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1
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0028299980
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1) (a) G. Brenchley, E. Merifield, M. Wills and M. Fedouloff, Tetrahedron Lett., 1994, 35, 2791.
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Tetrahedron Lett.
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, pp. 2791
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Brenchley, G.1
Merifield, E.2
Wills, M.3
Fedouloff, M.4
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2
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0029074773
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(b) G. Brenchley, M. Fedouloff, M. F. Mahon, K. C. Molloy and M. Wills, Tetrahedron, 1995, 51, 10581.
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(1995)
Tetrahedron
, vol.51
, pp. 10581
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Brenchley, G.1
Fedouloff, M.2
Mahon, M.F.3
Molloy, K.C.4
Wills, M.5
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3
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0041768560
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2) The significance of the array of four aromatic rings has been addressed in detail, for example; (a) R. Noyori, Chem. Soc. Rev., 1989, 18, 225.
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(1989)
Chem. Soc. Rev.
, vol.18
, pp. 225
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Noyori, R.1
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5
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0028882906
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and references therein. See also reference 3
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(c) D. Seebach, E. Devaquet, A. Ernst, M. Hagakawa, F. N. M. Kuhnle, W. B. Schweiser and B. Weber, Angew. Chem. Int. Edn. Engl., 1995, 78, 1636 and references therein. See also reference 3.
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(1995)
Angew. Chem. Int. Edn. Engl.
, vol.78
, pp. 1636
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Seebach, D.1
Devaquet, E.2
Ernst, A.3
Hagakawa, M.4
Kuhnle, F.N.M.5
Schweiser, W.B.6
Weber, B.7
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8
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85030270496
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note
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4) The following are representative of the methods we attempted; 1,2-dibromoethane in THF, DMF or DMSO using sodium hydride (with and without added silver salts or 18-crown-6), butyllithium. potassium carbonate, P4 superbase; also with sodium hydride as base in THF: ethane-1,2-diol(bis)trifluorosulfonate, 1,2 diiodoethane, 1,3 dibromopropane, oxalyl chloride; ethane-1,2-diol with triphenylphosphine and DEAD.
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9
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0001767033
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5) A sample of S-5 was generously provided by SmithKline Beecham, however for the synthesis of the antipodal diphosphine ligand it was necessary to prepare R-5 by the asymmetric reduction of o-bromoacetophenone using the method reported by Evans; D. A. Evans, S. G. Nelson, M. R. Gagne and A. R. Muci, J. Am. Chem. Soc., 1993, 115, 9800.
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(1993)
J. Am. Chem. Soc.
, vol.115
, pp. 9800
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Evans, D.A.1
Nelson, S.G.2
Gagne, M.R.3
Muci, A.R.4
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10
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33751385202
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6) A. S. Thompson, G. R. Humphrey, A. M. Demarco, D. J. Mathre and E. J. J. Grabowski, J. Org. Chem., 1993, 58, 5886.
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(1993)
J. Org. Chem.
, vol.58
, pp. 5886
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Thompson, A.S.1
Humphrey, G.R.2
Demarco, A.M.3
Mathre, D.J.4
Grabowski, E.J.J.5
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11
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85030268000
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note
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7) The methine protons in 2a and 2e appear as quartets at δ4.98 and 5.52 ppm respectively. Their cis-diastereoisomers have corresponding resonances at δ4.86 and 5.08 ppm (multiplet and sextet respectively). The same pattern is repeated in a derivative of 2a containing a 2-pyrollidylethyl group in the nitrogen atom, the relative configuration in which, like 2e, has been confirmed by X-ray crystallography. Compound (SpS)(SpS)-1 displayed a quartet at δ4.63 ppm for the methine resonance.
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12
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6844254916
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8) For an excellent recent review see B. M. Trost, Chem. Rev. 1996, 96, 395.
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(1996)
Chem. Rev.
, vol.96
, pp. 395
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Trost, B.M.1
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13
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0000740766
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1 Hydrogenation product 9: chiral HPLC on Chiralcel OJ column; M. J. Burk, J. E. Feaster, W. A. Nugent and R. L. Harlow, J. Am. Chem.Soc., 1993, 115, 10125.
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(1993)
J. Am. Chem.soc.
, vol.115
, pp. 10125
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Burk, M.J.1
Feaster, J.E.2
Nugent, W.A.3
Harlow, R.L.4
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14
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0001540849
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10a - 10c: Chiral HPLC, Chiralcel OD column, 1.0-8% isopropanol (depending on sample) in hexane containing 0.1% diethylamine. 1-(1-Naphthyl)ethanol; chiral HPLC on Chiralcel OJ column using 8% isopropanol in hexane containing 0.1% diethylamine. Flow rates of 0.5-1ml/min give excellent separations although exact elution times and efficiency of separation depend on exact column dimensions and history. Further details will be given in a full paper. Absolute configurations confirmed for 10a to 10c and 1-(1-naphthyl)ethanol by optical rotation sign as given in ref. 5 and (a) M. B. Carter, B. Schiott, A. Gutierrez and S. L. Buchwald, J. Am. Chem. Soc., 1994, 116, 11667,
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(1994)
J. Am. Chem. Soc.
, vol.116
, pp. 11667
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Carter, M.B.1
Schiott, B.2
Gutierrez, A.3
Buchwald, S.L.4
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