64
M. Takahashi et al. / Tetrahedron: Asymmetry 19 (2008) 60–66
CH2), 4.75 (br s, 2H, CH), 1.43 (s, 18H, CH3). Anal. Calcd
for C33H40N2O6: H, 7.19; C, 70.69; N, 5.00. Found for
C33H40N2O6: H, 7.15; C, 70.64; N, 5.02.
J = 18.0 Hz, 1H, CH2=CH), 5.49 (br s, 2H, NH), 5.25
(d, J = 12.0 Hz, 1H, CH2@CH), 4.98 (s, 2H, CH2), 4.97
(s, 2H, CH2), 4.78 (br s, 2H, CH), 1.43 (s, 18H, CH3).
13C NMR (75 MHz, CDCl3, d): 128.8, 128.2, 128.0,
127.7, 126.6, 114.9, 70.1, 28.6. Anal. Calcd for
C40H46N2O6: H, 7.12; C, 73.82; N, 4.30. Found for
C40H46N2O6: H, 7.11; C, 73.82; N, 4.25.
4.3.2. Compound 6b. Prepared according to the above
procedure using 2.8 g (6.30 mmol) of 5, 10 mL of DMF,
1.66 g (6.93 mmol) of 4-(4-bromobutyl)styrene and 2.61 g
(18.9 mmol) of K2CO3 gave 1.72 g (2.85 mmol) of 2c as a
white solid. Yield 45%. Rf = 0.20 (hexane–EtOAc 3:1).
Mp 77–78 °C. [a]D = ꢀ9.6 (c 1.00, CHCl3). 1H NMR
(300 MHz, CDCl3, d): 7.32 (d, J = 8.4 Hz, 2H, Ar-H),
7.13 (d, J = 8.4 Hz, 2H, Ar-H), 6.90 (d, J = 8.4 Hz, 2H,
Ar-H), 6.85 (d, J = 8.4 Hz, 2H, Ar-H), 6.68 (dd, J = 18.0,
11.0 Hz, 1H, CH2@CH), 6.65 (d, J = 8.4 Hz, 2H, Ar-H),
6.61 (d, J = 8.7 Hz, 2H, Ar-H), 5.69 (d, J = 18.0 Hz, 1H,
CH2@CH), 5.66 (br s, 2H, NH), 5.18 (d, J = 12.0 Hz,
1H, CH2@CH), 4.74 (br s, 2H, CH), 3.85 (br s, 2H,
CH2), 2.64 (br s, 2H, CH2), 3.85 (br s, 2H, CH2), 1.89
(br s, 2H, CH2), 1.43 (s, 18H, CH3). 13C NMR (75 MHz,
CDCl3, d): 142.1, 136.9, 128.8, 126.4, 118.5, 115.6, 110.6,
88.9, 67.9, 35.5, 29.0, 28.6, 28.0. Anal. Calcd for
C36H46N2O6: H, 7.69, C, 71.73, N, 4.65. Found for
C36H46N2O6: H, 7.78, C, 70.26, N, 5.09.
4.3.5. Compound 7c. In the same manner, 0.633 g
(1.05 mmol) of 6b, 5 mL of DMF, 0.13 mL (0.30 g;
2.10 mmol) of CH3I and 0.435 g (3.15 mmol) of K2CO3
gave 0.506 g (0.82 mmol) of 7c as a white solid. Yield
>99%. Rf = 0.40 (hexane–EtOAc 3:1). Mp 133–134 °C.
1
[a]D = ꢀ6.5 (c 1.00, CHCl3). H NMR (300 MHz, CDCl3,
d): 7.32 (d, J = 7.8 Hz, 2H, Ar-H), 7.14 (d, J = 7.8 Hz, 2H,
Ar-H), 6.97–6.93 (m, 4H, Ar-H), 6.71 (d, J = 5.4 Hz, 2H,
Ar-H), 6.69 (dd, J = 18.0, 11.0 Hz, 1H, CH2@CH), 6.68
(d, J = 4.8 Hz, 2H, Ar-H), 5.70 (d, J = 17.4 Hz, 1H,
CH2@CH), 5.47 (br s, 2H, NH), 5.19 (d, J = 11.1 Hz,
1H, CH2@CH), 4.77 (br s, 2H, CH), 3.87 (br s, 2H,
CH2), 3.72 (s, 3H, CH3), 2.65 (br s, 2H, CH2), 1.89 (br s,
2H, CH2), 1.43 (s, 18H, CH3). 13C NMR (75 MHz, CDCl3,
d): 142.2, 136.9, 135.4, 128.8, 126.4, 114.5, 114.0, 113.2,
55.4, 35.5, 28.6, 28.0. Anal. Calcd for C36H48N2O6: H,
7.84; C, 72.05; N, 4.54. Found for C36H48N2O6: H, 7.85;
C, 71.18; N, 4.61.
4.3.3. (R,R)-N,N0-Di(tert-butoxycarbonyl)-1-(p-methoxy-
phenyl)-2-(p-(p-vinyl-benzyloxy)phenyl)-1,2-diaminoethane
7a. A 30 mL round-bottomed flask equipped with a mag-
netic stirring bar was charged with 0.728 g (1.30 mmol) of
6a and 5 mL of DMF under nitrogen. To this solution,
0.16 mL (0.37 g; 2.60 mmol) of CH3I and 0.539 g
(3.90 mmol) of K2CO3 was added. After the mixture was
stirred for 24 h, DMF was evaporated under reduced pres-
sure. The residual solid was dissolved in chloroform, and
washed with water three times, dried over anhydrous
magnesium sulfate. After the solvent was removed in
vacuo, the residue was purified by silica gel column chro-
matography (hexane–EtOAc 3:1). Removal of solvent
under reduced pressure gave 0.748 g (1.30 mmol) of 7a as
a white solid. Yield >99%. Rf = 0.30 (hexane–EtOAc
3:1). Mp 158–160 °C. [a]D = ꢀ4.2 (c 1.00, CHCl3). 1H
NMR (300 MHz, CDCl3, d): 7.41 (d, J = 8.4 Hz, 2H, Ar-
H), 7.34 (d, J = 8.4 Hz, 2H, Ar-H), 6.96 (d, J = 8.7 Hz,
4H, Ar-H), 6.78 (d, J = 8.7 Hz, 2H, Ar-H), 6.71 (d, J =
6.9 Hz, 2H, Ar-H), 6.71 (dd, J = 18.0, 11.9 Hz, 1H,
CH2@CH), 5.75 (d, J = 17.4 Hz, 1H, CH2@CH), 5.49
(br s, 2H, NH), 5.25 (d, J = 11.1 Hz, 1H, CH2@CH),
4.96 (s, 2H, CH2), 4.79 (br s, 2H, CH), 3.73 (s, 3H,
CH3), 1.43 (s, 18H, CH3). 13C NMR (75 MHz, CDCl3,
d): 159.0, 137.5, 136.6, 128.7, 127.9, 126.6, 114.9, 114.0,
69.9, 55.4, 28.6. Anal. Calcd for C34H42N2O6: H, 7.37, C,
71.06, N, 4.87. Found for C34H42N2O6: H, 7.40, C, 71.10,
N, 4.90.
4.3.6. Compound 7d. In the same manner, 0.35 g
(0.58 mmol) of 6 b, 5 mL of DMF, 0.14 mL (0.20 g;
1.16 mmol) of benzyl bromide and 0.48 g (3.48 mmol) of
K2CO3 gave 0.29 g (0.42 mmol) of 7d as a white solid.
Yield 72%. Rf = 0.50 (hexane–EtOAc 3:1). Mp 140–
142 °C. 1H NMR (300 MHz, CDCl3, d): 7.39–7.37 (m,
5H, Ar-H), 7.33 (d, J = 8.1 Hz, 2H, Ar-H), 7.15 (d,
J = 8.1 Hz, 2H, Ar-H), 6.99-6.94 (m, 4H, Ar-H), 6.80 (d,
J = 8.1 Hz, 2H, Ar-H), 6.70 (dd, J = 18.0, 10.0 Hz, 1H,
CH2=CH), 6.70 (d, J = 8.4 Hz, 2H, Ar-H), 5.71 (d,
J = 15.0 Hz, 1H, CH2@CH), 5.51 (br s, 2H, NH), 5.20
(d, J = 9.0 Hz, 1H, CH2@CH), 4.97 (br s, 2H, CH), 3.88
(br s, 2H, CH2), 2.66 (br s, 2H, CH2), 1.77 (br s, 2H,
CH2), 1.44 (s, 18H, CH3). 13C NMR (75 MHz, CDCl3,
d): 142.2, 137.1, 136.9, 135.5, 128.8, 128.2, 127.7, 126.4,
114.9, 113.2, 70.1, 67.9, 35.5, 29.0, 28.6, 28.0. Anal. Calcd
for C43H52N2O6: H, 7.56; C, 74.54; N, 4.04. Found for
C43H52N2O6: H, 7.53, C, 74.52l; N, 4.09.
4.4. Preparation of polymeric chiral 1,2-diamine 9
4.4.1. Compound 9a. An ample tube equipped with a
magnetic stirring bar was charged with 0.1 g (0.17 mmol)
of 7a, 0.16 g (1.57 mmol) of styrene, 0.006 g (0.035 mmol)
of AIBN and 1.3 mL of THF. The ample tube was de-
gassed three times by freeze-thaw in vacuo, sealed off,
and placed in an oil bath (70 °C) and stirred for four days.
The polymer solution obtained was then poured into
100 mL of methanol. The precipitated polymer was col-
lected by filtration, washed with methanol, and dried under
reduced pressure to give 0.193 g (73%) of (R,R)-8a as a
4.3.4. Compound 7b. In the same manner, 0.35 g
(0.62 mmol) of 6a, 5 mL of DMF, 0.15 mL (0.21 g;
1.25 mmol) of benzylbromide and 0.52 g (3.7 5 mmol) of
K2CO3 gave 0.41 g (0.63 mmol) of 7b as a white solid.
Yield >99%. Rf = 0.45 (hexane–EtOAc 3:1). Mp 200–
202 °C. 1H NMR (300 MHz, CDCl3, d): 7.40–7.33 (m,
9H, Ar-H), 6.96 (d, J = 8.1 Hz, 4H, Ar-H), 6.79 (d,
J = 8.7 Hz, 2H, Ar-H), 6.78 (d, J = 9.0 Hz, 2H, Ar-H),
6.71 (dd, J = 18.0, 10.8 Hz, 1H, CH2=CH), 5.75 (d,
1
white solid. H NMR (300 MHz, CDCl3, d): 7.5–6.3 (br,
Ar-H), 5.5 (br, NH), 4.8 (br, CH), 3.7 (br, CH3), 2.1–1.0
(br, CH2, CH). Anal. Calcd for: H, 7.60; C, 84.2; N,
1.85. Found: H, 7.58; C, 84.35; N, 1.80.