3
28
C.-Y. Li et al. / Inorganica Chimica Acta 435 (2015) 327–334
H
B
70.9 (NCH
(CH, pyrazole), 130.9, 140.8 (Cipso, pyrazole), 141.1, 148.2. Anal.
Calc. for C40 54CuN10PF (CH CN)0.3: C, 54.44; H, 6.18; N, 16.11.
2 3
N), 106.8 (CH, pyrazole), 116.6 (CH CN), 124.9, 128.7
R
R
R'
N
N
N
N
N
N
N
N
H
6
3
NR
2
N
N
N
R
n
N
O
Found: C, 54.77; H, 6.02; N, 15.11.
R
R
R
R
R
R
R
2.2.3. Synthesis of [Cu(LN3)]I (3)
R
N
O
Similar procedure as discussed for synthesizing 1 was adopted.
Ligand LN3 (0.17 g, 0.52 mmol) and CuI (0.10 g, 0.52 mmol) were
used and the resulting pale blue solid was recrystallized from an
X
n
N
N
N
N
N
N
n
N
Scheme 1. Neutral and mono-anionic chelated nitrogen donor atoms ligands.
acetonitrile solution to generate the white solid (0.44 g, 81% yield).
1
3 2 2
H NMR (CDCl ): 0.90 (d, 12H, CHMe ), 2.60 (m, 2H, CHMe ), 5.79
(
s, 4H, NCH
2
N), 6.09 (t, 2H, pyrazole CH), 7.06–7.27 (m, 5H, phenyl
We expand a series of copper(I) compounds coupled with
13
1
and pyrazole CH), 7.97 (d, 2H, pyrazole CH). C{ H} NMR (CDCl
3
):
N), 105.0 (CH, pyrazole),
24.8, 128.4 (CH, pyrazole), 130.1, 141.3 (Cipso, pyrazole), 142.8,
48.6. Anal. Calc. for C20 CuI: C, 45.50; H, 5.16; N, 13.27.
ArN[CH
2
(C
3
H
3
N
2
)]
2
(Ar = 2,6-diisopropylphenyl) (LN3) and use
and pyrazine. Compounds 1–
2
1
1
2 2 2
4.8 (CHMe ), 28.3 (CHMe ), 71.7 (NCH
these derivatives to react with PPh
3
13
6
were characterized by 1H and C NMR spectroscopy and most
27 5
H N
of them were further signalized by single crystal X-ray diffractom-
etry. The catalytic ability of synthesized copper compounds was
investigated with Sonogashira type C–C coupling reaction as well.
Found: C, 45.64.; H, 5.23; N, 13.21.
2
3 6
.2.4. Synthesis of [Cu(LN3)(PPh )]PF (4)
A 100 mL Schlenk flask charged with 1 (1.20 g, 1.91 mmol) and
0 mL methylene chloride was added dropwise with a methylene
2
. Experimental section
2
3
chloride (20 mL) solution of PPh (0.50 g, 1.91 mmol) at room tem-
perature. The resulting solution was stirred for 12 h and dried
under vacuum to yield white solid. The solid was recrystallized
2
.1. Materials and physical measurements
All the reactions were performed using standard Schlenk tech-
from a toluene/methylene chloride solution at À20 °C to generate
1
niques under an atmosphere of high purity nitrogen or in glove
box. Cu(CH CN) PF , CuI, bis(2-methoxyethyl)amine, formalde-
hyde and pyrazole (Aldrich) were obtained commercially and used
as received. The ArN[CH (C )] (Ar = 2,6-diisopropylphenyl)
LN3) was synthesized according to published literature [23]. All
colorless crystals of 4. (1.42 g, 92% yield). H NMR (CDCl
(
3
): 0.96
N), 6.25 (t,
H, pyrazole CH), 7.09–7.48 (m, 21H, phenyl and pyrazole CH).
3
4
6
3 2 2
d, 12H, CH ), 2.59 (m, 2H, CHMe ), 5.60 (s, 4H, NCH
2
1
3
1
2
H
3 3
N
2
2
3 2 2 2
C{ H} NMR (CDCl ): 24.8 (CHMe ), 28.5 (CHMe ), 71.9 (NCH N),
(
1
1
1
5
06.9 (CH, pyrazole), 125.0, 125.2, 128.2, 128.9, 129.0, 129.4,
30.9, 131.0, 132.2, 133.5, 137.8, 140.5 (Cipso, pyrazole), 143.3,
solvents were distilled and stored in solvent reservoir, which con-
1
tained 4 Å molecular sieves and were purged with nitrogen. H and
5 2 6 6 5 3
48.2. Anal. Calc. for C38H42CuN P F (C H CH )0.9: C, 59.70; H,
1
3
C NMR spectra were recorded on a Bruker Avance 300 spectrom-
.56; N, 7.86. Found: C, 59.62; H, 5.46; N, 7.72.
1
13
eter. Chemical shifts for H and C spectra were recorded in ppm
relative to the residual protons of CDCl (d 7.24, 77.0). Elemental
analyses were performed on a Heraeus CHN-OS Rapid Elemental
Analyzer at the Instrument Center of the NCHU.
3
2
.2.5. Synthesis of [Cu(LN3)(PPh
Similar procedure as mentioned for synthesizing 4 were
adopted except that two equivalents of PPh (1.00 g, 3.82 mmol)
3 2 6
) ]PF (5)
3
was used. Complex 5 was obtained from a toluene/methylene chlo-
1
2
2
2
.2. Synthesis of the complexes
ride solution at À20 °C (1.80 g, 88% yield). H NMR (CDCl ): 1.04 (d,
3
1
2 2 2
2H, CHMe ), 2.13 (m, 2H, CHMe ), 4.89 (s, 4H, NCH N), 6.47 (t, 2H,
13
1
.2.1. Synthesis of [Cu(LN3)(CH
A 100 mL Schlenk flask charged with [Cu(CH
.63 mmol) and 30 mL acetonitrile was added dropwise an ace-
3
CN)
2
]PF
6
(1)
pyrazole CH), 7.04–7.45 (m, 36H, phenyl and pyrazole CH). C{ H}
NMR (CDCl ): 25.0 (CHMe ), 28.5 (CHMe ), 66.1 (NCH N), 107.8
3 4 6
CN) ]PF (1.0 g,
3
2
2
2
(CH, pyrazole), 124.8, 128.4, 129.0, 130.4, 131.6, 132.0, 133.3,
141.8, 142.4, 147.0. Anal. Calc. for C56H57CuN P F : C, 62.83; H,
tonitrile solution (30 mL) of LN3 (0.89 g, 2.63 mmol) at 0 °C. The
resulting solution was stirred for 12 h and filtered through Celite.
The filtrate was vacuum dried and the solid was recrystallized from
5
3 6
5.37; N, 6.54. Found: C, 62.86; H, 5.31; N, 6.37.
a toluene/acetonitrile mix solvent to yield white crystals of 1
2.2.6. Synthesis of {[Cu(LN3)(pyrazine)] (PF ) } (6)
2
6 2 n
1
(
3
1.49 g, 90% yield). H NMR (CDCl ): 0.89 (d, 12H, CHMe
2
), 2.20 (s,
A Schleck flask charged with 1 (0.40 g, 0.64 mmol) and pyrazine
(0.051 g, 0.64 mmol) and 30 mL of THF was stirred at room tem-
perature for 12 h. The resulting solution was filtered through
Celite and filtrate was concentrated to small volume and stored
at À20 °C to afford orange crystals of product (0.10 g, 22% yield).
6
2
7
2
1
H, CH
3
CN), 2.60 (m, 2H, CHMe
2
), 5.49 (s, 4H, NCH N), 6.29 (t,
2
H, pyrazole CH), 7.05–7.23 (m, 5H, phenyl CH and pyrazole CH),
.74 (d, 2H, pyrazole CH). 13C{ H} NMR (CDCl
4.6 (CHMe ), 28.4 (CHMe ), 73.1 (NCH N), 106.3 (CH, pyrazole),
17.0 (CH CN), 125.0 (CH, phenyl), 128.8 (CH, pyrazole), 131.4
1
3 3
): 2.1 (CH CN),
2
2
2
1
6
3
2 2
H NMR (d -DMSO): 0.91 (d, 12H, CHMe ), 2.68 (m, 2H, CHMe ),
(
CH, phenyl), 140.5 (Cipso, pyrazole), 142.4 (Cipso, phenyl), 148.3
ipso, phenyl). Anal. Calc. for C24 33CuN PF : C, 45.90; H, 5.30; N,
5.60. Found: C, 45.40; H, 5.28; N, 15.70.
5.63 (s, 4H, NCH N), 6.40 (t, 2H, pyrazole CH), 7.15–7.31 (m, 6H,
2
(C
H
7
6
phenyl CH), 7.78 (d, 2H, pyrazole CH), 7.89 (d, 2H, pyrazole CH),
1
3
1
6
1
8.73 (d, 4H, pyrazine CH).
C{ H} NMR (d -DMSO): 24.4
N), 105.8 (CH, pyrazole),
(
CHMe ), 27.9 (CHMe ), 72.1 (NCH
2
2
2
2
.2.2. Synthesis of [Cu(LN3)
Similar procedure as described for synthesizing 1 was adopted.
Ligand LN3 (3.55 g, 10.52 mmol) and [Cu(CH CN) ]PF (2.00 g,
.26 mmol) were used and the resulting solid was recrystallized
from a heptane and acetonitrile mix-solvent to generate the color-
2
]PF
6
(2)
124.7, 128.3 (CH, pyrazole), 132.4, 141.3, 141.4, 145.5, 148.1.
3
4
6
2.3. General procedure for C–C bond formation reaction
5
A glass tube was charged with cesium carbonate (1.0 mmol)
and catalyst (5 mol% with respect to the phenylacetylene) and
was sealed tightly with rubber septum. The sealed tube was taken
out of the glove box and phenylacetylene (2.5 mmol), aryl halide
(2.0 mmol) and toluene (15.0 mL) were injected into the tube
1
less solid (4.60 g, 94% yield). H NMR (CDCl
3
): 1.00 (d, 24H, CHMe
), 5.55 (s, 8H, NCH N), 6.36 (t,
H, pyrazole CH), 7.11–7.47 (14H, phenyl and pyrazole CH).
2
),
1
4
.99 (s, CH
3
CN), 2.68 (m, 4H, CHMe
2
2
1
3
1
3 3 2 2
C{ H} NMR (CDCl ): 1.7 (CH CN), 24.8 (CHMe ), 28.4 (CHMe ),