Helvetica Chimica Acta ± Vol. 83 (2000)
1265
Et2O (1.3 ml) were slowly added. The mixture was stirred overnight, and the (S)-propanol (1.29 g, 87%) was
isolated as described for the (Æ)-propanol (see above).
(Æ)-2-[2-(Diphenylphosphino)phenyl]-5,6-dihydro-4-phenyl-4H-1,3-oxazine (4). A mixture of 2-(diphe-
nylphosphino)benzonitrile (2.00 g, 7.0 mmol), (Æ)-3-amino-3-phenylpropan-1-ol (1.26 g, 7.6 mmol), and ZnCl2
(0.95 g, 7.0 mmol) in chlorobenzene (20 ml) under N2 was heated to reflux for 94 h. The mixture was submitted
to CC (4 Â 5 cm, silica gel; with CH2Cl2/hexane 1 :2 (100 ml; removal of benzonitrile), then AcOEt): 4 (0.83 g,
28%). Colorless solid. TLC (AcOEt/hexane): Rf 0.5. 1H-NMR: 7.83 ± 7.86 (m, 1 arom. H); 7.09 ± 7.46 (m, 17
arom. H); 6.88 ± 6.92 (m, 1 arom. H); 4.53 (dd, J 4.9, 7.7, 1 H); 4.06 ± 4.09 (m, 2 H); 1.91 ± 2.00 (m, 1 H); 1.59 ±
1.70 (m, 1 H ).13C-NMR (75 MHz, CDCl3): 157.8 (C(2)); 143.4, 138.5, 138.3, 138.2, 138.0, 137.5, 137.2 (arom. C);
134.0, 133.7, 129.8, 129.2, 128.4, 128.3, 128.1, 126.6 (arom. CH); 63.3 (C(6)); 54.4 (C(4)); 29.2 (C(5)). 31P-NMR:
À6.19. FAB-MS: 422 (100), 344 (19), 317 (23), 304 (48), 289 (21), 183 (29), 117 (45), 105 (21).
(4S)-2-[2-(Diphenylphosphino)phenyl]-5,6-dihydro-4-phenyl-4H-1,3-oxazine ((S)-4). As described for 4,
with 2-(diphenylphosphino)benzonitrile (1.0 g, 3.5 mmol), (3S)-3-amino-3-phenylpropan-1-ol (0.7 g, 3.8 mmol)
and ZnCl2 (0.53 g, 3.5 mmol): 0.42 g (28%) of (S)-4. Colorless solid.
(Æ)-{2-[2-(Diphenylphosphino-kP)phenyl]-5,6-dihydro-4-phenyl-4H-1,3-oxazine-kN]}(h3-1,3-diphenylprop-
2-enyl)palladium(II) Hexafluorophosphate (5). A mixture of [PdCl(h3-diphenylallyl)]2 (100 mg, 0.15 mmol)
and 4 (140 mg, 0.3 mmol) in EtOH(10 ml) was stirred for 1.5 h. The resulting soln. was treated with (NH 4)PF6
(80 mg). After 10 min, the yellow precipitate (250 mg, 97%) was filtered off. Recrystallization from CH2Cl2/
EtOH/hexane 1:3 :3 afforded air-stable crystals suitable for X-ray analysis. 1H-NMR (for numbering, see Fig. 4;
major isomer) 8.28 ± 8.33 (m, 1 arom. H); 6.88 ± 7.72 (m, 22 arom. H); 6.35 ± 6.44 (m, HÀC(300); 2 arom. H);
6.14 ± 6.22 (m, 4 arom. H); 5.72 (dd, J 14.3, 10.1, HÀC(200)); 4.42 ± 4.50 (m, 1 HÀC(6)); 4.19 ± 4.26 (m, 1
HÀC(6)); 3.85 ± 3.90 (m, HÀC(100), HÀC(4)); 1.90 ± 1.99 (m, 1 HÀC(5)); 1.44 ± 1.55 (m, 1 HÀC(5)).
31P-NMR: 20.95 (major); 26.17 (minor); 20.63 (minor).
(Æ)-{2-[2-(Diphenylphosphino-kP)phenyl]-5,6-dihydro-4-phenyl-4H-1,3-oxazine-kN]}(h3-methylbut-2-enyl)-
palladium(II) Hexafluorophosphate (6). A suspension of [PdCl(h3-MeC3H3Me)]2 (80 mg, 0.2 mmol) and of 4
(170 mg, 0.4 mmol) was stirred in EtOH(5 ml) for 1 h. The resulting pale yellow soln. was treated with
(NH4)PF6 and the precipitate collected on a filter and recrystallized from EtOH. 1H-NMR (600 MHz, CDCl3;
for numbering, see Fig. 4): isomer I: 8.13 ± 8.18 (m, 1 arom. H); 7.11 ± 7.80 (m, 16 arom. H); 6.81 ± 6.94 (m, 2
arom. H); 5.05 (dd, J 4.9, 7.7, HÀC(4)); 4.67 ± 4.76 (m, 1 HÀC(6)); 4.35 ± 4.39 (m, 1 HÀC(6)); 4.32 (dd, J
10.3, 14.0, HÀC(200)); 3.07 ± 3.16 (m, HÀC(100)); 2.15 ± 2.17 (m, 1 HÀC(5)); 1.58 ± 1.65 (m, 1 HÀC(5), 1 Me);
0.74 (dd, J 6.3, 13.5, 1 Me); isomer II: 8.02 ± 8.04 (m, 1 arom. H); 7.11 ± 7.80 (m, 16 arom. H); 7.05 ± 7.06 (m, 2
arom. H); 5.39 (dd, J ꢀ 12, HÀC(200)); 5.16 ± 5.20 (m, HÀC(4)); 4.34 ± 4.38 (m, 1 HÀC(6)); 4.12 ± 4.17 (m, 1
HÀC(6)); 3.77 ± 3.81 (m, HÀC(300)); 3.03 ( (dq, J 12.8, 6.0, HÀC(100)); 1.72 ± 1.77 (m, 1 HÀC(5)); 1.32 ±
1.38 (m, 1 HÀC(5)); 1.18 (dd, J 6.2, 10.3, 1 Me); 0.74 (dd, 1 Me); isomer III: 8.13 ± 8.18 (m, 1 arom. H); 7.11 ±
7.80 (m, 16 arom. H); 6.81 ± 6.94 (m, 2 arom. H); 5.35 (dd, J ꢀ 7, 13, HÀC(200)); 4.96 (dd, J 4.8, 10.3, HÀC(4));
4.78 ± 4.83 (m, 1 HÀC(6)); 4.51 ± 4.54 (m, 1 HÀC(6)); 3.78 (m, J ꢀ 7.7, H ÀC(100)); 3.60 (ddq, HÀC(300));
2.36 ± 2.38 (m, 1 HÀC(5)); 1.83 (dd, J 11.0, 6.2, 1 Me); 1.64 ± 1.69 (m, 1 HÀC(5)); 0.30 (t, J 6.9, 1 Me); isomer
IV: 8.23 ± 8.25 (m, 1 arom. H); 7.11 ± 7.80 (m, 16 arom. H); 6.72 ± 6.74 (m, 2 arom. H); 5.54 (sext., J ꢀ 7,
HÀC(300)); 5.10 (dd, J 4.7, 10.3, HÀC(4)); 4.85 ± 4.90 (m, 1 HÀC(6)); 4.49 ± 4.51 (m, 1 HÀC(6)); 3.77 ± 3.81
(dd, HÀC(200)); 3.43 (dq, J 9.8, 6.4, HÀC(100)); 2.27 ± 2.30 (m, 1 HÀC(5)); 1.64 ± 1.71 (m, 1 HÀC(5)); 1.28
(t, J 6.0, 1 Me); 0.83 (dd, J 6.3, 11.6, 1 Me); isomer V: 7.96 ± 7.98 (m, 1 arom. H); 6.6 ± 7.80 (m, 18 arom. H);
5.35 ± 5.41 (m, HÀC(200)); 5.25 ± 5.26 (m, HÀC(4)); 4.14 ± 4.18 (m, HÀC(300)); 3.68 (dq, J 6.0, 11.4,
HÀC(100)); 1.01 (dd, J 9.5, 6.2, 1 Me); 0.87 (dd, J 6.5, 6.6, 1 Me); isomer VI: 1.5 (dd, 1 Me); 0.63 (dd, 1 Me).
31P-NMR: 27.42 (7%); 25.70 (19%); 23.41 (27%); 23.32 (17%); 23.24 (3%); 18.93 (27%).
Palladium-Catalyzed Allylic Alkylation of 1,3-Diphenylprop-2-enyl Acetate Using the BSA Procedure. A
mixture of [Pd(C3H5)Cl]2 (2.4 mg, 6.6 mmol) and (S)-4 (6.7 mg, 15.9 mmol) in CH2Cl2 (0.6 ml) was stirred for
30 min at r.t. To the resulting pale-yellow mixture, a soln. of rac-1,3-diphenylprop-2-enyl acetate (160.3 mg,
0.64 mmol) in CH2Cl2 (3 ml) was added. Then dimethyl malonate (252 mg, 1.9 mmol), N,O-bis(trimethylsilyl)-
acetamide (388 mg, 1.90 mmol), and AcOK (1.1 mg) were added. The mixture was stirred at r.t. for 48 h. Traces
of starting material were detected by TLC (hexane/AcOEt 3 :1). Rf (starting material) 0.45, Rf (product) 0.33.
The soln. was diluted with Et2O (25 ml) and washed twice with ice cold sat. aq. NH4Cl soln. The org. phase was
dried (Na2SO4) and evaporated. CC (SiO2 ; hexane/AcOEt 3 :1) afforded 165 mg (80%) of colorless dimethyl 2-
[(E)-1,3-diphenylprop-2-enyl]propanedioate. Chiral CC (Daicel Chiralcel OD column, l 254 nm, hexane/
iPrOH99 :1, flow rate 0.3 ml/min): tR(R) 38.40, tR(S) 40.88 min; 99% ee for (R)-enantiomer. 1H-NMR: 7.19 ±
7.32 (m, 10 arom. H); 6.49 (d, J 15.6, HÀC(3')); 6.33 (dd, J 8.4, 15.8, HÀC(2')); 4.27 (dd, J 8.4, 10.7,
HÀC(1')); 3.95 (d, J 10.8, HÀC(2)); 3.70 (s, Me); 3.51 (s, Me).