.; Shibahara, A.; Yamagata, T.;
Tani, K. Organometallics 2001, 20, 2431; (c) Schumann,
H.; Stenzel, O.; Dechert, S.; Girgsdies, F.; Halterman,
R. L. Organometallics 2001, 20, 2215.
16. Typical procedure: preparation of (S)-3-(h-methoxyben-
zyl)-1H-indene 22. 1,2-Dibromoethane (0.3 ml, 3.5
mmol) was added dropwise to a stirred suspension of
Mg granules [20 mesh (Aldrich), 1.44 g, 59 mmol] in
dry THF (10 ml) under an argon atmosphere. Upon
cessation of effervescence a solution of o-bromo-(2-
chloroethyl)benzene 7 (3.0 g, 13.7 mmol) in dry THF
(40 ml) was added dropwise at room temperature over
30 min. After stirring overnight, the di-Grignard solu-
tion was added dropwise via cannula to a solution of
methyl (S)-a-methoxyphenylacetate (700 mg, 3.9 mmol)
in dry THF (10 ml) at −78°C over 1 h, and the mix-
ture then allowed to warm slowly to room temperature
over 20 h. The reaction was then quenched by addition
of aqueous NH4Cl (10%), diluted with CH2Cl2, the
organic phase separated and washed with water, dried
(Na2SO4), and the solvent removed under reduced pres-
sure. The crude product was dissolved in CH2Cl2 (50
ml) with p-toluenesulfonic acid monohydrate (50 mg,
0.3 mmol) and the mixture stirred for 4 h at room
temperature under an argon atmosphere. The mixture
was then diluted with CH2Cl2, washed with saturated
aqueous NaHCO3, dried (Na2SO4), and the solvent
removed under reduced pressure. Flash chromatography
eluting with 3% EtOAc/hexane afforded (S)-3-(a-
5. Halterman, R. L. In Metallocenes; Togni, A.; Halter-
man, R. L., Eds.; Wiley-VCH: Weinheim, 1998; pp.
455–544.
6. Schumann, H.; Stenzel, O.; Girgsdies, F.; Halterman,
R. L. Organometallics 2001, 20, 1743.
7. Halterman, R. L.; Tretyakov, A.; Khan, M. A. J.
Organomet. Chem. 1998, 568, 41.
8. Halterman, R. L.; Zhu, C. Tetrahedron Lett. 1999, 40,
7445.
9. Baker, R. W.; Foulkes, M. A.; Turner, P. J. Chem.
Soc., Dalton Trans. 2000, 431.
10. Ellis, W. E.; Hollis, T. K.; Odenkirk, W.; Whelan, J.;
Ostrander, R.; Reingold, A. L.; Bosnich, B.
Organometallics 1993, 12, 4391.
methoxybenzyl)-1H-indene 22 (560 mg, 61%) as
a
colourless oil, [h]D=+6.9 (c 2.9, toluene). The ee of the
product was shown to be >98% by 1H NMR analysis
in the presence of Eu(hfc)3 (ca. 0.7 equiv., ca. 60 mM);
lH (400 MHz, C6D6) 6.40 and 6.47 (each br s) for the
11. Witte, P.; Lal, T. K.; Waymouth, R. M. Organometal-
lics 1999, 18, 4147.
12. (a) Baker, R. W.; Wallace, B. J. Chem. Commun. 1999,
1405; (b) Baker, R. W.; Taylor, J. A. Tetrahedron Lett.
2000, 41, 4471.
13. o-Bromophenylacetone was prepared from o-bromoben-
zaldehyde through condensation with nitroethane fol-
lowed by treatment of the nitropropene with Fe/HCl.
See: Binovic, K.; Vrancea, S.; Grandet, D.; Lebourg, J.
M.; Porquet, R. Chim. Ther. 1968, 3, 313.
indenyl 2-H of the (R)- and (S)-enantiomers, respec-
12
tively. Found: M+, 236.120156.
C
1H1616O requires
17
M+, 236.120115. lH (400 MHz, CDCl3) 3.44 [2H, br s,
(1-H)2], 3.48 (3H, s, OCH3), 5.36 (1H, br s, CH-OMe),
6.44 (1H, br s, 2-H), 7.20–7.53 (9H, m, Ar-H). lC (100
MHz, CDCl3) 144.7, 144.6, 143.2 and 140.0 (each C),
130.9 (CH), 128.3 (2×CH), 127.7 (CH), 127.3 (2×CH),
126.0, 124.7, 123.7, 120.5 and 81.1 (each CH), 56.9
(CH3) and 37.7 (CH2).
14. Vankar, Y. D.; Rao, C. T. J. Chem. Res. Synop. 1985,
7, 232.