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the residue treated with CH2Cl2 (300 mL). The resulting
solution was extracted with a saturated solution of
NaHCO3 (150 mL). The organic phase was dried over
Na2SO4 and evaporated under reduced pressure to give
an oil, which was purified by chromatography (hexane/
AcOEt 7:3). Yield 7.4g, 84%. C 14H15NOS Fw ¼ 245.34.
1H, J ¼ 6.8 Hz); 3.88 (dd, 1H, J ¼ 7.6, 7.8 Hz);. 3.95–
4.04 (m, 1H); 4.16 (dd, 1H, J ¼ 7.6, 8.9 Hz); 7.28–7.49
(m, 12H); 7.65–7.69 (m, 1H); 8.57 (d, 1H, J ¼ 8.2 Hz).
13C NMR (75 MHz, CDCl3): d 18.7; 19.0; 32.9; 69.5;
72.5; 121.8; 124.6; 124.7 (d, J ¼ 1.4Hz); 124.9; 128.0 (d,
J ¼ 16.3 Hz); 128.3 (d, J ¼ 7.5 Hz); 128.4(d, J ¼ 7.5 Hz);
129.1; 129.2; 133.5 (d, J ¼ 21.2 Hz); 134.0 (d,
J ¼ 21.2 Hz); 136.9 (d, J ¼ 39.4Hz); 137.0 (d, J ¼
40.1 Hz); 139.5; 141.8; 147.6 (d, J ¼ 42.1 Hz); 159.54.
31P (124MHz, CDCl 3): d )12.4. GC–MS 429 (Mþ, 4 );
358 (100); 338 (48); 239 (40); 41 (50). Element. Anal.
Calcd for C26H24NOPS: C, 72.71; H, 5.63; N, 3.26.
Found: C, 72.68; H, 5.60; N, 3.28.
½a ¼ )45.0 (c 1.09, CHCl3). 1H NMR (CDCl3,
D
300 MHz): d 0.99 (d, 3H, J ¼ 6.7 Hz); 1.11 (d, 3H,
J ¼ 6.7 Hz); 1.90 (sept, 1H, J ¼ 6.7 Hz); 4.11 (dd, 1H,
J ¼ 7.6, 15.2 Hz); 4.16–4.23 (m, 1H); 4.38 (dd, 1H,
J ¼ 7.4, 9.1 Hz); 7.37–7.52 (m, 2H); 7.82–7.90 (m, 1H);
8.07 (s, 1H); 8.78–8.83 (m, 1H). 13C NMR (CDCl3,
75 MHz): d 18.7; 19.2; 33.3; 69.4; 73.3; 122.6; 125.1;
125.3; 125.5; 131.9; 137.1; 140.3; 159.3. GC–MS: 245
(Mþ, 15); 202 (100); 174(28); 147 (32). Element. Anal.
Calcd for C14H15NOS: C, 68.54; H, 6.16; N, 5.71.
Found: C, 68.51; H, 6.13; N, 5.68.
4.1.5. 2-(2-Diphenylphosphino)-benzo[b]thiophene-3-yl-4-
tert-butyl-4,5-dihydrooxazole 10. Compound 10 was
prepared following the procedure described for com-
pound 9. Yield 0.638 g, 52%. C27H26NOPS Fw ¼ 443.54.
4.1.2. 2-Benzo[b]thiophene-3-yl-4-tert-butyl-4,5-dihydro-
oxazole 7. Compound 7 was prepared following the
procedure described for compound 6. Yield 0.8 g, 70%.
½a ¼ )52.9 (c 1.04, CHCl3). 1H NMR (CDCl3,
D
300 MHz): d 0.81 (s, 9H); 3.90–5.15 (m, 3H); 7.27–7.46
(m, 12H); 7.64–7.69 (m, 1H); 8.56–8.62 (m, 1H). 13C
NMR (CDCl3, 75 MHz): d 26.0; 34.0; 68.2; 76.3; 121.8;
124.9; 125.0; 125.1; 125.2; 128.6 (d, J ¼ 7.7 Hz); 129.4
(d, J ¼ 15.5 Hz); 133.7 (d, J ¼ 20.7 Hz); 134.2 (d,
J ¼ 20.7 Hz); 137.1 (d, J ¼ 29.4Hz); 137.5 (d,
J ¼ 30.4Hz); 139.8; 142.1; 147.9; (d, J ¼ 42.5 Hz); 159.8.
31P (124MHz, CDCl 3): d )12.4. GC–MS 443 (Mþ, 6);
386 (61); 358 (100); 239 (30). Element. Anal. Calcd for
C27H26NOPS: C, 73.11; H, 5.91; N, 3.16. Found: C,
73.13; H, 5.92; N, 3.15.
C15H17NOS Fw ¼ 259.37. ½a ¼ )56.1 (c 0.9, CHCl3).
D
1H NMR (CDCl3, 300 MHz): d 1.02 (s, 9H); 4.11–4.23
(m, 2H); 7.37–7.52 (m, 2H); 7.87 (d, 2H, J ¼ 8.2 Hz);
8.08 (s, 1H); 8.79 (d, 1H, J ¼ 7.9 Hz). 13C NMR (CDCl3,
75 MHz) d: 26.2; 34.3; 67.8; 122.6; 124.7; 125.1; 125.3;
125.5; 131.8; 137.2; 140.3; 159.1. GC–MS 260 ([M+1]þ,
100); 386 (61); 358 (100); 239 (30). Element. Anal. Calcd
for C15H17NOS: C, 69.46; H, 6.61; N, 5.40. Found: C,
69.43; H, 6.58; N, 5.38.
4.1.3. 2-Benzo[b]thiophene-3-yl-4-phenyl-4,5-dihydroox-
azole 8. Compound 8 was prepared following the pro-
cedure described for compound 6. Yield 1.35 g, 84%.
4.1.6. 2-(2-Diphenylphosphino)-benzo[b]thiophene-3-yl-4-
phenyl-4,5-dihydrooxazole 11. Compound 11 was pre-
pared following the procedure described for compound
9. Yield 0.89 g, 52%. C29H22NOPS Fw ¼ 463.54.
C17H13NOS Fw ¼ 279.36. ½a ¼ )55 (c 0.67, CHCl3). 1H
D
NMR (CDCl3, 300 MHz): d 4.24 (dd, 1H, J ¼ 8.1,
8.1Hz); 4.77 (dd, 1H, J ¼ 8.2, 10.1 Hz); 5.51 (dd, 1H,
J ¼ 8.2, 10.0 Hz); 7.30–7.35 (m, 7H); 7.82–7.92 (m, 1H);
8.22 (s, 1H); 8.87–8.92 (m, 1H). 13C NMR (CDCl3,
75 MHz): d 70.7; 74.0; 126.2; 124.3; 125.3; 125.4; 125.6;
127.0; 127.8; 129.0; 132.8; 137.0; 140.3; 142.8; 160.8.
GC–MS 280 ([M+1]þ. Element. Anal. Calcd for:
C17H13NOS: C, 73.09; H, 6.08; N, 5.01. Found: C, 73.05;
H, 6.10; N, 5.66.
½a ¼ )5.4(
c
0.92, CHCl3). 1H NMR (CDCl3,
D
300 MHz): d 3.96 (dd, 1H, J ¼ 8.3, 8.3 Hz); 4.56 (dd, 1H,
J ¼ 8.3, 10.3 Hz); 5.34(dd, 1H, J ¼ 8.8, 10.3 Hz); 7.04–
7.09 (m, 2H); 7.22–7.52 (m, 15H); 7.58–7.72 (m, 1H);
8.60–8.66 (m, 1H). 13C NMR (75 MHz, CDCl3): d 70.1;
74.1; 121.7; 125.0; 125.1; 125.3; 126.9; 127.5; 127.8;
128.7; 128.8 (d, J ¼ 7.7 Hz); 129.6 (d, J ¼ 10.9 Hz); 133,9
(d, J ¼ 21.3 Hz); 134.3 (d, J ¼ 1.3 Hz); 137.0
(J ¼ 20.6 Hz); 137.2 (d, J ¼ 16.6 Hz); 139.8; 142.0; 142.6;
148.9 (d, J ¼ 42.8 Hz); 161.3. 31P (124MHz, CDCl 3): d
)12.4. GC–MS 463 (Mþ, 4); 358 (100); 296 (12); 239
(18). Element. Anal. Calcd for C27H22NOPS: C, 75.14;
H, 4.78; N, 3.02. Found: C, 75.15; H, 4.80; N, 3.06.
4.1.4. 2-(2-Diphenylphosphino)-benzo[b]thiophene-3-yl-4-
a solution of
iso-propyl-4,5-dihydrooxazole 9. To
benzo[b]thiophene oxazoline 6 (0.92 g, 3.83 mmol.) in
Et2O (10 mL) at )78 ꢁC, a solution of 1.6 M BuLi in
hexane (2.63 mL, 4.20 mmol) was added and the result-
ing suspension agitated at )78 ꢁC for 1.5 h. Diphenyl-
chlorophosphine (0.69 mL, 3.83 mmol) was added at
)78 ꢁC, and the reaction mixture warmed to room
temperature and stirred for 30 min. The reaction was
quenched by adding water (30 mL) and pentane (40 mL).
The organic layer was separated, dried over Na2SO4 and
purified by chromatography (hexane/ether 9:1). Yield
4.1.7. Catalytic enantioselective reduction of acetophe-
none with Ru(HetPHOX). Ru(PPh)3Cl2 (9 mg,
0.01 mmol) and the HetPHOX ligand (0.013 mmol) were
dissolved under an inert atmosphere in a flask contain-
ing dried and degassed iPrOH (5 mL). The flask was
heated at reflux for 30 min, and then a solution of ace-
tophenone (10 mmol) in iPrOH (3 mL) added. The
mixture was stirred for 15 min and then a solution of
NaOH (10 mg, 0.25 mmol) in 2 mL of iPrOH added and
the mixture stirred for 30 min. The solvent was evapo-
0.754g, 79%. C 26H24NOPS Fw ¼ 429.51. ½a ¼ )74.0. (c
D
1
0.96, CHCl3). H NMR (CDCl3, 300 MHz): d 0.8 (d,
3H, J ¼ 6.8 Hz); 0.90 (d, 3H, J ¼ 6.8, 7.6 Hz); 1.69 (sept,