Synthesis, characterization, and highly selective ethylene dimerization to 1-butene of [O-NX]Ni(II) complexes

Article abstract of DOI:10.1002/cjoc.201100443

A series of nickel(II) complexes have been synthesized and characterized. Molecular structure analysis exhibits that a square planar geometry around nickel is adopted. Upon activation with MAO, these nickel(II) complexes are efficient in catalyzing the et

Full text of DOI:10.1002/cjoc.201100443

FULL PAPER
DOI: 10.1002/cjoc.201100443
Synthesis, Characterization, and Highly Selective Ethylene
Dimerization to 1-Butene of [O－NX]Ni(II) Complexes†
Xu, Chongjiea(许崇杰)
Shen, Qia(沈琪)
Sun, Xiuli*,b(孙秀丽)
Tang, Yongb(唐勇)
a School of Chemistry and Chemical Engineering, Suzhou University, Suzhou 215123, China
b State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, 345 Lingling Lu,
Shanghai 200032, China
A series of nickel(II) complexes have been synthesized and characterized. Molecular structure analysis exhibits
that a square planar geometry around nickel is adopted. Upon activation with MAO, these nickel(II) complexes are
efficient in catalyzing the ethylene dimerization, providing 1-butene with an activity of up to 1.4×107
g/(mol•h•atm). The heteroatoms of the sidearm in the complexes were proved to have great impact on the activity
and selectivity of 1-butene.
Keywords nickel complexes, ethylene dimerization, 1-butene, selectivity
Introduction
been interested in the olefin coordination polymeriza-
tion and oligomerization, and a series of new metal
complexes were applied successfully in ethylene (co)po-
lymerization,[14] in which the nickel complexes derived
from N-[(1H-pyrrol-2-yl)methylene]-2-(diphenylphos-
phino)benzenamine were found active to polymerize
the norbornene.[15] Recently, we designed a kind of
nickel complexes derived from tridentate ligands [ONS],
which are highly active [up to 14.25 × 106 g/
(mol(Ni)•h•atm)] in catalyzing the ethylene dimeriza-
tion to provid 1-butene with up to ＞99% selectivity. In
this paper we wish to report the results.
Organonickel complexes have attracted much atten-
tion in the filed of olefin polymerization and oligomeri-
zation.[1] And tremendous advances were achieved in
both industry and academic field.[2] For example, SHOP
catalyst, developed by Keim et al., can efficiently con-
vert ethylene into value added α-olefins, which has be-
come one of the largest applications of homogeneous
catalysis by a transition metal.[3-6] However, of all the
nickel complexes developed, we noticed that bidentate
ligands were involved in most cases, probably because
of either a square planar geometry or a tetrahedral ge-
ometry around nickel being considered suitable to meet
the requirement of the olefin coordination polymeriza-
tion.[7-10] Though a few examples of nickel complexes
based on tridentate ligands have been reported for this
purpose,[11-13] either low activity or low selectivity to-
wards α-olefin was always observed. Recently, Braun-
stein et al. described a bis(oxazolinyl)phenyl phos-
phonite nickel complex used to promote oligomerization
of ethylene with an activity up to 1.1 × 105
g/(mol(Ni)•h•atm) in the presence of AlEtCl2 with the
selectivity for α-butene being up to 21%.[11] Casagrande
et al. documented that tridentate pyrazolyl nickel com-
plexes were efficient catalysts for the ethylene dimeri-
zation.[12] Very rencently, by employing the abovemen-
tioned tridentate pyrazolyl nickel complexes, they ob-
tained butenes in an activity of 5.3 × 104
g/(mol(Ni)•h•atm) along with 81% selectivity for
1-butene under the optimized conditions.[12b] We have
Experimental
All manipulations of air- and/or moisture-sensitive
compounds were performed under nitrogen atmosphere
1
using standard Schlenk techniques. H NMR and 13C
NMR spectra were recorded on a Varian XL-300 MHz
or 400 MHz spectrometer with TMS as the internal
standard. Mass spectra were obtained using an
HP5959A spectrometer. IR spectra were recorded using
an Nicolet AV-360 spectrometer. Elemental analysis
was performed by the Analytical Laboratory of Shang-
hai Institute of Organic Chemistry, Chinese Acadamy of
Sciences. X-ray crystallographic data were collected
using a Bruker AXSD8 X-Ray diffractometer. Toluene,
THF, hexane and dichloromethane were treated with
solvent purification MB SPS-800 for MBRAUN glove
box systems prior to use. Methylaluminoxane (MAO)
was purchased from Akzo Chemical as an 1.5 mol/L
*
E-mail: xlsun@sioc.ac.cn; Tel.: 0086-021-54925078; Fax: 0086-021-54925078
Received September 30, 2011; accepted January 9, 2012; published online May 7, 2012.
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cjoc.201100443 or from the author.
† Dedicated to Professor Weiyuan Huang on the occasion of his 90th birthday.
Chin. J. Chem. 2012, 30, 1105—1113
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
1105

Xu et al.
FULL PAPER
toluene solution. Polymerization-grade ethylene was
purified before use. Gas chromatographic analyses were
performed on an Agilent 7890A gas chromatograph us-
ing an HP Pona column (50 m, 0.2 mm diameter, 0.5
μm film thickness).
found C 77.57, H 7.52, N 9.54.
(Z)-3-(2-(Diphenylphosphino)ethylamino)-1,3-
diphenylprop-2-en-1-one (L10) The same procedure
1
as that for L6. Pale-yellow solid (47%). H NMR (300
MHz, CDCl3) δ: (s, 1H, NH), 7.89—7.86 (m, 2H),
7.40—7.25 (m, 18H), 5.74 (s, 1H, C＝CH), 3.34—3.28
(m, 2H, N-CH2), 2.32—2.27 (m, 2H, P-CH2); 13C NMR
(75 MHz, CDCl3) δ: 188.2, 166.2, 140.0, 137.2, 137.0,
135.1, 132.4, 132.2, 130.6, 129.3, 128.6, 128.4, 128.3,
128.0, 127.4, 126.9, 93.6, 41.7, 41.3, 30.2, 30.1; 31P
NMR (121 MHz, CDCl3) δ: －20.78; IR (KBr) ν: 3051,
2932, 2865, 1594, 1566, 1408, 1289, 817, 785, 753, 747,
Synthesis of the ligands
[17]
Ligands L1—L5,[14f] L7[14f] and NiPhCl(PPh3)2
were prepared according to the reported procedure.
(Z)-3-(2-(Cyclohexylthio)ethylamino)-1,3-diphen-
ylprop-2-en-1-one (L6) To a solution of 1,3-diphe-
nylpropane-1,3-dione (11.62 g, 51.8 mmol) and 2-(cyclo-
hexylthio)ethanamine (8.24 g, 51.8 mmol) in toluene
(60 mL) was added 4-methylbenzenesulfonic acid hy-
drate (0.78 g, 4.1 mmol) at room temperature. The flask
was equipped with a water separator. After refluxing for
1 d, the solvent was removed under reduced pressure
and the residue was purified by column chromatography
on silica gel to give product as yellow solid 8.3 g. Yield
46%. 1H NMR (300 MHz, CDCl3) δ: 11.45 (s, 1H), 7.89
(d, J＝6.3 Hz, 2H), 7.44—7.38 (m, 8H), 5.78 (s, 1H,
C＝CH), 3.38 (q, J＝7.1 Hz, 2H), 2.63 (t, J＝7.2 Hz,
2H), 2.45 (brs, 1H, S-CH), 1.81—1.57 (m, 5H), 1.25—
1.17 (m, 5H); 13C NMR (75 MHz, CDCl3) δ: 88.5,
166.3, 140.0, 135.4, 130.7, 129.4, 128.5, 128.1, 127.6,
127.0, 93.8, 44.8, 43.3, 33.5, 30.5, 26.0, 25.6; IR (KBr)
ν: 3055, 2925, 2848, 1605, 1582, 1553, 1339, 782, 765,
－
＋
1
738, 695 cm ; MS (EI) m/z: 435 (M ), 330 (M－
PhCO). HRMS (EI) calcd for C29H26NOP (M ＋
)
435.1752, found 435.1752. Anal. calcd for C29H26NOP:
C 79.98, H 6.02, N 3.22; found C 79.95, H 6.24, N 3.02.
(Z)-3-(2-Phenoxyethylamino)-1,3-diphenylprop-2-
en-1-one (L11) The same procedure as that for L6.
Yellow oil (60%). 1H NMR (300 MHz, CDCl3) δ: 11.52
(s, 1H, NH), 7.90—7.87 (m, 2H), 7.43—7.36 (m, 8H),
7.29—7.23 (m, 2H), 6.97—6.86 (m, 3H), 5.80 (s, 1H,
C＝CH), 4.03 (t, J＝6.3 Hz, 2H), 3.61 (q, J＝5.9 Hz,
2H, O-CH2); 13C NMR (75 MHz, CDCl3) δ: 188.5,
166.5, 158.1, 140.0, 135.2, 130.6, 129.4, 129.3, 128.4,
128.0, 127.7, 126.9, 120.9, 114.4, 93.9, 66.8, 43.7; IR
(KBr) ν: 3060, 2930, 1595, 1569, 1332, 1243, 1060, 813,
－
＋
1
777, 751, 692 cm ; MS (EI) m/z: 343 (M ), 250 (M－
PhO). HRMS (EI) calcd for C23H21NO2 (M＋) 343.1575,
found 343.1572. Anal. calcd for C23H21NO2: C 80.44, H
6.16, N 4.08; found C 80.45, H 6.07, N 4.17.
－
＋
1
746, 690 cm ; MS (EI) m/z: 365 (M ), 236 (M－
CH2SCy). HRMS (EI) calcd for C23H27NOS (M＋ )
365.1813, found 365.1813. Anal. calcd for C23H27NOS:
C 75.57, H 7.45, N 3.83; found C 75.68, H 7.40, N 3.85.
(Z)-5,5,5-Trifluoro-4-(2-(isopropylthio)ethylami-
no)pent-3-en-2-one (L8) The same procedure as that
(Z)-1,3-Diphenyl-3-(pyridin-2-ylmethylamino)-
prop-2-en-1-one (L12) The same procedure as that
for L6. Yellow solid (60%). 1H NMR (300 MHz, CDCl3)
δ: (s, 1H, NH), 8.57 (d, J＝4.2 Hz, 1H ); 7.93 (d, J＝5.4
Hz, 2H), 7.70—7.66 (m, 1H), 7.43—7.16 (m, 10H),
5.89 (s, 1H, C＝CH), 4.57 (d, J＝5.4 Hz, 2H); 13C
NMR (75 MHz, CDCl3) δ: 188.4, 166.2, 157.2, 149.1,
139.7, 136.5, 135.0, 130.5, 129.3, 128.3, 127.9, 127.3,
126.8, 121.9, 120.5, 93.8, 49.7; IR (KBr) ν: 3057, 3014,
2911, 1594, 1571, 1333, 812, 799, 778, 763, 745, 726,
1
for L6. Pale-yellow oil (34%). H NMR (300 MHz,
CDCl3) δ: 11.22 (brs, 1H), 5.35 (s, 1H, C＝CH), 3.55 (q,
J＝6.6 Hz, 2H, N-CH2), 3.00—2.91 (m, 1H, S-CH),
2.77 (t, J＝6.9 Hz, 2H), 2.12 (s, 3H), 1.29 (d, J＝6.6 Hz,
6H); 13C NMR (75 MHz, CDCl3) δ: 175.2, 174.8, 169.1,
119.3, 115.5, 89.3, 43.4, 35.0, 29. 9, 23.0, 19.1; 19F
NMR (282 MHz, CDCl3) δ: －7.08; IR (KBr) ν: 2964,
2928, 2869, 1619, 1593, 1277, 1250, 1185, 1136, 741,
－
＋
1
690 cm ; MS (EI) m/z: 314 (M ), 209 (M－PhCO).
HRMS (EI) calcd for C21H18N2O (M＋) 314.1419, found
314.1418. Anal. calcd for C21H18N2O: C 80.23, H 5.77,
N 8.91; found C 80.19, H 5.80, N 8.83.
－
＋
1
727 cm ; MS (EI) m/z: 255 (M ), 166 (M－CH2SPr-i).
HRMS (EI) calcd for C10H16F3NOS (M＋) 255.0905,
found 255.0905. Anal. calcd for C10H16F3NOS: C 47.05,
H 6.32, N 5.49; found C 47.54, H 6.38, N 5.59.
Typical procedure for the synthesis of the Ni(II)
complexes (1 as an example)
(Z)-3-(2-(Dimethylamino)ethylamino)-1,3-diphe-
nylprop-2-en-1-one (L9) The same procedure as that
1
To a solution of L1 (0.31 g, 1.05 mmol) in toluene
(10 mL) at －78 ℃ was added dropwise a solution of
n-BuLi (0.42 mL, 1.05 mmol, 2.5 mol/L in hexane) over
10 min. The resulting mixture was allowed to warm to
room temperature and stirred for 2 h. After removing
the solvent under reduced pressure, the resulting solid
was mixed with NiPhCl(PPh3)2 (0.71 g, 1.02 mmol) at
golvebox and then cooled toluene (－30 ℃) was added.
The resulting mixture solution was stirred overnight and
then was filtered and concentrated. The yellow solid
was collected at －30 ℃.
for L6. Pale-yellow solid (80%). H NMR (300 MHz,
CDCl3) δ: 11.40 (s, 1H, NH), 7.90—7.88 (m, 2H),
7.47—7.36 (m, 8H), 5.76 (s, 1H), 3.29 (q, J＝6.3 Hz,
2H, N-CH2), 2.43 (t, J＝6.6 Hz, 2H), 2.21 (s, 6H); 13C
NMR (75 MHz, CDCl3) δ: 187.9, 166.1, 140.0, 135.4,
130.3, 129.1, 128.2, 127.8, 127.3, 126.7, 93.1, 59.0,
45.2, 42.5; IR (KBr) ν: 3419, 2818, 2767, 1595, 1567,
1481, 1334, 1064, 1023, 839, 784, 752, 714, 693, 682
－
＋
1
cm ; MS (EI) m/z: 294 (M ), 58 (NMe2). HRMS (EI)
calcd for C19H22N2O (M＋) 294.1732, found 294.1732.
Anal. calcd for C19H22N2O: C 77.52, H 7.53, N 9.52;
1106
www.cjc.wiley-vch.de
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2012, 30, 1105—1113

Highly Selective Ethylene Dimerization to 1-Butene of [O－NX]Ni(II) Complexes
[(1Z,3Z)-3-(2-(Methylthio)ethylimino)-1,3-diphe-
nylprop-1-en-1-olate]NiPh (1) Yield: 0.39 g (91%).
1H NMR (300 MHz, CDCl3) δ: 7.68 (d, J＝6.6 Hz, 2H),
7.55 (d, J＝6.6 Hz, 2H), 7.43—7.18 (m, 8H), 7.03—
6.90 (m, 3H), 5.71 (s, 1H, C＝CH), 3.37—3.31 (m, 1H),
3.25—3.17 (m, 1H), 2.62—2.55 (m, 1H), 2.25—2.21
(m, 1H), 2.07 (s, 3H, S-CH3); 13C NMR (75 MHz,
CDCl3) δ: 172.3, 167.3, 149.1, 140.7, 139.2, 137.3,
129.1, 128.5, 128.1, 127.8, 126.7, 126.3, 125.9, 123.0,
96.7, 52.4, 39.2, 19.8. Anal. calcd for C24H23NNiOS: C
66.69, H 5.36, N 3.24; found C 67.17, H 5.24, N 3.00.
[(1Z,3Z)-3-(2-(Isopropylthio)ethylimino)-1,3-di-
phenylprop-1-en-1-olate]NiPh (6)
Yield: 0.23 g
1
(91%). H NMR (300 MHz, CDCl3) δ: 7.71 (d, J＝6.6
Hz, 2H), 7.56 (d, J＝6.9 Hz, 2H), 7.44—7.19 (m, 8H),
7.00—6.89 (m, 3H), 5.71 (s, 1H, C＝CH), 3.32—3.25
(m, 1H), 3.25—3.16 (m, 1H), 2.73—2.68 (m, 1H), 2.39
(t, J＝6.6 Hz, 2H), 2.31—2.23 (m, 1H), 2.05—1.98 (m,
1H), 1.74—1.70 (m, 2H), 1.76—1.50 (m, 1H), 1.50—
1.31 (m, 2H), 1.31—1.00 (m, 3H); 13C NMR (75 Hz,
CDCl3) δ: 172.0, 167.1, 148.5, 140.8, 139.2, 138.0,
129.0, 128.4, 128.0, 127.8, 126.7, 126.4, 125.5, 122.8,
96.6, 52.9, 47.3, 32.4, 32.1, 26.4, 25.1. Anal. calcd for
C29H31NNiOS: C 69.62, H 6.25, N 2.80; found C 69.66,
H 6.19, N 2.48.
phenylprop-1-en-1-olate]NiPh (2)
Yield: 0.13 g
1
(86%). H NMR (300 MHz, CDCl3) δ: 7.72 (d, J＝6.6
Hz, 2H), 7.58 (d, J＝6.9 Hz, 2H), 7.44—7.20 (m, 8H),
7.02—6.90 (m, 3H), 5.72 (s, 1H, C＝CH), 3.41—3.37
(m, 1H), 3.20—3.15 (m, 1H), 2.60—2.51 (m, 1H), 2.38
(t, J＝6.3 Hz, 2H), 1.54 (d, J＝5.1 Hz, 3H), 1.25 (d, J＝
4.8 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ: 172.0,
167.1, 148.8, 140.7, 139.1, 137.9, 129.1, 128.4, 128.0,
127.9, 126.7, 126.3, 125.6, 122.9, 96.6, 52.7, 39.3, 31.6,
21.8. Anal. calcd for C26H27NNiOS: C 67.85, H 5.91, N
3.04; found C 67.99, H 5.79, N 2.90.
[(1Z,3E)-3-(2-(Isopropylthio)ethylimino)-1-phe-
nylbut-1-en-1-olate]NiPh (7) Yield: 0.59 g (94%). 1H
NMR (300 MHz, CDCl3) δ: 7.71 (dd, J＝2.1, 7.8 Hz,
2H), 7.52 (d, J＝6.6 Hz, 2H), 7.28—7.21 (m, 3H),
6.98—6.87 (m, 3H), 5.69 (s, 1H, C＝CH), 3.59—3.57
(m, 1H), 3.30—3.47 (m, 1H), 2.62—2.52 (m, 3H), 2.03
(s, 3H), 1.50 (br s, 3H), 1.26 (br s, 3H); 13C NMR (75
MHz, CDCl3) δ: 171.5, 165.1, 148.8, 139.3, 137.9,
128.8, 127.8, 126.6, 125.4, 122.7, 96.5, 50.7, 39.0, 31.7,
23.4, 21.7. Anal. calcd for C21H25NNiOS: C 63.34, H
6.33, N 3.52; found C 63.76, H 6.48, N 3.74.
[(1Z,3Z)-1,3-Diphenyl-3-(2-(propylthio)ethylimino)-
1
prop-1-en-1-olate]NiPh (3) Yield: 0.40 g (87%). H
[(2Z,4Z)-5,5,5-Trifluoro-4-(2-(isopropylthio)eth-
ylimino)pent-2-en-2-olate]NiPh (8) Yield: 0.63 g
NMR (300 MHz, CDCl3) δ: 7.70 (d, J＝6.9 Hz, 2H),
7.55 (d, J＝6.9 MHz, 2H), 7.43—7.20 (m, 8H), 7.02—
6.92 (m, 3H), 5.72 (s, 1H, C＝CH), 3.33—3.20 (m, 2H),
2.58—2.51 (m, 2H), 2.35—2.21 (m, 2H), 1.65—1.48
(m, 2H), 0.85 (t, J＝7.2 Hz, 3H); 13C NMR (75 MHz,
CDCl3) δ: 172.2, 167.2, 148.8, 140.7, 139.2, 137.5,
129.1, 128.4, 128.1, 127.8, 126.7, 126.3, 125.7, 122.9,
96.6, 52.7, 38.2, 36.6, 21.6, 13.0. Anal. calcd for
C26H27NNiOS: C 67.85, H 5.91, N 3.04; found C 67.95,
H 6.09, N 2.93.
1
(90%). H NMR (300 MHz, CDCl3) δ: 7.38—7.32 (m,
2H), 6.90—6.86 (m, 3H), 5.42 (s, 1H, C＝CH), 3.62—
3.54 (m, 1H), 3.30—3.24 (m, 1H), 2.53—2.46 (m, 3H),
1.99 (s, 3H), 1.60—1.40 (m, 3H), 1.40—1.25 (m, 3H);
13C NMR (75 MHz, CDCl3) δ: 166.3, 161.0, 160.6,
160.2, 159.8, 145.1, 137.6, 125.6, 124.8, 123.2, 121.0,
117.3, 113.5, 96.3(4), 96.3(1), 51.0, 39.5, 31.1, 23.1,
21.7; 19F NMR (282 MHz, CDCl3) δ: －73.5. Anal.
calcd for C16H20F3NNiOS: C 49.26, H 5.17, N 3.59,
found C 49.70, H 5.42, N 3.59.
{(1Z,3Z)-3-[(2-(tert-Butylthio)ethylimino)-1,3-di-
phenylprop-1-en-1-olate}NiPh (4)
Yield: 0.41 g
[(1Z,3Z)-3-(2-(Dimethylamino)ethylimino)-1,3-di-
1
(87%). H NMR (300 MHz, CDCl3) δ: 7.71 (d, J＝6.6
Hz, 2H), 7.58 (d, J＝6.9 Hz, 2H), 7.43—7.22 (m, 8H),
6.99—6.87 (m, 3H), 5.71 (s, 1H, C＝CH), 3.27 (br s,
2H), 2.43 (br s, 2H), 1.25 (s, 9H); 13C NMR (75 MHz,
CDCl3) δ: 171.9, 167.1, 147.3, 140.8, 139.1, 138.8,
129.0, 128.4, 128.0, 127.8, 126.7, 126.3, 125.3, 122.9,
96.5, 53.0, 50.1, 34.5, 30.0. Anal. calcd for
C27H29NNiOS: C 68.37, H 6.16, N 2.95; found C 68.49,
H 6.32, N 2.96.
phenylprop-1-en-1-olate]NiPh (9)
Yield: 0.18 g
1
(86%). H NMR (300 MHz, CDCl3) δ: 7.87 (d, J＝7.2
Hz, 2H), 7.42—6.88 (m, 13H), 5.69 (s, 1H, C＝CH),
3.10 (t, J＝6.0 Hz, 2H), 3.35 (s, 8H); 13C NMR (75
MHz, CDCl3) δ: 172.1, 166.4, 159.3, 140.0, 139.1,
135.9, 128.7, 128.4, 128.2, 127.7, 126.5, 126.4, 124.9,
121.9, 96.5, 65.2, 49.8, 49.2. Anal. calcd for
C25H26N2NiO: C 69.96, H 6.11, N 6.53; found C 69.51,
H 6.03, N 6.50.
[(1Z,3Z)-1,3-Diphenyl-3-(2-(phenylthio)ethylimi-
no)prop-1-en-1-olate]NiPh (5) Yield: 0.41 g (83%).
1H NMR (300 MHz, CDCl3) δ: 8.41—8.38 (m, 2H),
7.73 (d, J＝6.6 Hz, 2H), 7.49—7.21 (m, 13H), 6.94—
6.82 (m, 3H), 5.79 (s, 1H, C＝CH), 3.25—3.16 (m, 1H),
3.15—3.09 (m, 1H), 3.03—2.83 (m, 1H), 2.48—2.40
(m, 1H); 13C NMR (75 MHz, CDCl3) δ: 172.2, 167.5,
146.4, 140.8, 139.0, 137.7, 133.8, 130.0, 129.6, 129.4,
129.2, 128.5, 128.1, 127.9, 126.8, 126.3, 125.6, 123.0,
96.8, 51.9, 43.2. Anal. calcd for C29H25NNiOS: C 70.47,
H 5.10, N 2.83; found C 70.58, H 4.81, N 2.42.
[(1Z,3Z)-3-(2-(Diphenylphosphino)ethylimino)-
1,3-diphenylprop-1-en-1-olate]NiPh (10) Yield: 0.23
g (89%). 1H NMR (300 MHz, CDCl3) δ: 7.71 (d, J＝6.9
Hz, 2H), 7.59—7.18 (m, 20H), 6.77—6.75 (m, 3H),
5.81 (s, 1H, C＝CH), 3.29 (t, J＝6.3 Hz, 1H), 3.21 (t,
J＝6.3 Hz, 1H), 2.21—2.14 (m, 2H); 13C NMR (75
MHz, CDCl3) δ: 172.2, 167.8, 152.6, 151.9, 141.6,
139.8(3) 139.7(7), 138.0(3), 138.0(0), 133.3, 133.2,
130.6, 130.5(7), 130.3, 129.7, 129.0, 128.5, 128.4, 128.3,
127.8(4), 127.8(2), 126.9, 126.5, 125.5(3), 125.5(1),
122.0, 96.7, 51.4(4), 51.3(7), 32.2, 31.9; 31P NMR (121
MHz, CDCl3) δ: 48.53. Anal. calcd for C35H30NNiOP:
[(1Z,3Z)-3-(2-(Cyclohexylthio)ethylimino)-1,3-di-
Chin. J. Chem. 2012, 30, 1105—1113
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
1107

Xu et al.
FULL PAPER
C 73.71, H 5.30, N 2.46; found C 73.87, H 5.17, N 2.26.
[(1Z,3Z)-3-(2-Phenoxyethylimino)-1,3-diphe-
nylprop-1-en-1-olate]NiPh(PPh3) (11) Yield: 0.53 g
dichloromethane (1 mL) was introduced into the reactor
under nitrogen. After stirring for 10 min at desired tem-
perature, ethylene was continuously fed to maintain the
ethylene pressure at desired pressure for 5 or 10 min.
Then acidified EtOH and heptane (as internal standard)
was injected at －78 ℃ to quench the reaction. Quan-
titative GC analysis of the product was performed
immediately after the termination of the reaction.
1
(92%). H NMR (300 MHz, CDCl3) δ: 7.60—7.54 (m,
7H), 7.35—7.08 (m, 17H), 6.91—6.71 (m, 8H), 6.53—
6.49 (m, 3H), 5.71 (s, 1H, C＝CH), 4.12 (t, J＝6.3 Hz,
2H), 2.94 (t, J＝2.9 Hz, 2H); 13C NMR (75 MHz, C6D6)
δ: 171.6, 170.4, 159.8, 152.7, 152.1, 142.5(2), 142.4(7),
139.3, 138.5, 134.9, 134.7, 132.3, 131.7, 129.8, 129.5,
129.0, 128.3, 128.2, 128.1, 128.0, 127.8, 127.7(7),
127.68, 126.8, 126.5, 122.2, 120.5, 115.2, 98.6, 70.7,
53.5; 31P NMR (121 MHz, CDCl3) δ: 29.00. Anal. calcd
for C47H40NNiO2P: C 76.23, H 5.44, N 1.89; found C
76.48, H 5.41, N 1.93.
Results and Discussion
Synthesis and characterization of the Ni(II) com-
plexes
The ligands were readily available in moderate to
good yields by a known procedure (Scheme 1).[14e-14g]
The structures were well-characterized by 1H, 13C NMR,
MS, elemental analysis, and IR spectra. A signal at
around δ 188 in the 13C NMR spectra of the ligands dis-
plays the C＝O group in β-carbonylenamines.
[(1Z,3Z)-1,3-Diphenyl-3-(pyridin-2-ylmethylimi-
no)prop-1-en-1-olate]NiPh (12) Yield: 0.25 g (81%).
1H NMR (300 MHz, CDCl3) δ: 7.83—6.84 (m, 19H),
13
5.84 (s, 1H, C＝CH), 4.54 (s, 2H); C NMR (75 MHz,
CDCl3) δ: 172.9, 166.6, 164.0, 159.9, 152.7, 139.6,
139.0, 136.8, 136.2, 129.1, 128.8, 128.4, 127.9, 126.6,
126.2, 125.6, 122.7, 122.5, 119.5, 96.9, 59.4. Anal.
calcd for C27H22N2NiO: C 72.20, H 4.94, N 6.24; found
C 71.67, H 5.28, N 6.02.
Scheme 1 Synthesis of the ligands L1—14
R2
R2
+
R1
TsOH H2O
(1Z,3E)-3-[2-(2,6-Dimethylphenylthio)phenyli-
H2N
N
X
H
O
O
toluene, reflux
X
mino)-1-phenylbut-1-en-1-olate]NiPh(PPh3)
(13)
R1
O
1
Yield: 0.20 g (74%). H NMR (300 MHz, CDCl3) δ:
7.61—7.58 (m, 6H), 7.40—7.09 (m, 14H), 7.00—6.91
(m, 4H), 6.46 (t, J＝7.5 Hz, 1H), 6.31—6.16 (m, 4H),
6.05 (d, J＝7.2 Hz, 1H), 5.94 (d, J＝6.9 Hz, 1H), 5.97
(s, 1H, C＝CH), 5.77 (t, J＝7.2 Hz, 1H), 2.52 (s, 6H),
1.84 (s, 3H); 13C NMR (100 MHz, CDCl3) δ: 171.4,
167.4, 151.6, 151.1, 148.4, 144.6, 139.1, 138.5, 135.3,
134.5, 134.4, 132.2, 131.9, 131.5, 130.3, 129.4, 129.1,
129.0, 128.7, 128.4, 128.2, 127.7, 127.6, 127.4, 127.2,
126.3, 125.4, 123.9, 123.5, 123.3, 121.9, 120.3, 95.6,
24.8(1), 24.7(8), 22.0; 31P NMR (121 MHz, CDCl3) δ:
28.8. Anal. calcd for C48H42NNiOPS: C 74.82, H 5.49,
N 1.82; found C 74.42, H 5.68, N 1.48.
L1 — L11
Ph
O
N
H
R
N
H
S
Ph
O
N
Ph
R
L12
L13 R = Me
L14 R = H
R1
R2
X
L
1
2
3
4
5
6
7
8
9
Ph Ph SMe
Ph Ph SPr-i
Ph Ph SPr-n
Ph Ph SBu-t
Ph Ph SPh
Ph Ph SCy
Ph CH3 SPr-i
CH3 CF3 SPr-i
Ph Ph NMe2
{(1Z,3E)-1-Phenyl-3-[2-(phenylthio)phenylimino]-
but-1-en-1-olate}NiPh(PPh3) (14)
Yield: 0.62 g
1
(82%). H NMR (300 MHz, CDCl3) δ: 7.62—7.56 (m,
8H), 7.35—7.10 (m, 14H), 6.96—6.87 (m, 4H), 6.60—
6.53 (m, 2H), 6.45—6.42 (m, 2H), 6.26—6.19 (m, 2H),
6.08—6.06 (m, 1H), 5.89—5.86 (m, 2H), 1.70 (s, 3H).
13C NMR (75 MHz, CDCl3) δ: 171.5(0), 171.4(8), 166.9,
151.4, 150.8, 149.2, 139.1, 138.3(0), 138.2(9), 136.1,
136.0, 134.5(0), 134.4(6), 134.3, 133.5, 132.9, 131.9,
131.3, 129.3(8), 129.3(5), 129.2, 128.7, 128.0, 127.7,
127.6, 127.3, 126.3, 126.1, 125.7, 125.2(9), 125.2(6),
124.6, 124.1, 124.0, 123.5, 120.3(4), 120.3(1), 95.6,
25.1, 25.0; 31P NMR (121 MHz, CDCl3) δ: 28.9. Anal.
calcd for C46H38NNiOPS: C 74.41, H 5.16, N 1.89;
found C 74.50, H 5.25, N 1.83.
10 Ph Ph PPh2
11 Ph Ph OPh
Initially, we tried to prepare the corresponding
nickel complexes by slowly adding the lithium salts of
ligands in toluene to the suspension of NiPhCl(PPh3)2 in
dry toluene, but failed to obtain the corresponding com-
plexes. To our delight, when we modified the procedure
by mixing the lithium salt of L1—L14 with
NiPhCl(PPh3)2 first, followed by adding toluene at
－30 ℃, complexes 1—14 were obtain as air- and
moisture-sensitive solids in good yields (Scheme 2). 1—
14 are easily soluble in toluene, dichloromethane, and
tetrahydrofuran at room temperature and the structures
of 1—14 were well-characterized by 1H, 13C, 31P NMR,
and elemental analysis. Similar to the corresponding
titanium complexes,[14f-14g] 13C NMR analysis of com-
plexes 1—14 showed that the chemical shift higher than
General procedure for ethylene dimerization
To a dry 300 mL stainless-steel autoclave was
charged with dichloromethane (100 mL). Then the de-
sired amount of cocatalyst and the solution of catalyst in
1108
www.cjc.wiley-vch.de
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2012, 30, 1105—1113

Highly Selective Ethylene Dimerization to 1-Butene of [O－NX]Ni(II) Complexes
δ 180 (carbonyl group in the ligands) disappeared and
two signals at around δ 170 were observed. This obser-
vation is confirmed by the X-ray analysis. As shown in
Figure 1, X-ray crystallographic analysis of 7 reveals
that the ligand coordinats nickel atom with oxygen, ni-
trogen, and sulfur atoms. The geometry around nickel
adopts a distorted square planar. The phenyl group at-
tached to Ni lies trans to N(1) with an N(1)-Ni(1)-C(20)
angle of 176.73(13)°. The O(1), N(1), S(1), and C(20)
atoms are nearly coplanar, with O(l) and S(1) occupying
the trans position [O(l)-Ni(1)-S(1): 174.91(8)º,
N(1)-Ni(1)-C(20): 176.73(13)º]. The Ni(1)—N(1) bond
length is 1.932(2) Å. The bond length of O(1)—Ni(1)
(1.863(2) Å) is shorter than that of the reported salicy-
laldiminato nickel(II) complex (O—Ni 1.910(3) Å).[16]
The O(1)—C(9) is lengthened and N(1)—C(7) is short-
ened as compared to the corresponding ligand.[14f] It is
Figure 1 Molecular structure of 7. Thermal ellipsoids are
worthy to note that a strong coordination effect exists
between sulfur and nickel, as the Ni(1)—S(1) bond
length is 2.1389(10) Å (the sum of Van der Waals ra-
dius is 4.37 Å). For each complex, satisfactory elemen-
tal analyses were obtained. Together with both 1H NMR
and 13C NMR spectroscopy analysis, it is deduced that
the molecular structures of complexes 1—6, 8—10 and
12 are similar to that of 7.
drawn at the 50% probability level. Hydrogen atoms are omitted
for clarity. Selected bond distances (Å) and angles (º): Ni(1)—
O(1) ＝ 1.863(2), Ni(1) — N(1) ＝ 1.932(2), Ni(1) — S(1) ＝
2.1389(9), Ni(1) — C(20) ＝ 1.914(3), C(7) — C(8) ＝ 1.413(5),
C(8)—C(9)＝1.369(5), O(1)—C(9)＝1.293(4), N(1)—C(7)＝
1.308(4), O(1)-Ni(1)-C(20) ＝ 87.55(11), O(1)-Ni(1)-N(1) ＝
95.34(11), C(20)-Ni(1)-N(1) ＝ 176.73(13), O(1)-Ni(1)-S(1) ＝
174.91(8), C(20)-Ni(1)-S(1) ＝ 87.37(9), N(1)-Ni(1)-S(1) ＝
89.74(9), C(1)-S(1)-C(17) ＝ 104.7(2), C(1)-S(1)-Ni(1) ＝
99.14(12), C(17)-S(1)-Ni(1)＝108.37(13).
Scheme 2 Synthesis of nickel(II) complexes
R2
N
(1.905(2) Å) and Ni(1)—N(1) (1.926(3) Å) are longer
than that of 7. The O(1)—C(9) bond (1.272(4) Å) is
shorter than that of complex 7, and N(1)—C(7) (1.319(5)
Å) is longer than that of complex 7. The distances be-
tween S and Ni atoms in 13 and 14 (3.363 & 3.458 Å,
respectively) mean that the corresponding SAr groups
coordinate with the metal weakly.
(1) n-BuLi, toluene
L1 - L10, L12
Ni
X
(2) NiPhCl(PPh3)2
toluene
R1
Ph
Ph
O
Ph
1 - 10, 12
Ph
Ph
O
(1) n-BuLi, toluene
N
N
H
(2) NiPhCl(PPh3)2
toluene
OPh
OPh
Ph
Ni
O
Ph
PPh3
L11
Ethylene dimerization
11
In the presence of MAO, complex 2 was selected to
screen the ethylene oligomerization under different
conditions (Table 2). To our delight, the ethylene was
dimerized in very high activity [1.20×106 g/(mol(Ni)•
h•atm)] at 0 ℃ and 10 atm ethylene atmosphere along
with good selectivity towards 1-butene (84.2%). A even
higher activity [1.91×106 g/(mol(Ni)•h•atm)] was ob-
served when prolonging the reaction time (Table 2, En-
try 7). We suppose that the violent exothermic reaction,
which resulted in the rapid rise of the system tempera-
ture, induced rapid isomerization of the formed butene.
When the ethylene dimerization was carried out at 10
atm ethylene pressures, reducing the reaction tempera-
ture from 0 to －15 ℃ resulted in the selectivity in-
crease of 1-butene from 84.2% to 90.2% (Table 2, En-
tries 1 vs. 2), and the 1-butene selectivity reached to
above 99% when the reaction temperature was further
reduced to －78 ℃ (Table 2, Entry 5). As a result, the
lower the temperature, the better the 1-butene selectivity.
However, the activity was sharply reduced to 0.01×106
(1) n-BuLi, toluene
N
R
N
Ni
R
H
S
(2) NiPhCl(PPh3)2
toluene
S
Ph
O
O
Ph
PPh3
R
R
13 R = Me
14 R = H
L13 - L14
To our surprise, signals above δ 20.0 in the 31P NMR
spectra were observed in the case of complexes 11, 13,
and 14, which are assigned as the signals for the
triphenylphosphine coordinated to metal. X-ray analysis
of both 13 and 14 confirmed the molecular structure
(Figures 2 and 3). As showed in Figure 2, L13 acts as a
bidentate ligand, and a PPh3 coordinated to the metal.
The O(1), N(1), P(1), and C(25) atoms constitute a dis-
torted square planar geometry around nickel(II),
with O(l) and C(25) occupying the trans position
[O(l)-Ni(1)-C(25): 168.67(15)º, N(1)-Ni(1)-P(1):
178.83(10)º]. The bond length of both O(1)—Ni(1)
Chin. J. Chem. 2012, 30, 1105—1113
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
1109

Xu et al.
FULL PAPER
Figure 3 Molecular structure of 14. Thermal ellipsoids are
drawn at the 50% probability level. Hydrogen atoms are omitted
for clarity. Selected bond distances (Å) and angles (deg): Ni(1)—
O(1) ＝ 1.9089(16), Ni(1) — N(1) ＝ 1.924(2), Ni(1) — C(23) ＝
1.886(2), Ni(1) — P(1) ＝ 2.1667(7), O(1) — C(9) ＝ 1.279(3),
N(1)—C(7)＝1.324(3), C(7)—C(8)＝1.409(4), C(8)—C(9)＝
1.387(5), N(1)-Ni(1)-P(1) ＝ 172.77(6), C(23)-Ni(1)-O(1) ＝
174.57(9), C(23)-Ni(1)-N(1) ＝ 93.29(9), O(1)-Ni(1)-N(1) ＝
91.60(8), C(23)-Ni(1)-P(1) ＝ 89.83(7), O(1)-Ni(1)-P(1) ＝
85.59(6).
Figure 2 Molecular structure of 13. Thermal ellipsoids are
drawn at the 50% probability level. Hydrogen atoms are omitted
for clarity. Selected bond distances (Å) and angles (º): Ni(1)—
C(25) ＝ 1.880(4), Ni(1) — O(1) ＝ 1.905(2), Ni(1) — N(1) ＝
1.926(3), Ni(1) — P(1) ＝ 2.1713(11), O(1) — C(9) ＝ 1.272(4),
C(7)—C(8)＝1.406(5), C(8)—C(9)＝1.362(5), N(1)—C(7)＝
1.319(5), C(25)-Ni(1)-O(1) ＝ 168.67(15), C(25)-Ni(1)-N(1) ＝
93.40(15), O(1)-Ni(1)-N(1) ＝ 92.15(11), C(25)-Ni(1)-P(1) ＝
88.31(12), O(1)-Ni(1)-P(1) ＝ 86.40(8), N(1)-Ni(1)-P(1) ＝
178.83(10).
Table 1 Crystal data and summary of data collection and refinement details for 7, 13, and 14
Complex
7
13
14
Empirical formula
C21H25NNiOS
C48H42NNiOPS
770.57
C46H38NNiOPS
742.51
Formula weight
398.19
Temperature/K
293(2)
293(2)
133(2)
Wavelength/Å
0.71073
0.71073
0.71073
Crystal system
Orthorhombic
Triclinic
Triclinic
Space group
a/Å
P21
P-1
P-1
10.0376(19)
9.8968(6)
14.0467(9)
18.2858(12)
103.4080(10)
101.9770(10)
101.289(2)
2338.1(3)
2
10.7669(12)
11.6150(12)
16.1448(17)
106.895(2)
90.086(2)
107.532(2)
1833.4(3)
2
b/Å
11.540(2)
c/Å
16.583(3)
α/(°)
β/(°)
γ/(°)
90
90
90
V/Å3
1920.8(6)
Z
4
－
Dc/(Mg•m )
3
1.377
1.095
1.345
Size/mm
0.285×0.226×0.135
0.307×0.269×0.211
－11≤h≤11,
－17≤k≤16,
0≤l≤22
0.525
0.35×0.32×0.20
－13≤h≤13
－14≤k≤14
－20≤l≤20
0.667
－12≤h≤12,
－11≤k≤14,
－20≤l≤19
Limiting indices
Absorption coefficient/mm－
1.127
840
1
F(000)
808
776
1110
www.cjc.wiley-vch.de
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2012, 30, 1105—1113

Highly Selective Ethylene Dimerization to 1-Butene of [O－NX]Ni(II) Complexes
Continued
Complex
θ range for data collection/(°) 2.15 to 26.00
7
13
14
1.54 to 25.50
1.32 to 27.00
Reflections collected/unique
Absorption correction
10376/3738 [R(int)＝0.0340]
8549/8549 [R(int)＝0.0000]
Empirical
13435/7892 [R(int)＝0.0215]
Semi-empirical from equivalents
0.8781 and 0.8000
Empirical
Max. and min. transmission
Refinement method
1.00000 and 0.70928
1.0000 and 0.0968
Full-matrix least-squares on F2 Full-matrix least-squares on F2 Full-matrix least-squares on F2
Data/restraints/parameters
Goodness-of-fit on F2
3738/0/229
8549/0/481
7892/1/520
1.039
0.898
0.951
Final R indices [I > 2σ(I)]
R indices (all data)
R1＝0.0396, wR2＝0.0785
R1＝0.0468, wR2＝0.0813
R1＝0.0598, wR2＝0.1235
R1＝0.1221, wR2＝0.1412
R1＝0.0395, wR2＝0.1178
R1＝0.0510, wR2＝0.1314
Largest diff. peak and hole/
(e•Å )
0.458 and －0.201
0.379 and －0.267
0.318 and －1.084
－
3
g/(mol(Ni)•h•atm) when ethylene was dimerized at
－78 ℃. Corresponding to it, the activity was improved
to 7.54×106 g/(mol(Ni)•h•atm) with the selectivity of
1-butene being only 59.9% when the ethylene dimeriza-
tion was processed at 40 ℃. Decreasing in selectivity
with the rise of temperature is consistent with the rapid
β-H elimination and reinsertion to Ni—H at higher
temperature. The rapid β-H elimination and reinsertion
to Ni—H could also be observed from the fact that the
selectivity of 1-butene reduces to 70.8% when the po-
lymerization proceeds for 10 min (Table 2, Entry 7).
High pressure favors the formation of 1-butene. For
example, butene was obtained in an activity of 1.05×
106 g/(mol(Ni)•h•atm) with 93.9% selectivity toward
1-butene at 15 atm and －15 ℃ (Table 2, Entry 3).
2000 is a preferred Al/Ni ratio as too low Al/Ni ratio
(500) resulted in both a reduced activity and a low
1-butene selectivity (Table 2, Entry 8). The 1-butene
selectivity could be improved to 86.1% when Al/Ni ra-
tio reaches 3000, while the activity was slightly dete-
riorated (Table 2, Entry 9). Et2AlCl also was a good
cocatalyst (Table 2, Entry 12). While activation 2 with
1000 equivalent of Et3Al produced an unfavorable cata-
lyst system (Table 2, Entry 13).
In the presence of MAO, all complexes have been
found to be active in catalyzing the ethylene dimeriza-
tion into butene with excellent selectivity, and in all
cases no polymer was observed. The structures of the
complexes influence both the activity and selectivity
significantly (Table 3). For most of the catalysts bearing
a thioether as a sidearm, the activities are above 1×106
g/(mol(Ni)•h•atm) (Table 3, Entries 1—7). In the cases
of R2 being electron-withdrawing CF3, the activity de-
creased to 0.35×106 g/(mol(Ni)•h•atm) (Table 3, Entry
8). Employing PPh2 as a sidearm group, the activity
reached 3.16×106 g/(mol(Ni)•h•atm) (Table 3, Entry
Table 2 Ethylene dimerization in the presence of 2a
Selectivityc/%
Entry
Cocatalyst
Al∶Ni
Time/min
p/atm
Activityb
Temp./℃
Butene
1-Butene
1
2
MAO
MAO
MAO
MAO
MAO
MAO
MAO
MAO
MAO
MAO
MAO
Et2AlCl
Et3Al
1000
1000
1000
1000
1000
1000
1000
500
0
－15
－15
－60
－78
0
5
5
10
10
15
15
15
5
1.20
1.05
1.05
0.08
0.01
0.20
1.91
0.21
1.91
1.45
7.54
1.08
0.05
＞99
＞99
＞99
＞99
＞99
＞99
＞99
＞99
＞99
＞99
85.7d
＞99
＞99
84.2
90.2
93.9
96.0
＞99
80. 8
70.8
78.3
84.0
86.1
59.9
81.8
70.9
3
5
4
5
5
5
6
5
7
0
10
5
10
10
10
10
10
10
10
8
0
9
2000
3000
1000
1000
1000
0
5
10
11
12
13
0
5
40
0
5
5
0
5
a Catalyst (0.46 mg, 1 μmol), MAO (1.5 mol/L in toluene), 100 mL CH2Cl2. b In unit of 106 g/(mol(Ni)•h•atm). c Determined by GC and GC-MS. d Hexenes
were observed.
Chin. J. Chem. 2012, 30, 1105—1113
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
1111

Xu et al.
FULL PAPER
Table 3 Some Results for Ethylene Dimerization catalyzed by Complexes 1—14
Selectivityb,c/%
Entrya
Complex
Activity [106 g/(mol(Ni)•atm•h)]
Butene
95.68
>99
1-Butene
1
2
1.84
1.20
5.20
3.14
2.63
1.18
2.27
0.35
0.91
3.16
9.35
1.03
8.44
4.68
14.25
81.26
84.17
65.70
82.25
74.77
86.58
77.03
87.68
87.02
18.89
12.63
85.29
10.12
11.14
15.89
1
2
3
98.44
>99
3
4
4
5
>99
5
6
>99
6
7
94.05
>99
7
8
8
9
>99
9
10
11
12
13
14
15d
97.18
90.87
>99
10
11
12
13
14
2
89.77
90.93
89.65
b
a 1 μmol of catalyst, MAO (1 mmol, 1.5 mol/L in heptane), Al∶Ni＝1000, 100 mL CH2Cl2, 5 min, 0 ℃, 10 atm. Determined by GC and GC-MS.
c Hexene and octene were also observed. d 1 μmol of Ph3P was added.
References
10). For pyridine-containing complex 12, an activity of
1.03×106 g/molNi•atm•h was achieved. Complexes 11,
13 and 14 gave excellent activities [up to 9.35×106
g/(mol(Ni)•h•atm)]. However, in these cases, the selec-
tivities of 1-butene were only about 10%. When com-
plex 2 was employed in the presence of one equivalent
of Ph3P, the oligomerization activity was improved to
14.25×106 g/(mol(Ni)•h•atm), and correspondingly, the
selectivity for 1-butene reduced to 15.89%.
[1] (a) Skupinska, L. Chem. Rev. 1991, 91, 613; (b) Ittel, S. D.; Johnson,
L. K.; Brookhart, M. Chem. Rev. 2000, 100, 1169; (c) Gibson, V. C.;
Spitzmesser, S. K. Chem. Rev. 2003, 103, 283; (d) Gibson, V. C.;
Redshaw, C.; Solan, G. A. Chem. Rev. 2007, 107, 1745; (e) Board-
man, B. M.; Bazan, G. C. Acc. Chem. Res. 2009, 42, 1597; (f)
Nakamura, A.; Ito, S.; Nozaki, K. Chem. Rev. 2009, 109, 5215; (g)
Forestière, A.; Olivier-Bourbigou, H.; Saussine, L. Oil Gas Sci.
Technol. 2009, 46, 649.
[2] Applied Homogeneous Catalysis with Organometallic Compounds,
Ed.: Vogt, D., VCH, Weinheim, 2002.
[3] Keim, W.; Kowalldt, F. H.; Goddard, R.; Krüger, C. Angew. Chem.,
Int. Ed. Engl. 1978, 17, 466.
Conclusions
[4] Klabunde, U.; Ittel, S. D. J. Mol. Catal. 1987, 41, 123.
[5] Klabunde, U.; Muhlhaupt, R.; Herskowitz, T.; Janowicz, A. H.;
Calabrese, J.; Ittel, S. D. J. Polym. Sci., Polym. Chem. 1987, 25,
1989.
A series of β-ketoimine-derived nickel(II) complexes
have been synthesized and characterized. X-ray analysis
proved that the structures of the complexes deeply de-
pend on the properties of the pendant coordination
group. In the presence of MAO, these nickel(II) com-
plexes showed very high activity [up to 14.25×106
g/(mol(Ni)•h•atm)] toward ethylene dimerization. Good
selectivity for 1-butene is also obtained when the pen-
dant groups coordinate to nickel. Under the optimal
conditions, the selectivity towards 1-butene reaches to
above 99%. Further studies on the mechanism are under
investigation in our laboratory.
[6] (a) Starzewski, K. A.; Witte, J. Angew. Chem., Int. Ed. Engl. 1989,
24, 599; (b) Pietsch, J.; Braunstein, P.; Chauvin, Y. New J. Chem.
1998, 467; (c) Heinicke, J.; He, M.; Dal, A.; Klein, H.; Hetche, O.;
Keim, W.; Flörke, U.; Haupt, H. Eur. J. Inorg. Chem. 2000, 431; (d)
Soula, R.; Broyar, J. P.; Flauro, M. F.; Tomov, A.; Spitz, R.; Claverie,
J.; Drujon, X.; Malinge, J.; Saudemont, T. Macromolecules 2001, 34,
2438; (e) Gibson, V. C.; Tomov, A.; White, A. J. P.; Williams, D. J.
Chem. Commun. 2001, 719; (f) Gibson, V. C.; Tomov, A. Chem.
Commun. 2001, 1964; (g) Heinike, J.; Köhler, M.; Peulecke, N.; He,
M.; Kindermann, M. K.; Keim, W.; Fink, G. Chem. Eur. J. 2003, 9,
6093; (h) Heinike, J.; Köhler, M.; Peulecke, N.; Keim, W. J. Catal.
2004, 225, 16; (i) Kuhn, P.; Sémeril, D.; Jeunesse, C.; Matt, D.; Lutz,
P.; Welter, R. Eur. J. Inorg. Chem. 2005, 1477; (j) Kuhn, P.; Sémeril,
D.; Jeunesse, C.; Matt, D.; Neuburger, M.; Mota, A. Chem. Eur. J.
2006, 12, 5210; (k) Kuhn, P.; Sémeril, D.; Jeunesse, C.; Matt, D.;
Lutz, P. J.; Louis, R.; Neuburger, M. Dalton Trans. 2006, 3647; (l)
Kuhn, P.; Sémeril, D.; Matt, D.; Chetcuti, M. J.; Lutz, P. Dalton
Trans. 2007, 515; (m) Kermagoret, A.; Braunstein, P. Dalton Trans.
Acknowledgement
We are grateful for the financial support from the
National Natural Science Foundation of China (Nos.
20821002 and 21174159) and Chinese Academy of
Sciences.
1112
www.cjc.wiley-vch.de
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2012, 30, 1105—1113

Highly Selective Ethylene Dimerization to 1-Butene of [O－NX]Ni(II) Complexes
2008, 822.
Chin.. Univ. 2005, 26, 1215 (in Chinese); (c) Hou, J.; Sun, W.-H.;
[7] (a) Martin, M. E.; Folli, C.; Walter, O.; Doring, M. J. Mol. Catal. A:
Chem. 2005, 229, 177; (b) Dyer, P. W.; Fawcett, J.; Hanton, M. J.
Organometallics 2008, 27, 5082; (c) Flpper, J.; Kooijman, H.; Lutz,
M.; Spek, A. L.; van Leeuwen, P. W. N. M.; Elsevier, C. J.; Kamer, P.
C. J. Organometallics 2009, 28, 1180; (d) Chavez, P.; Rios, I. G.;
Kermagoret, A.; Pattacini, R.; Meli, A.; Bianchini, C.; Giambastiani,
G.; Braunstein, P. Organometallics 2009, 28, 1776; (e) Flapper, J.;
van Leeuwen, P. W. N. M.; Elsevier, C. J.; Kamer, P. C. J. Or-
ganometallics 2009, 28, 3264.
[8] (a) Yang, P.; Yang, Y.; Zhang, C.; Yang, X.-J.; Hu, H.-M.; Gao, Y.;
Wu, B. Inorg. Chim. Acta 2009, 362, 89; (b) Liu, F.-S.; Gao, H.-Y.;
Song, K.-M.; Zhao, Y.; Long, J.-M.; Zhang, L.; Zhu, F.-M.; Wu, Q.
Polyhedron 2009, 28, 673; (c) Liu, F.-S.; Gao, H.-Y.; Song, K.-M.;
Zhang, L.; Zhu, F.-M.; Wu, Q. Polyhedron 2009, 28, 1386; (d)
Mukherjee, S.; Patel, B. A.; Bhaduri, S. Organometallics 2009, 28,
3074; (e) Song, S.-J.; Li, Y.; Redshaw, C.; Wang, F.-S.; Sun, W.-H. J.
Organomet. Chem. 2011, 696, 3772.
[9] Kermagoret, A.; Braunstein, P. Dalton Trans. 2008, 1564.
[10] Wang, K.; Patil, A. O.; Zushma, S.; McConnachie, J. M. J. Inorg.
Biochem. 2007, 101, 1883.
[11] (a) Speiser, F.; Braunstein, P.; Saussine, L. Dalton Trans. 2004, 1539;
(b) Yang, Q.-Z.; Kermagoret, A.; Agostinho, M.; Siri, O.; Braunstein,
P. Organometallics 2006, 25, 5518; (c) Kermagoret, A.; Tomicki, F.;
Braunstein, P. Dalton Trans. 2008, 2945.
Zhang, S.; Ma, H.; Deng, Y.; Lu, X. Organometallics 2006, 25, 236;
(d) Sun, W.-H.; Wang, K.; Wedeking, K.; Zhang, D.; Zhang, S.; Cai,
J.; Li, Y. Organometallics 2007, 26, 4781; (e) Hao, P.; Zhang, S.;
Sun, W.-H.; Shi, Q.; Adewuyi, S.; Lu, X.; Li, P. Organometallics
2007, 26, 2439; (f) Armitage, A. P.; Champouret, Y. D. M.; Grigoli,
H.; Pelletier, J. D. A.; Singh, K.; Solan, G. A. Eur. J. Inorg. Chem.
2008, 4597; (g) Yang, Y.; Yang, P.; Zhang, C.; Li, G.; Yang, X.-J.;
Wu, B.; Janiak, C. J. Mol. Catal. A: Chem. 2008, 296, 9; (h) Gao, R.;
Zhang, M.; Liang, T.; Wang, F.; Sun, W.-H. Organometallics 2008,
27, 5641; (i) Xiao, L.; Zhang, M.; Gao, R.; Cao, X.; Sun, W.-H. Aust.
J. Chem. 2010, 63, 109.
[14] (a) Hu, W.-Q.; Sun, X.-L; Wang, C.; Gao, Y.; Tang, Y.; Shi, L.-P.;
Xia, W.; Sun, J.; Dai, H.; Li, X.; Yao, X.; Wang, X. Organometallics
2004, 23, 1684; (b) Wang, C.; Sun, X.-L.; Guo, Y.-H.; Gao, Y.; Liu,
B.; Ma, Z.; Xia, W.; Shi, L.-P.; Tang, Y. Macromol. Rapid Commun.
2005, 26, 1609; (c) Wang, C.; Ma, Z.; Sun, X.-L.; Gao, Y.; Guo,
Y.-H.; Tang, Y.; Shi, L.-P. Organometallics 2006, 25, 3259; (d) Gao,
M.-L.; Wang, C.; Sun, X.-L.; Qian, C.-T.; Ma, Z.; Bu, S.; Tang, Y.;
Xie, Z.-W. Macromol. Rapid Commun. 2007, 28, 1511; (e) Yang,
X.-H.; Sun, X.-L.; Han, F.-B.; Liu, B.; Tang, Y.; Wang, Z.; Gao,
M.-L.; Xie, Z.-W.; Bu, S.-Z. Organometallics 2008, 27, 4618; (f)
Yang, X.-H.; Wang, Z.; Sun, X.-L.; Tang, Y. Dalton Trans. 2009,
8945; (g) Yang, X.-H.; Liu, C.-R.; Wang, C.; Sun, X.-L.; Guo, Y.-H.;
Wang, X.-K.; Wang, Z.; Xie, Z.-W.; Tang, Y. Angew. Chem., Int. Ed.
Engl. 2009, 48, 8099.
[15] Han, F.-B.; Zhang, Y.-L.; Sun, X.-L.; Li, B.-G.; Guo, Y.-H.; Tang, Y.
Organometallics 2008, 27, 1924.
[16] (a) Wang, C.-M.; Friedrich, S.; Younkin, T. R.; Li, R.-T.; Grubbs, R.
H. Organometallics 1998, 17, 3149; (b) Younkin, T. R.; Connor, E.
F.; Henderson, J. I.; Friedrich, S. K.; Grubbs, R. H.; Bansleben, D. A.
Science 2000, 287, 460.
[12] (a) Kunrath, F. A.; de Souza, R. F.; Casagrande, Jr. O. L.; Brooks, N.
R.; Young, Jr. V. G. Organometallics 2003, 22, 4739; (b) Ajellal, N.;
Kuhn, M. C. A.; Boff, A. D. G.; Hörner, M.; Thomas, C. M.;
Carpentier, J. F.; Casagrande, Jr. O. L. Organometallics 2006, 25,
1213; (c) de Oliveira, L. L.; Campedelli, R. R.; Kuhn, M. C. A.;
Carpentier, J.-F.; Casagrande, Jr. O. L. J. Mol. Catal. A: Chem. 2008,
288, 58; (d) Ulbrich, A. H. D. P. S.; Bergamo, A. L.; Casagrande, Jr.
O. L. Catal. Commun. 2011, 16, 245.
[17] (a) Fernelius, W. C.; Bryant, B. E. Inorg. Synth. 1957, 5, 105; (b)
Schunn, R. A. Inorg. Synth. 1972, 13, 124; (c) Hidai, M.; Kashiwagi,
T.; Ikeuchi, T.; Uchida, Y. J. Organomet. Chem. 1971, 30, 279.
[13] (a) Su, B.; Zhao, J.; Sun, W. Sci. China Ser. B Chem. 2005,
48(Suppl.), 45; (b) Fan, R.; Zhu, D.; Mu, Y.; Li, G.; Feng, S. Chem. J.
(Pang, B.; Qin, X.)
Chin. J. Chem. 2012, 30, 1105—1113
© 2012 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
1113