My PhD dissertation - Institut Fresnel

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13 C NMR (acetone-d6): δ = 133.4 (d, J = 10.4 Hz), 133.1 (d, J = 9.0 Hz), 132.8 (d,
J = 12.4 Hz), 132.6 (d, J = 13.0 Hz), 132.3 (d, J = 3.0 Hz), 132.1 (d, J = 3.0 Hz),
130.3 (d, J = 3.1 Hz), 129.2 (d, J = 11.2 Hz), 128.9 (d, J = 12.2 Hz), 127.3, 71.8,
58.0 ppm.
31 P NMR (acetone-d6): δ = -13.0 ppm.
C40H36O2P2 (610.66) calcd. C 78.67% H 5.94%
found C 78.74% H 6.01%.
(-)-(M)-[6,6’-Bis(methoxymetyl)biphenyl-2,2’-diyl]bis(diphenylphosphine) (M-45): Prepared
following the same protocol starting from (+)-(M)-2,2’-dibromo-6,6’-
bis(methoxymethyl)biphenyl (41; 1.0 g, 2.5 mmol); colorless needles (from ethyl
acetate/hexane); m.p. 199 - 201 °C; [ ] 20
α D = -41.9 (c = 0.5, chloroform); ee > 98.5%
[determined by chiral HPLC analysis on Chiracel OD-phase, cyclohexane/ethanol (1 : 3),
1.0 ml/min]; yield: 1.08 g (71%). For crystallographic data see Table 6, § 4.5.
(+)-(P)-[6,6’-Bis(methoxymetyl)biphenyl-2,2’-diyl]bis(diphenylphosphine) (P-45): Prepared
following the same protocol starting from (-)-(P)-2,2’-dibromo-6,6’-bis(methoxymethyl)biphenyl
(41; 1.0 g, 2.5 mmol); colorless needles (from ethyl acetate/hexane); m.p. 198 - 199 °C;
[ ] 20
α D
= +41.0 (c = 0.49, chloroform); ee 99% [determined by chiral HPLC analysis on Chiracel
OD-phase, cyclohexane/ethanol (1 : 3), 1.0 ml/min]; yield: 1.13 g (74%).
4.4 Coalescence Studies of Dilithiobiphenyl Species
Sample preparation: The dibromobiphenyl (34 or 41; 0.70 mmol) in perdeuterated
tetrahydrofuran (3.0 mL) was added to a solution of tert-butyllithium (2.8 mmol) dissolved in
precooled (-75 °C) perdeuterated tetrahydrofuran (5.0 mL). By means of a precooled pipet, an
aliquot was withdrawn (1.0 mL) and transferred into a nitrogen purged 5 mm NMR tube,
which was plunged into liquid nitrogen before being sealed under vacuum.