My PhD dissertation - Institut Fresnel

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1 H NMR: δ = 7.2 (m, 20 H), 7.2 (m, 2 H), 7.05 (dd, J = 8.2, 0.9 Hz, 2 H), 6.84 (d,
J = 9.0 Hz, 2 H), 4.43 (d, J = 7.0 Hz, 2 H), 4.30 (d, J = 7.0 Hz, 2 H), 3.09 (s, 6 H)
ppm.
31 P NMR: δ = -10.8 ppm.
C40H36O4P2 (642.66) calcd. C 74.76% H 5.65%
found C 74.56% H 6.00%.
(-)-(M)[6,6’-Bis(methoxymethoxy)biphenyl-2,2’-diyl]bis(diphenylphosphine) (M-44):
Prepared following the same protocol starting from (+)-(M)-2,2’-dibromo-6,6’-
bis(methoxymethoxy)biphenyl (34; 2.0 g, 4.6 mmol); m.p.107 - 109 °C; [ α ] = -21.9 (c = 1.0,
acetone); ee > 98% [determined by chiral HPLC analysis on Chiracel OD-phase,
cyclohexane/ethanol (1 : 3), 1.0 ml/min]; yield: 1.97 g (66%). For crystallographic data see
Table 6, § 4.5.
(+)-(P)-[6,6’-Bis(methoxymethoxy)biphenyl-2,2’-diyl]bis(diphenylphosphine) (P-44):
Prepared following the same protocol starting from (-)-(P)-2,2’-dibromo-6,6’-
bis(methoxymethoxy)biphenyl (34; 2.0 g, 4.6 mmol); m.p.107 - 109 °C; [ α ] = +22.2
(c = 1.0, acetone); ee > 99% [determined by chiral HPLC analysis on Chiracel OD-phase,
cyclohexane/ethanol (1 : 3), 1.0 ml/min]; yield: 2.10 g (69%).
(±)-(PM)-[6,6’-Bis(methoxymethyl)biphenyl-2,2’-diyl]bis(diphenylphosphine) (45): tert-
Butyllithium (11 mmol) in pentane (7.4 mL) was added dropwise to a solution of (±)-(PM)-
2,2’-dibromo-6,6’-bis(methoxymethyl)biphenyl (41; 1.1 g, 2.7 mmol) in tetrahydrofuran (5.0
mL) at -75 °C. After 30 min, the reaction mixture was treated with a solution of
chlorodiphenylphosphine (1.0 mL, 1.2 g, 5.4 mmol) in tetrahydrofuran (6.0 mL) and
immediately allowed to reach 25 °C. Water was added and the usual extraction procedure
with ethyl acetate (2 × 10 mL) afforded a yellowish amorphous solid which gave colorless
needles after recrystallization from ethyl acetate/hexanes (9:1) mixture; m.p. 249 - 251 °C;
yield: 1.30 g (79%).
1 H NMR (acetone-d6): δ = 7.4 (m, 10 H), 7.3 (m, 10 H), 7.2 (m, 6 H), 3.62 (d, J = 6.5
Hz, 2 H), 3.13 (d, J = 6.5 Hz, 2 H), 2.88 (s, 6 H) ppm.
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