Supporting Information
Selective and Reactive Hydration of Nitriles to Amides in Water on the Specific
Surface of Silver Nanoparticles Created Using Silver–Carbon Covalent Bonds
Koji Kawai a, b, Hayato Kawakami, b Takashima Narushima,a Tetsu Yonezawa a
a
Division of Materials Science and Engineering, Facutly of Engineering, Hokkaido
University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido, 060-8628, Japan
b
Miyoshi Oil and Fat Co., Ltd, 4-66-1 Horikiri Katsushika-ku, Tokyo, 124-8510, Japan
Apparatus. NMR: 1H and
13
C NMR studies of compounds were recorded on Bruker
AVANCE III Micro-bay 400MHz spectrometers at room temperature. Chemical shifts
in ppm were referenced to tetramethylsilane (0.00 ppm) as an internal standard. Gas
chromatography(GC) : Gas chromatography was performed on Shimadzu GC-2010 Plus
equipped with a capillary column (GL science, TC-1, 15m) and a FID detector.
Materials. Tetrafluoroboric acid (42 wt% aqueous solution, Wako, Japan),
4-aminobenzoic acid (>99.0%, TCI, Japan), sodium nitrite (>98.5%, Kanto, Japan),
silver nitrate (99.8%, Wako), sodium borohydride (>93.0%, TCI) and polyvinyl
pyrrolidone (PVP, Wako, Mw=40,000) and ethylene glycol (>99.5%, Kanto) were used
without further purification. Deionized (DI) water (<0.1 μS/cm) was used.
Preparation of a water soluble diazonium ligand for silver nanoparticle stabilization.26
As the water soluble ligand for silver nanoparticle stabilization, we have prepared
4–diazoniumcarboxylbenzene fluoroborate. (1). 4-Aminobenzoic acid (50.02 g, 0.365
mol) was dissolved into 42 wt% aqueous solution of hydrogen tetrafluoroborate (HBF4,
152.45 g, 0.729 mol). Into this solution, a 40 wt% aqueous solution of sodium nitrite
(NaNO3, 62.89 g, 0.365 mol) was introduced slowly at 10 – 15 °C for 30 min. After
stirring this mixture for 10 min, diazonium compound (1) was obtained as white solid
by filtration and recrystallization.
HOOC
NH 2 + NaNO 2 + 2HBF4
N N+BF4- + NaBF 4 + 2H2O
HOOC
1
Preparation of water-dispersible silver nanoparticles stabilized by silver-carbon
covalent bond.26
For the nanoparticle preparation, inside scratch-free flasks cleaned
with aqua regia was used for uniform particle preparation. An aqueous solution of silver
nitrate (AgNO3, 0.2592 g, 1.53 mmol) was degassed with nitrogen bubbling for 20 min.
Into this solution, the synthesized diazonium compound 1 (0.3600 g, 1.53 mmol) was
introduced and stirred for 5min. Aqueous sodium tetrahydroborate (NaBH4, 0.0058 g,
1.53 mmol in 45 mL of water) was then added dropwise (for 3 h) into this solution at
room temperature under vigorous stirring and it simultaneously reduced silver nitrate
and 1 to form silver nanoparticles stabilized via silver-carbon bonds. The reaction
solution was kept stirred for 2 h. The nanoparticles were then collected by centrifugal
filtration. Silver nanoparticle (2) stabilized by the corresponding carboxyphenyl group
were obtained by wash with water, and they are dispersed in water. TEM (Hitachi
H-9500) observation of these silver nanoparticles revealed the average diameter of 20.1
nm ± 7.7nm.
HOOC
N N+BF4- +
AgNO 3
HOOC
Ag
2
Preparation of silver nanoparticles stabilized by PVP. Silver nanoparticles stabilized by
PVP were synthesized by following a previous literature.11 An ethylene glycol solution
(30mL) of silver nitrate (AgNO3, 0.5100g, 3.00 mmol) and an ethylene glycol solution
(30mL) of PVP (6.3545g, 45.0mmol) were respectively added dropwise into ethylene
glycol (15mL) at a rate of 0.3 mL/min. After dropping, the reaction solution was
refluxed at 160 °C for 60 min, and cooled to room temperature. The obtained silver
nanoparticles were precipitated with acetone, and washed with ethanol by centrifugation
at several times. These silver nanoparticles were revealed the average diameter of 67.1
nm ± 17.0 nm by TEM (Hitachi H-9500) observation.
Frequency (%)
30
100 nm
20
10
0
0
20
40
60
80
100
120
Diameter (nm)
Figure 1S. TEM i mage and size-distribution histograms o f Ag nanoparticles
stabilized with P VP . The average size and the standard deviation of the particle
size of Ag NP s are 67.1 ± 17.0nm.
Catalytic properties of the prepared silver nanoparticles. Catalytic ability of silver
nanoparticles for nitrile hydration was investigated in this study. Hydration reactions of
nitriles were carried out with nitrile (1 mmol), water dispersible silver nanoparticles
(0.03 mmol of Ag, 3 mol% of nitrile) in water (7 cm3). The obtained products were
analyzed by gas chromatography (Shimadzu GC-2010Plus) and 1H-NMR spectra
(Bruker AVANCE III Micro-bay 400 MHz spectrometer).
Product identification. The yields of products were determined by GC and / or 1H-NMR.
GC analysis was operated under the following conditions. carrier gas: He (60 kPa),
column: GL science Capillary Column TC-1 15m, oven temperature program: from
40 °C, hold for 3 min, 10 °C/min up to 200 °C, injection and detection temperature:
150 °C and 200 °C.
NMR spectrum of products:
Benzamide (Table 1, Entry 1)
1
H NMR (400MHz, d6-DMSO) δ 8.08 (bs, 1H), 7.79 (d, J = 7.03 Hz, 2H), 7.53 (t, J =
7.47 Hz, 1H), 7.44(t, J = 7.65 Hz, 2H), 7.27 (bs, 1H); 13C NMR (100MHz, d6-DMSO) δ
170.11, 132.86, 132.03, 128.54, 127.22.
Nicotinamide (Table 1, Entry 2)
1
H NMR (400MHz, d6-DMSO) δ 8.97 (d, J = 1.51 Hz, 1H), 8.68 (d, J = 3.26 Hz, 1H),
8.25 (bs, 1H), 8.18(d, J = 8.03 Hz, 1H), 7.59 (bs, 1H), 7.51 (t, J = 3.14 Hz, 1H);
13
C
NMR (100MHz, d6-DMSO) δ 166.95, 151.87, 148.32, 135.38, 129.49, 123.64.
4-Chlorobenzamide (Table 1, Entry 3)
1
H NMR (400MHz, d6-DMSO) δ 8.13 (bs, 1H), 7.81 (d, J = 8.78 Hz, 2H), 7.49 (d, J =
8.66 Hz, 2H), 7.38(bs, 1H); 13C NMR (100MHz, d6-DMSO) δ 168.17, 136.58, 132.23,
129.25, 128.46.
4-Methoxybenzamide (Table 1, Entry 4, 5)
1
H NMR (400MHz, d6-DMSO) δ 8.01 (bs, 2H), 7.84 (d, J = 8.91 Hz, 2H), 7.05 (d, J =
8.91 Hz, 2H), 3.83(s, 3H);
C NMR (100MHz, d6-DMSO) δ 169.21, 161.86, 129.38,
13
125.32, 113.63, 55.24.
4-Methylbenzamide (Table 1, Entry 6)
1
H NMR (400MHz, d6-DMSO) δ 7.99 (bs, 1H), 7.65 (d, J = 8.28 Hz, 2H), 7.25 (d, J =
7.97 Hz, 2H), 7.12 (bs, 1H), 2.29(s, 3H);
13
C NMR (100MHz, d6-DMSO) δ 169.97,
142.35, 129.92, 129.00, 127.28, 20.60.
n-Octanamide (Table 1, Entry 10)
1
H NMR (400MHz, CD3OD) δ 2.23 (t, J = 7.53 Hz, 2H), 1.64 (q, J = 7.09 Hz, 2H), 1.31
(m, 8H), 0.90 (t, J = 6.84 Hz, 3H);
13
C NMR (100MHz, CD3OD) δ
175.64, 36.68,
32.73, 30.06, 29.94, 26.88, 22.01, 14.63.
Acrylamide (Table 1, Entry 11)
1
H NMR (400MHz, d6-DMSO) δ 6.23 (d, J = 7.47 Hz, 1H), 6.17 (d, J = 15.12 Hz, 1H),
5.75 (d, J = 7.84 Hz, 1H); 13C NMR (100MHz, d6-DMSO) δ 168.21, 130.45, 127.37.
Chloroacetamide (Table 1, Entry 13, 14)
1
H NMR (400MHz, d6-DMSO) δ 4.06 (s, 2H);
172.21, 61.24.
13
C NMR (100MHz, d6-DMSO) δ