Y. Liu et al. / Tetrahedron xxx (2018) 1e13
3
concentrated to give a crude product that was purified by column
chromatography (CH2Cl2/CH3OH ¼ 200/1) to give 17 as brown solid.
Yield: 2.03 g, 78%. 1H NMR (400 MHz, CDCl3, 25 ꢀC, TMS), dppm: 7.65
(s, 2H, 2 ꢂ C]CH of triazole), 7.62 (s, 1H, C]CH of triazole), 7.30 (s,
2H, ph), 6.72 (s, 2H, ph), 5.25 (s, 4H, 2 ꢂ pheOCH2etriazole), 5.21 (s,
2H, pheOCH2etriazole), 5.18 (s, 2H, COOCH2), 5.12 and 5.09 (ds,
4Hþ2H, 3 ꢂ N]NeNeCH2), 4.28, (t, J ¼ 3.4 Hz, 4H, 2 ꢂ sub. Cp),
4.23e4.16 (m, 29H, 3 ꢂ ph-OCH2, 4 ꢂ sub. Cp and 3 ꢂ free Cp),
3.87e3.51 (m, 30H, 3 ꢂ CH2OCH2CH2OCH2CH2), 3.36 and 3.36 (ds,
9H, 3 ꢂ OCH3). 13C NMR (100 MHz, CDCl3, 25 ꢀC, TMS), dppm: 1152.4
(COO), 152.2 (ph), 144.4 (ph), 143.8 and 143.7 (C of triazole), 142.7
(ph), 137.5 (ph), 132.2 (ph), 124.8 (ph), 123.2 and 122.8 (C of tri-
azole), 109.1 (ph), 106.2 (ph), 61.3 (HOCH2), 81.4, 81.0, 72.5, 71.9,
70.8, 70.7, 70.6, 69.6, 69.0, 68.9, 66.6 and 66.3 (CH2O and Cp), 63.1
chromatography (CH2Cl2/methanol ¼ 200/1) to give 19 as brown
oil. Yield: 2.93 g, 83%. 1H NMR (400 MHz, CDCl3, 25 ꢀC, TMS), dppm
:
7.91 (s, 2H, 2 ꢂ C]CH of triazole), 7.89 (s, 1H, C]CH of triazole),
7.32 (s, 2H, ph), 6.83 (s, 2H, ph), 6.48 (t, J ¼ 10.9 Hz, 1H, NHCO), 6.42
(t, J ¼ 10.5 Hz, 2H, 2 ꢂ NHCO), 5.24 (s, 2H, ph-OCH2-triazole), 5.20
(s, 4H, 2 ꢂ ph-OCH2-triazole), 5.16 (s, 2H, COOCH2), 4.70e4.68 (m,
6H, 3 ꢂ sub. Cp), 4.52e4.47 (m, 6H, 3 ꢂ N]NeNeCH2), 4.29 (t,
J ¼ 3.7 Hz, 6H, 3 ꢂ sub. Cp), 4.23e4.16 (m, 21H, 3 ꢂ ph-OCH2 and
3 ꢂ free Cp), 3.87e3.51 (m, 72H, 3 ꢂ (OCH2CH2)2OCH2 and
3 ꢂ (CH2OCH2)3CH2), 3.36 and 3.36 (ds, 9H, 3 ꢂ OCH3). 13C NMR
(100 MHz, CDCl3, 25 ꢀC, TMS), dppm: 170.4 (NHCO), 152.6 (COO),
152.4 (ph), 143.9, 143.6 (C of triazole), 137.7 (ph), 132.5 (ph), 124.8
and 124.5 (C of triazole), 109.1 (ph), 108.2 (ph), 76.3 (Cp) 72.5, 72.0,
70.8, 70.7 (OCH2), 70.5, 70.4, 70.2, 70.1, 70.0 (OCH2), 69.8, 69.6, 69.3,
69.0, 66.2 (Cp), 63.1 (COOCH2) 50.2 (CH2), 50.0 (CH2), 39.3
(CH2NHCO). MS (ESI m/z), calcd. for C101H138Fe3N12O29: 2151.77;
(COOCH2),
59.0
(OCH3),
50.1
(OCH2-triazole),
49.9
(triazoleeCH2eFc). MS (ESI m/z), calcd. for C77H93Fe3N9O17
:
1584.15; found: 1607.46 (M þNaþ). Selected IR (KBr, cmꢁ1): 3440
found: 718.26 ((M
þ
Hþ)/3), 739.91 (M/3
þ
Naþ), 1076.89
(nOH), 2876
(nCH2), 1713
(
dC]O), 1590, 1500, 1431
(nC]C of
((M þ Hþ)/2), 1087.88 ((M þ Naþ)/2), 1098.97 (M/2 þ Naþ). Selected
IR (KBr, cmꢁ1): 3423 (nOH), 2874 (nCH2), 1713 (dC]O), 1592, 1540,
1431 (nC]C of benzene), 1379, 1331, 1299(nC-N), 1204, 1107(nC-O-C),
824 (nFeII).
benzene), 1330(nC-N), 1206 (nph-O-C), 1106, 1050, 1001, 823(nFeII).
Synthesis of 18: 10 (5.25 g, 12.2 mmol, 3.3 equiv) and 13 (1.0 g,
3.7 mmol, 1.0 equiv) were dissolved in 80 ml of tetrahydrofuran
(THF). CuSO4$5H2O (3.05 g, 12.2 mmol, 3.3 equiv) aqueous solution
(40 ml) was added into the obtained reaction mixture, followed by
the dropwise addition of a freshly prepared sodium ascorbate
(NaAsc, 4.84 g, 24.4 mmol, 6.6 equiv) aqueous solution (40 ml) to
obtain a THF/water in a ratio of 1:1. The reaction mixture was
stirred for 72 h at r. t. under N2 atmosphere, and then vacuumed to
remove THF. The residue was dissolved in CH2Cl2, (80 ml) and
aqueous ammonia (80 ml), and stirred for 30 min to remove the
copper ions trapped inside the targeted compound as
[Cu(NH3)2(H2O)2]2þ. The organic layer was collected, dried by
anhydrous Na2SO4, and evaporated under reduced pressure. Puri-
fication was conducted by column chromatography with CH2Cl2/
methanol (1%/20%) as eluent to provide 18 as orange-yellow oil.
Yield: 4.62 g, 80%. 1H NMR (400 MHz, CDCl3, 25 ꢀC, TMS), dppm: 7.90
(s, 2H, 2 ꢂ C]CH of triazole), 7.86 (s, 1H, C]CH of triazole), 6.73 (s,
2H, ph), 6.59 (t, J ¼ 10.8, 1H, NHCO), 6.51 (t, J ¼ 10.8, 2H, 2 ꢂ NHCO),
5.17 (s, 6H, 3 ꢂ ph-OCH2), 4.72e4.69 (m, 6H, 3 ꢂ sub. Cp), 4.60 (s,
2H, HOCH2), 4.53e4.46 (m, 6H, 3 ꢂ N]NeNeCH2), 4.30 (t, J ¼ 3.8,
6H, 3 ꢂ sub. Cp), 4.17 (s, 15H, 5 ꢂ free Cp), 3.86e3.80 (m, 6H,
Synthesis of AuNPs-1: 19 (4.5 mg, 2.1 ꢂ 10ꢁ3 mmol, 2 equiv)
and NaBH4 (0.24 mg, 6.3 ꢂ 10ꢁ3 mmol, 6 equiv) were dissolved in
methanol (6 ml) in
a Schlenk flask, and HAuCl4 (0.34 mg,
1 ꢂ 10ꢁ3 mmol, 1 equiv) dissolved in water (1.5 ml) was then
injected dropwise into the above Schlenk flask and further stirred
for 2 h at 30 ꢀC under N2 atmosphere to yield AuNPs-1, and the
color changed immediately from light-yellow to pink. The obtained
AuNPs-1 were purified before TEM analysis by dialysis (molecular
weight cut off (MWCO) ¼ 3500 g molꢁ1) against a large volume of
water.
Synthesis of AuNPs-2: HAuCl4 (0.34 mg, 1 ꢂ 10ꢁ3 mmol, 1
equiv) dissolved in water (1.5 ml) was injected dropwise into a
vigorously stirred methanol solution (5 ml) of 19 (9.0 mg,
4.2 ꢂ 10ꢁ3 mmol, 4 equiv) in a Schlenk flask, and further stirred for
30 h at 30 ꢀC under N2 atmosphere. Then NaBH4 (0.24 mg,
6.3 ꢂ 10ꢁ3 mmol, 6 equiv) in methanol (1 ml) was injected drop-
wise into the above-mentioned solution in a Schlenk flask. The
obtained mixture was stirred for 2 h at 30 ꢀC under N2 atmosphere
to yield AuNPs-2, and the color changed immediately from light-
yellow to purple. The obtained AuNPs-2 were purified by dialysis
(MWCO ¼ 3500 g molꢁ1) against a large volume of water.
Synthesis of AuNPs-3: HAuCl4 (0.16 mg, 4.8 ꢂ 10-4 mmol, 1
equiv) dissolved in water (0.71 ml) was injected dropwise into a
vigorously stirred methanol solution (5 ml) of 17 (1.5 mg,
9.5 ꢂ 10ꢁ4 mmol, 2 equiv) in a Schlenk flask, and further stirred
overnight at 30 ꢀC under N2 atmosphere. The color changed slowly
from light-yellow to deep purple. The obtained AuNPs-3 were
purified by dialysis (MWCO ¼ 3500 g molꢁ1) against a large volume
of water before analysis.
3 ꢂ N]NeNeCH2CH2),
3.59e3.48
(m,
36,
3 ꢂ OCH2(-
13
CH2OCH2)2CH2N). C NMR (100 MHz, CDCl3, 25 ꢀC, TMS), dppm
:
170.6 (NHCO), 152.2 (ph), 144.4 and 143.7 (C of triazole), 136.3 (ph),
124.7 (ph),124.6 (C of triazole),106.2 (ph), 70.4, 70.3, 70.2, 70.1, 70.0
(HOCH2), 69.4, 69.3, 68.3, 66.3, 64.7, 62.9 (Cp), 50.2 (CH2), 50.0
(CH2), 39.3 (CH2NHCO). MS (ESI m/z), calcd. for C73H92Fe3N12O16
:
1561.12; found: 781.24 (Mþ/2), 792.23 ((M þ Naþ)/2), 800.22
((M þ Kþ)/2), 803.73(M/2 þ Naþ), 1584.47 (M þ Naþ). Selected IR
(KBr, cmꢁ1): 3346 (nOH), 2872 (nCH2), 1633 (dC]O), 1539, 1504, 1438
(
(
nC]C of benzene), 1379, 1351, 1301(nC-N), 1227, 1106 ((nC-O-C), 824
nFeII).
Synthesis of AgNPs-1: 19 (4.5 mg, 2.1 ꢂ 10ꢁ3 mmol,1 equiv) and
Synthesis of 19: Oxalyl dichloride (1.04 g, 8.21 mmol, 5 equiv)
NaBH4 (0.238 mg, 6.3 ꢂ 10ꢁ3 mmol, 3 equiv) were dissolved in
was added dropwise at 0 ꢀC under N2 atmosphere to a solution of 15
(1.0 g, 1.64 mmol, 1 equiv) in dry CH2Cl2 (30 ml). The mixture was
stirred overnight at r. t. under N2 atmosphere, and the mixture was
concentrated to give a crude product 16, which was used in the next
step without further purification. Then, to a mixture of 18 (2.56 g,
1.64 mmol, 1 equiv) and Et3N (0.83 g, 8.21 mmol, 5 equiv) in dry
CH2Cl2 (30 ml) was added the crude 16 in dry CH2Cl2 (20 ml)
dropwise at 0 ꢀC under N2 atmosphere. The mixture was stirred at r.
t. overnight. Distilled water (50 ml) was then added into the
mixture, and the organic layer was separated. The aqueous layer
was extracted with CH2Cl2 (50 ml ꢂ 3). The organic layers were
combined, washed with brine, dried over anhydrous Na2SO4 and
concentrated to give a crude product that was purified by column
methanol (5 ml) in a Schlenk flask, and AgNO3 (0.35 mg,
2.1 ꢂ 10ꢁ3 mmol, 1 equiv) aqueous solution (0.36 ml) was then
injected dropwise into the flask under N2 atmosphere with
vigorous stirring. The obtained solution was further stirred for
2 h at 30 ꢀC under N2 atmosphere, and the color changed from
light-yellow to brownish red. Dialysis (MWCO ¼ 3500 g molꢁ1) was
conducted against a large volume of distilled water before the TEM
analysis of the produced AgNPs-1.
Synthesis of AgNPs-2: AgNO3 (0.35 mg, 2.1 ꢂ 10ꢁ3 mmol, 1
equiv) was dissolved in distilled water (0.36 ml), and injected
dropwise into a vigorously stirred methanol solution (5 ml) of 19
(4.5 mg, 2.1 ꢂ 10ꢁ3 mmol, 1 equiv) in a Schlenk flask. The obtained
mixture was stirred overnight at 30 ꢀC under N2 atmosphere. Then
Please cite this article in press as: Y. Liu, et al., Ferrocenyl Janus mixed-dendron stars and their stabilization of Au and Ag nanoparticles,