The Journal of Organic Chemistry
Article
7.44−7.40 (m, 4H), 4.92 (t, J = 2.0 Hz, 4H), 4.58 (t, J = 2.0 Hz, 4H);
13C{1H} NMR (100 MHz, CDCl3) δ 197.8, 139.0, 131.8, 128.2, 128.0,
79.4, 74.5, 73.0.
143.2, 128.1, 127.3, 126.1, 94.0, 71.9, 68.4, 68.0, 67.9, 67.3, 65.9;
HPLC (Chiralcel OD-H column, hexane/i-PrOH = 90/10, 1.0 mL/
min, 210 nm) t1 = 12.7 min, t2 = 19.1 min; [α]2D5 = +77.0° (c 0.9,
CH2Cl2), lit.6a [α]D20 = −89.3° (c 1.01, CH2Cl2) for R enantiomer with
89% ee.
Typical Procedure for Asymmetric Hydrogenation. In a 25
mL Schlenk tube were placed [RuCl2(benzene)]2 (5.0 mg, 0.01 mmol)
and the ligand ((S)-Xyl-SunPhos, 17.2 mg, 0.022 mmol; (S)-SunPhos
15.0 mg, 0.022 mmol). The tube was evacuated and purged with
nitrogen three times before addition of freshly distilled and freeze−
thaw degassed DMF (3 mL). The resulting mixture was heated at 100
°C for 12 min before it was cooled to room temperature, and then
(S,S)-Daipen (6.8 mg, 0.022 mmol) was added under N2. The tube
was vacuumed and purged with nitrogen three times before it was
heated to 40 °C for 4 h. The solvent was removed under vacuum to
give the catalyst as a brownish yellow solid. The catalyst was dissolved
in degassed i-PrOH (4 mL), and then the solution was equally charged
into eight vials which contained 0.25 mmol of substrates, t-BuOK (5
equiv to catalyst), and 0.5 mL of i-PrOH. Then the vials were
transferred into 300 mL autoclaves. The autoclaves were purged three
times with H2, and the required pressure of H2 was set. The contents
of the autoclaves were stirred under specified reaction conditions.
After cooling to ambient temperature and careful release of hydrogen,
the autoclaves were opened and the solvent was evaporated. The
enantiomeric excess was determined by HPLC after the residue was
passed through a short pad of silica gel column with ethyl acetate.
Ferrocenyl(2-methylphenyl)methanol (4b):29 yellow solid; mp
106.3−108.5 °C; 1H NMR (400 MHz, CDCl3) δ 7.48−7.46 (m, 1H),
7.22−7.10 (m, 3H), 5.61 (d, J = 3.6 Hz, 1H), 4.27 (s, 6H), 4.19 (d, J =
17.3 Hz, 2H), 4.10 (s, 1H), 2.50 (d, J = 3.6 Hz, 1H), 2.34 (s, 3H);
13C{1H} NMR (100 MHz, CDCl3) δ 141.3, 134.9, 130.1, 127.2, 125.8,
125.7, 94.5, 68.3, 68.1, 68.0, 67.7, 67.3, 66.8, 19.1; HPLC (Chiralcel
AD-H column, hexane/i-PrOH = 95/5, 0.6 mL/min, 210 nm) t1 =
25.9 min, t2 = 27.7 min; [α]2D5 = +134.9° (c 0.53, CH2Cl2), lit.29 [α]D =
−146.7° (c 1.06, CHCl3) for R enantiomer with 93% ee.
Ferrocenyl(2-chlorophenyl)methanol (4c):28 yellow solid; mp
1
119.4−122.5 °C; H NMR (400 MHz, CDCl3) δ 7.61 (d, J = 7.2
Hz, 1H), 7.31−7.27 (m, 2H), 7.20−7.16 (m, 1H), 5.83 (d, J = 3.2 Hz,
1H), 4.38 (s, 1H), 4.27−4.16 (m, 8H), 2.59 (d, J = 2.8 Hz, 1H);
13C{1H} NMR (100 MHz, CDCl3) δ 140.8, 132.1, 129.2, 128.4, 127.4,
126.8, 93.5, 68.4, 68.1, 67.9, 67.8, 67.5, 66.1; HPLC (Chiralcel OD-H
column, hexane/i-PrOH = 95/5, 0.8 mL/min, 210 nm) t1 = 15.5 min,
t2 = 18.3 min; [α]D25 = +146.1° (c 0.76, CH2Cl2).
Ferrocenyl(4-methoxyphenyl)methanol (4d):18a yellow solid; mp
1
66.2−70.0 °C; H NMR (400 MHz, CDCl3) δ 7.32−7.28 (m, 2H),
1-Ferrocenylethanol (2a):6a yellow solid; mp 76.2−80.8 °C; H
1
6.87−6.84 (m, 2H), 5.44 (d, J = 3.1 Hz, 1H), 4.24−4.21 (m, 6H),
4.19−4.16 (m, 3H), 3.79 (s, 3H), 2.39 (d, J = 3.2 Hz, 1H); 13C{1H}
NMR (100 MHz, CDCl3) δ 158.8, 135.6, 129.0, 127.4, 113.5, 94.2,
71.6, 68.6, 68.4, 68.0, 67.9, 67.2, 65.9, 55.2. (Chiralcel OD-H column,
hexane/i-PrOH = 90/10, 1.0 mL/min, 210 nm) t1 = 15.3 min, t2 =
19.0 min; [α]D25 = +44.2° (c 0.28, CH2Cl2), lit.18a [α]2D0 = −12.8° (c
0.76, CH2Cl2) for R enantiomer with 60% ee.
NMR (400 MHz, CDCl3) δ 4.58−4.52 (m, 1H), 4.22−4.16 (m, 9H),
1.84 (d, J = 4.8 Hz, 1H), 1.44 (d, J = 6.4 Hz, 3H); 13C{1H} NMR (100
MHz, CDCl3) δ 94.6, 68.2, 67.8, 67.8, 66.1, 66.0, 65.5, 23.6; HPLC
(Chiralcel AD-H column, hexane/i-PrOH = 95/5, 0.6 mL/min, 210
nm) t1 = 29.2 min, t2 = 31.8 min; [α]2D5 = −20.3° (c 0.43, CH2Cl2),
lit.6a [α]D20 = +26.9° (c 1.15, CH2Cl2) for S enantiomer with 99.4% ee.
1-Ferrocenyl-1-propanol (2b):18b yellow oil; H NMR (400 MHz,
1
Ferrocenyl(4-trifluoromethylphenyl)methanol (4e):32 yellow
1
CDCl3) δ 4.26−4.23 (m, 2H), 4.20−4.16 (m, 8H), 1.94 (d, J = 2.8 Hz,
1H), 1.73−1.62 (m, 2H), 0.94 (t, J = 7.6 Hz, 3H); 13C{1H} NMR
(100 MHz, CDCl3) δ 94.0, 70.9, 68.2, 67.7, 67.6, 67.1, 65.1, 30.9, 10.3;
HPLC (Chiralcel AS-H column, hexane/i-PrOH = 98/2, 0.6 mL/min,
210 nm) t1 = 13.8 min, t2 = 14.6 min; [α]2D5 = −47.3° (c 0.71, CH2Cl2),
lit.18b [α]D20 = −66.5° (c 4.9, CHCl3) for R enantiomer with 98% ee.
solid; mp 64.5−68.0 °C; H NMR (400 MHz, CDCl3) δ 7.58 (d, J
= 8.0 Hz, 2H), 7.50 (d, J = 8.4 Hz, 2H), 5.49 (d, J = 2.0 Hz, 1H),
4.25−4.23 (m, 7H), 4.19−4.17 (m, 2H), 2.55 (d, J = 2.8 Hz, 1H);
13C{1H} NMR (100 MHz, CDCl3) δ 147.1, 129.9, 129.6, 129.3, 129.0
(q, J = 32.3 Hz), 128.2, 126.4, 125.5, 125.2, 125.1, 125.1, 125.1 (q, J =
3.7 Hz), 122.8, 120.1 (q, J = 270.0 Hz), 94.1, 71.3, 70.3, 68.7, 68.6,
67.7, 65.8; HPLC (Chiralcel AD-H column, hexane/i-PrOH = 95/5,
1.0 mL/min, 210 nm) t1 = 24.9 min, t2 = 29.8 min; [α]2D5 = +70.9° (c
0.80, CH2Cl2).
1-Ferrocenyl-1-butanol (2c):31 yellow oil; H NMR (400 MHz,
1
CDCl3) δ 4.34−4.30 (m, 1H), 4.24−4.15 (m, 9H), 1.92 (d, J = 3.2 Hz,
1H), 1.69−1.60 (m, 2H), 1.50−1.42 (m, 1H), 1.39−1.32 (m, 1H),
0.92 (t, J = 7.2 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 94.4,
69.3, 68.2, 67.8, 67.6, 67.1, 65.1, 40.2, 19.1, 14.0; HPLC (Chiralcel IA-
H column, hexane/i-PrOH = 95/5, 0.8 mL/min, 210 nm) t1 = 16.7
min, t2 = 25.0 min; [α]2D5 = −36.2° (c 1.22, CH2Cl2).
Ferrocenyl(1-naphthyl)methanol (4f):6a yellow solid; mp 158.2−
1
162.5 °C; H NMR (400 MHz, CDCl3) δ 8.14 (d, J = 7.6 Hz, 1H),
7.86−7.84 (m, 1H), 7.78 (d, J = 8.0 Hz, 1H), 7.59 (d, J = 6.8 Hz, 1H),
7.51−7.43 (m, 3H), 6.21 (d, J = 4.0 Hz, 1H), 4.33−4.12 (m, 9H), 2.69
(d, J = 4.0 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ 139.0, 133.6,
130.9, 128.6, 128.1, 125.8, 125.4, 125.3, 123.9, 123.8, 94.2, 68.5, 68.1,
67.8, 67.6, 67.4; HPLC (Chiralcel AS-H column, hexane/i-PrOH =
1-Ferrocenyl-1-decanol (2d). yellow oil; 1H NMR (400 MHz,
CDCl3) δ 4.31−4.28 (m, 1H), 4.25−4.19 (m, 9H), 1.91 (s, 1H),
1.69−1.58 (m, 2H), 1.48−1.40 (m, 1H), 1.34−1.26 (br, 13H), 0.88 (t,
J = 7.2 Hz, 3H); 13C{1H} NMR (100 MHz, CDCl3) δ 94.5, 69.6, 68.2,
67.8, 67.6, 67.1, 65.1, 38.1, 31.8, 29.5, 29.3, 25.95, 22.6, 14.1; IR (KBr,
cm−1) 3928, 3564, 3445, 3094, 2953, 2924, 2853, 1716, 1647, 1465,
1411, 1378, 1275, 1233, 1105, 1040, 1021, 1001, 816, 721, 508, 485,
443; HPLC (Chiralcel OD-H column, hexane/i-PrOH = 99.5/0.5, 0.5
mL/min, 210 nm) t1 = 23.1 min, t2 = 24.2 min; [α]2D5 = −25.0° (c 1.03,
CH2Cl2); HRMS-ESI (m/z) M+ calcd for C20H30FeO 342.1646, found
342.1654.
98/2, 0.8 mL/min, 210 nm) t1 = 23.1 min, t2 = 24.4 min; [α]D25
=
+106.2° (c 1.13, CH2Cl2), lit.6a [α]D21 = −92.69° (c 1.02, CH2Cl2) with
98% ee.
1-Ferrocenyl-2-phenylethanol (4g):31 yellow solid; mp 68.5−70.8
1
°C; H NMR (400 MHz, CDCl3) δ 7.31−7.27 (m, 2H), 7.24−7.17
(m, 3H), 4.60−4.56 (m, 1H), 4.27−4.26 (m, 1H), 4.19−4.06 (m, 8H),
2.95 (d, J = 7.2 Hz, 2H), 2.05 (d, J = 3.2 Hz, 1H); 13C{1H} NMR (100
MHz, CDCl3) δ 138.5, 129.4, 128.2, 126.3, 93.2, 70.8, 68.3, 67.9, 67.7,
67.2, 65.3, 44.9; HPLC (Chiralcel AD-H column, hexane/i-PrOH =
1-Ferrocenyl-4-methyl-1-pentanol (2h). yellow oil; 1H NMR (400
MHz, CDCl3) δ 4.28−4.14 (m, 10H), 1.95 (s, 1H), 1.69−1.51 (m,
3H), 1.39−1.28 (m, 1H), 1.23−1.15 (m, 1H), 0.88 (d, J = 6.4 Hz,
6H); 13C{1H} NMR (100 MHz, CDCl3) δ 94.6, 69.9, 68.2, 67.8, 67.6,
67.2, 65.1, 36.0, 35.1, 27.9, 22.6, 22.5; IR (KBr, cm−1) 3928, 3564,
3439, 3094, 2953, 2933, 2864, 1647, 1467, 1410, 1384, 1365, 1262,
1233, 1105, 1041, 1020, 1000, 886, 816, 509, 484; HPLC (Chiralcel
AD-H column, hexane/i-PrOH = 95/5, 0.8 mL/min, 210 nm) t1 =
14.9 min, t2 = 18.3 min; [α]D25 = −32.5° (c 0.72, CH2Cl2); HRMS-ESI
(m/z) M+ calcd for C16H22FeO 286.1020, found 286.1012.
95/5, 1.0 mL/min, 210 nm) t1 = 18.2 min, t2 = 24.0 min; [α]D25
−4.1° (c 1.03, CH2Cl2).
=
1-Ferrocenyl-3-phenyl-1-propanol (4h):33 yellow solid; mp 57.8−
1
61.0 °C; H NMR (400 MHz, CDCl3) δ 7.31−7.26 (m, 2H), 7.23−
7.17 (m, 3H), 4.35−4.31 (m, 1H), 4.26 (s, 1H), 4.19 (s, 8H), 2.84−
2.77 (m, 1H), 2.74−2.66 (m, 1H), 2.04−1.91 (m, 3H); 13C{1H} NMR
(100 MHz, CDCl3) δ 141.9, 128.4, 128.2, 125.7, 93.9, 68.6, 68.2, 67.9,
67.7, 67.0, 65.4, 39.5, 32.1; HPLC (Chiralcel OD-H column, hexane/i-
PrOH = 90/10, 0.8 mL/min, 210 nm) t1 = 14.0 min, t2 = 21.3 min;
[α]2D5 = −8.4° (c 0.95, CH2Cl2).
Ferrocenylphenylmethanol (4a):6a yellow solid; mp 77.5−79.0 °C;
1H NMR (400 MHz, CDCl3) δ 7.40−7.38 (m, 2H), 7.34−7.31 (m,
2H), 7.27−7.25 (m, 1H), 5.47 (d, J = 3.2 Hz, 1H), 4.23−4.17 (m,
9H), 2.46 (d, J = 3.2 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3) δ
1,1′-Bis(1-hydroxyethyl)ferrocene (6a):15b yellow solid; mp 67.8−
1
69.2 °C; H NMR (400 MHz, CDCl3) δ 4.63 (q, J = 6.4 Hz, 2H),
4.20−4.15 (m, 8H), 3.11 (d, J = 2.4 Hz, 2H), 1.40 (d, J = 6.4 Hz, 6H);
E
J. Org. Chem. XXXX, XXX, XXX−XXX