Postsynthetic modification of IRMOF-3 with a copper iminopyridine complex as heterogeneous catalyst for the synthesis of 2-aminobenzothiazoles

Article abstract of DOI:10.1002/aoc.3109

A copper iminopyridine complex has been immobilized on to a metal-organic framework (MOF) through postsynthetic modification of IRMOF-3. The modified MOFs were fully demonstrated by using a variety of methods, and the structural integrity of the modified

Full text of DOI:10.1002/aoc.3109

Full Paper
Received: 3 November 2013
Accepted: 10 November 2013
Published online in Wiley Online Library: 20 January 2014
(wileyonlinelibrary.com) DOI 10.1002/aoc.3109
Postsynthetic modification of IRMOF-3 with a
copper iminopyridine complex as
heterogeneous catalyst for the synthesis of
2-aminobenzothiazoles
Jie Liua,b, Xiaobin Zhangb, Jin Yangb and Lei Wangb,c*
A copper iminopyridine complex has been immobilized on to a metal–organic framework (MOF) through postsynthetic mod-
ification of IRMOF-3. The modified MOFs were fully demonstrated by using a variety of methods, and the structural integrity of
the modified MOFs has been confirmed by powder X-ray diffraction (XRD). Furthermore, it was shown that the modified
IRMOF-3 can act as an efficient solid catalyst for the synthesis of 2-aminobenzothiazoles via the reaction of 2-iodoanilines with
isothiocyanates in a heterogeneous manner. Moreover, the catalyst could be facilely separated from the reaction mixture and
reused for six consecutive cycles without significant degradation in catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd.
Additional supporting information may be found in the online version of this article at the publisher’s web site.
Keywords: metal–organic framework; postsynthetic modification; copper iminopyridine complex; heterogeneous catalyst;
2-aminobenzothiazoles
formation of a 3D-framework structure.[13] Direct functionalization
consists in selecting an already functional linker which is directly
Introduction
Metal–organic frameworks (MOFs) are porous crystalline mate-
rials composed of cationic systems that behave like nodes with
polytopic organic ligands acting as spacers.[1] The ability to syn-
thesize a wide range of MOFs has made them attractive materials
for applications in gas sorption, separations and catalysis.[2] Com-
pared to conventionally used microporous and mesoporous
inorganic materials, these metal–organic structures exhibit the
potential for more flexible rational design, by controlling the size
and functionalization of the organic linkers.[3] Throughout the
past several years, several reactions have been carried out using
conventional MOFs as heterogeneous catalysts such as alkene
oxidation,[4] aldol condensation,[5] hydrogenation,[6] and epoxide
ring-opening,[7] Suzuki cross-coupling,[8] transesterification reac-
tion[9] and Knoevenagel condensation.[10] In comparing with ho-
mogeneous reactions, the use of heterogeneous MOFs catalysts
simplifies the reaction work-up by requiring only filtration to sep-
arate the catalyst from the product for reuse. However, one of the
challenges with MOF-based catalysis is that few systems achieve
all of the desired features for a heterogeneous catalyst, including
high activity, robustness (recyclability) and excellent selectivity.
Nevertheless, different strategies can be adopted in order to pre-
pare MOFs with catalytically active functional organic sites.
Recently, postsynthetic modification of MOFs has been shown
to be a general, practical approach for incorporating a wide range
of functional groups into MOFs.[11] Several recent studies have
shown that specialized functionalities can be introduced into
porous MOFs through a postsynthetic modification approach.[12]
Yaghi’s group first reported an amine-functionalized porous MOF,
IRMOF-3 (Isoreticular Metal–Organic Frameworks), with a cubic
structure having amino groups that do not take part in the
used in the synthesis through self-assembly, whereas post-
functionalization modifies the organic part of the solid by a chem-
ical reaction which takes place within the porous framework.
Amino-derived MOFs have been shown to be excellent platforms
for the grafting of various synthons, such as isocyanates, anhydride
acids, aldehydes and ketones.[14]
2-Aminobenzothiazoles, one of the important classes of het-
erocyclic compounds, have been found in many pharmaceuticals
and agrochemicals that show prominent biological activities with
applications in drug discovery since Hugerschoff’s synthesis of
2-aminobenzothiazoles through a reaction of arylthioureas with
liquid bromine.[15] In recent years, considerable effort has been
made in the development of efficient strategies for their prepara-
tion. Conventionally, the majority of efficient methods include
the transition metals, like palladium-, copper-, and iron-catalyzed
tandem reactions of 2-halobenzenamines and isothiocyanates,
to prepare 2-aminobenzothiozoles.[16] Most recently,
a
*
Correspondence to: Lei Wang, Department of Chemistry, Huaibei Normal
University, Huaibei, Anhui 235000, People’s Republic of China. Email:
leiwang@chnu.edu.cn
a College of Chemistry, Chemical Engineering and Materials Science, Soochow
University, Suzhou Jiangsu 215123, People’s Republic of China
b Department of Chemistry, Huaibei Normal University, Huaibei Anhui 235000,
People’s Republic of China
c
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, People’s
Republic of China
Appl. Organometal. Chem. 2014, 28, 198–203
Copyright © 2014 John Wiley & Sons, Ltd.

IRMOF-3-PC-Cu as catalyst for the synthesis of 2-aminobenzothiazoles
polymer-supported copper catalyst system has been applied to
this reaction.[17]
activation solvent was decanted and freshly replenished three
times. The solvent was removed under vacuum at room temper-
ature, yielding the porous material, IRMOF-3.
In continuing our efforts to develop efficient heterogeneous
catalysts for organic transformations from the viewpoint of
green chemistry,[18] we here report the synthesis of a recoverable
and highly active metal–organic framework (IRMOF-3)-anchored
iminopyridine–copper catalyst and its application for the synthesis
of 2-aminobenzothiazoles via the reaction of 2-iodoanilines with
isothiocyanates (Scheme 1). The catalyst shows high catalytic
activity in the tandem reactions of 2-iodoanilines with various
isothiocyanates. Easy catalyst recovery and excellent recycling effi-
ciency of the catalyst make it as an ideal heterogeneous catalytic
system for the synthesis of 2-aminobenzothiazoles.
Synthesis of IRMOF-3-PC
Freshly prepared IRMOF-3 (270 mg, ~1.0 mmol equiv. of ―NH2)
was dispersed in 20 ml dried toluene. To this slurry, 0.3 ml
2-pyridinecarboxaldehyde was dropwise added at room tempera-
ture and the mixture was allowed to stand for 3 days. The solution
was then decanted and the crystals were collected by filtration un-
der vacuum, washed with CH2Cl2 and dried in air at 60°C, yielding
the IRMOF-3-PC (260 mg). Elemental analysis was performed on
samples outgassed under vacuum (100°C, 8 h). IR (KBr, cmÀ1):
3327 (br, νNH2), 1623, 1567, 1502, 1421, 1380, 1275, 1069.
Experimental
Synthesis of IRMOF-3-PC-CuI
General Remarks
IRMOF-3-PC (0.30 g) was suspended in 15 ml CH3CN. To this
slurry, a solution of CuI (19 mg, 0.10 mmol) in 5 ml CH3CN was
dropwise added at room temperature, and the mixture was
allowed to stand for 12 h. The sample was collected by filtration
under vacuum, washed twice with CH3CN and dried in air at
60°C, yielding the IRMOF-3-PC-CuI (241 mg), with a loading of
0.086 mmol gÀ1 copper by ICP analysis. Elemental analysis was
performed on samples outgassed under vacuum (100°C, 8 h): IR
(KBr, cmÀ1): 3291 (br, νNH2), 1615, 1570, 1505, 1420, 1378,
1277, 1070.
Chemicals were purchased from commercial suppliers and used
without purification prior to use. All 1H and 13C NMR spectra were
recorded at 400 MHz using Bruker FT-NMR spectrometers. Ele-
mental analysis was performed on a Vario El III elementar. FT-IR
spectra were obtained with an AVATAR 360 FT-IR spectrometer
(Thermo Nicolet). High-resolution mass spectroscopic data of
the products were collected on a Waters Micromass GCT instru-
ment using EI (70 eV) or an Agilent Technologies 6540 UHD Accu-
rate-Mass Q-TOF liquid chromatograph–mass spectrometer using
electrospray ionization (ESI). The Cu content was determined by
Jarrell-Ash 1100 inductively coupled plasma (ICP) analysis. The
elemental concentration distribution on the sample was verified
Typical Procedure for the Synthesis of
2-Aminobenzothiazoles
by energy-dispersive X-ray analysis (EDX, Horiba 7593H). Products
were purified by flash chromatography on 230–400 mesh silica
gel, SiO2.
A mixture of 2-iodoaniline (0.20 mmol), phenyl isothiocyanate
(0.22 mmol), DABCO (0.40 mmol, 2 equiv.) and IRMOF-3-PC-CuI
(30 mg, containing Cu 0.0025 mmol), and toluene (1.0 ml) was
stirred at 60°C under nitrogen atmosphere. After completion of
the reaction as indicated by thin-layer chromatography, the mix-
ture was cooled to room temperature, Et2O (10.0 ml) was added
and the mixture stirred for 10 min to ensure product removal
from the catalyst. As catalyst was precipitated to the bottom of
the flask, the organic layer was decanted and the residue was
washed with Et2O (2 × 5.0 ml). The combined organic layers were
concentrated, and then the residue was purified by flash chroma-
tography on silica gel to provide the corresponding pure product.
Synthesis of IRMOF-3
IRMOF-3 was prepared using a method previously reported in the
literature.[13a] 2-Aminobenzene-1,4-dicarboxylic acid (0.75 g,
4.1 mmol) and zinc nitrate tetrahydrate (3.0 g, 11.0 mmol) were
dissolved in 100 ml N,N-diethylformamide with stirring in a
1000 ml wide-mouth glass jar. The jar was tightly capped and
placed in a 100°C oven for 18 h to yield cubic crystals. After
decanting the hot mother liquor and rinsing with DMF, the prod-
uct was immersed in chloroform for 3 days, during which the
N-Phenylbenzo[d]thiazol-2-amine
(3a)[16c]
N-(4-Chlorophenyl)benzo[d]
thiazol-2-amine (3b)[16c]
N-(4-Nitrophenyl)benzo[d]thiazol-
2-amine (3c)[16c]
N-(25-Dimethoxyphenyl)benzo[d]
thiazol-2-amine (3d)[17]
N-(35-Di(trifluoromethyl)phenyl)
benzo[d]thiazol-2-amine (3e)[17]
N-(p-Tolyl)benzo[d]thiazol-2-amine
(3f)[16c]
N-(m-Tolyl)benzo[d]thiazol-2-amine
(3g)[17]
N-(4-Methoxyphenyl)benzo[d]
thiazol-2-amine (3h)[16c]
N-(o-Tolyl)benzo[d]thiazol-2-amine
Scheme 1. Preparation of postsynthetic modification of IRMOF-3 with a copper iminopyridine complex
as heterogeneous catalyst for the synthesis of 2-aminobenzothiazoles.
(3i)[16c]
Appl. Organometal. Chem. 2014, 28, 198–203
Copyright © 2014 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/aoc

J. Liu et al.
6-Fluoro-N-phenylbenzo[d]thiazol-2-amine (3j)[16e]
system (IRMOF-3-PC). The functionalized IRMOF-3-PC was then
treated with CuI to generate the corresponding Cu(I)-containing
catalyst material, IRMOF-3-PC-CuI. The synthetic pathway for the
functionalized MOF system is depicted in Scheme 1. IRMOF-3
was easily prepared via the reaction of 2-aminoterephthalate
with Zn(NO3)2.6H2O according to procedure reported in previous
literature,[14f] and kept immersed in chloroform for 3 days before
post-synthesis modification to remove included DMF solvent
molecules. Subsequently, amine functionalization was prepared
by dissolving 2-pyridinecarboxaldehyde in dried toluene and
treating the resulting solution with freshly prepared IRMOF-3.
The obtained solid was washed with toluene sufficiently and
dried under vacuum to remove the unreacted material. The final
step to prepare the Cu(I)-containing material, IRMOF-3-PC-Cu,
involved reacting CuI with the functionalized IRMOF-3-PC.
The IRMOF-3 before and after functionalization was fully
characterized. Initially, the phase purity of IRMOF-3-PC-CuI was
established by powder X-ray diffraction (XRD), where the
observed diffraction pattern closely matched the predicted from
the single-crystal structure (Fig. 1).
To determine the thermal stability of the functionalized IRMOF-
3-PC and IRMOF-3-PC-Cu, TGA of the functionalized MOFs was
performed. IRMOF-3-PC-CuI showed identical thermal stability
to IRMOF-3-PC, with the major weight loss between 350 and
550°C, due to combustion of the organic part of the framework
(supporting information, Fig. I). An important structural feature
of the MOF material is that they possess nanoscale pores;
however, the existence of a side chain on the link may decrease
the pore size. The N2 adsorption–desorption experiment was
recorded in order to evaluate the porosity of the modified MOF
material (IRMOF-3-PC-CuI). The experimental result shows a
decrease in BET (Brunauer–Emmett–Teller) surface area to
477 m2 gÀ1 after IRMOF-3 was modified due to the added CuI
to IRMOF-3 (supporting information, Fig. II). Similar results have
been observed in other MOFs after post-modification.[13] Further-
more, the copper content of the IRMOF-3-PC-CuI was examined
by combined elemental analysis, TGA, EDX and ICP analysis. The
crystallized particles of IRMOF-3-PC-CuI revealed by EDX consist
mainly of Zn, along with a small amount of Cu, and the Zn:Cu ra-
tio appears to be 50:1, corresponding to 2.7% of the ―NH2
groups having been functionalized (supporting information,
Fig. III). ICP analysis also indicated that a weight loading of 0.55
wt% (0.086 mmol gÀ1) copper in IRMOF-3-PC-CuI, corresponding
6-Fluoro-N-(p-tolyl)benzo[d]thiazol-2-amine (3k)[16e]
6-Fluoro-N-(4-methoxyphenyl)benzo[d]thiazol-2-amine (3l)[16d]
6-Fluoro-N-(4-nitrophenyl)benzo[d]thiazol-2-amine (3m)[16e]
N-Phenyl-6-(trifluoromethyl)benzo[d]thiazol-2-amine (3o)[16e]
N-(4-Chlorophenyl)-6-(trifluoromethyl)benzo[d]thiazol-2-amine
(3q)[16e]
have been characterized by comparing their 1H and 13C spectral data
(see supporting information) with those reported in the literature.
N-(4-Chlorophenyl)-6-fluorobenzo[d]thiazol-2-amine (3n)
White solid; m.p. 204.1–205.2°C. IR (KBr, cmÀ1): 3211, 1622. 1H
NMR (400 MHz, DMSO-d6): δ = 10.59 (br, s, 1H, N―H), 7.78
(d, J = 9.2 Hz, 2H, 2′,6′-H, N―Ph), 7.69 (dd, J = 8.8, 2.4 Hz, 1H,
7-H), 7.47 (dd, J = 8.8, 4.8 Hz, 1H, 4-H), 7.36 (d, J = 8.8 Hz, 2H,
3′,5′-H, N―Ph), 7.13 (dt, J = 8.8, 2.4 Hz, 1H, 5-H). 13C NMR
1
(100 MHz, DMSO-d6): δ = 161.67 (2-C, Ph), 158.48 (d, JCF = 237.0
Hz, 6-C, Ph), 149.03 (9-C, Ph), 139.86 (1′-C, N―Ph), 131.59 (d, 3JCF
=
11.40 Hz, 8-C, Ph), 129.23 (2C, 3′,5′-C, N―Ph), 125.97 (4′-C,
3
N―Ph), 120.47 (d, JCF = 9.0 Hz, 4-C, Ph), 119.61 (2C, 2′,6′-C,
2
2
N―Ph), 113.88 (d, JCF = 23.7 Hz, 5-C, Ph), 108.36 (d, JCF = 27.3
Hz, 7-C, Ph). Elemental analysis: calcd for C13H8ClFN2S: C, 56.02;
H, 2.89; N, 10.05%; found C, 56.14; H, 2.76; N, 10.11%. HRMS (EI);
calcd for C13H8ClFN2S [M]+ 278.0081; found 278.0079.
N-(p-Tolyl)-6-(trifluoromethyl)benzo[d]thiazol-2-amine (3p)
White solid; m.p. 194.3–196.5°C. IR (KBr, cmÀ1): 3181, 1625. 1H
NMR (400 MHz, DMSO-d6): δ = 10.64 (s, 1H, N―H), 8.21
(s, 1H, 7-H), 7.68–7.66 (m, 1H, 4-H), 7.64 (d, J = 8.4 Hz, 2H, 2′,6′-H,
N―Ph), 7.59–7.57 (m, 1H, 5-H), 7.16 (d, J = 8.4 Hz, 2H, 3′,5′-H,
N―Ph), 2.25 (s, 3H, ―CH3). 13C NMR (100 MHz, DMSO-d6):
δ = 165.05 (2-C, Ph), 155.61 (9-C, Ph), 138.15 (1′-C, N―Ph),
132.26 (4′-C, N―Ph), 131.12 (8-C, Ph), 129.89 (2C, 3′,5′-C, N―Ph),
1
3
125.14 (q, JCF = 269.9 Hz, ―CF3), 123.21 (q, JCF = 15.0 Hz, 5-C,
2
Ph), 122.66 (q, JCF = 31.7 Hz, 6-C, Ph), 119.39 (4-C, Ph), 119.20
(q, JCF = 4.0 Hz, 7-C, Ph), 118.89 (2C, 2′,6′–C, N―Ph), 20.85
3
(―CH3). Elemental analysis: calcd for C15H11F3N2S: C, 58.43; H,
3.60; N, 9.09%; found C, 58.38; H, 3.64; N, 9.01%. HRMS (EI): calcd
for C15H11F3N2S ([M]+); 308.0595; found 308.0594.
4,6-Dichloro-N-phenylbenzo[d]thiazol-2-amine (3r)
White solid; m.p. 149.5–151.3°C. IR (KBr, cmÀ1): 3119, 1607. 1H
NMR (400 MHz, CDCl3): δ = 8.09 (s, 1H, N―H), 7.49 (d, J = 2.0 Hz,
1H, 7-H), 7.45 (br, 2H, 2′,6′-H, N―Ph), 7.42 (d, J = 2.4
Hz, 2H, 3′,5′-H, N―Ph), 7.37 (d, J = 2.0 Hz, 1H, 5-H), 7.25–7.20 (m,
1H, 4′-H, N―Ph). 13C NMR (100 MHz, CDCl3): δ = 165.49 (2-C, Ph),
147.39 (9-C, Ph), 139.15 (1′–C, N―Ph), 131.81 (6-C, Ph), 129.71
(2C, 3′,5′-C, N―Ph), 127.39 (8-C, Ph), 126.61 (5-C, Ph), 125.31
(4-C, Ph), 124.09 (4′–C, N―Ph), 120.90 (2C, 2′,6′-C, N―Ph),
119.08 (7-C, Ph). Elemental analysis: calcd for C13H8Cl2N2S: C,
52.89; H, 2.73; N, 9.49%; found C, 52.87; H, 2.69; N, 9.45%. HRMS
(ESI): calcd for C13H9Cl2N2S [M+H]+ 294.9864; found 294.9857.
Results and Discussion
In previous studies, the condensation of the amine-functionalized
framework UMCM-1-NH2 and 2-pyridinecarboxaldehyde was
been reported by Yaghi’s group.[14f] Herein, in a parallel approxi-
mation, the 2-pyridinecarboxaldehyde was examined for its abil-
ity to modify IRMOF-3 and generated a new functionalized MOF
Figure 1. X-Ray powder patterns of IRMOF-3, IRMOF-3-PC and IRMOF-3-
PC-CuI.
wileyonlinelibrary.com/journal/aoc
Copyright © 2014 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. 2014, 28, 198–203

IRMOF-3-PC-Cu as catalyst for the synthesis of 2-aminobenzothiazoles
to 2.4% of the ―NH2 groups had been functionalized (see supporting
information for details).
With this promising result in hand, we started to investigate
the scope of this reaction under the optimized conditions. Inter-
estingly, the reactions proceeded extraordinarily well with a
variety of substituted phenyl isothiocyanates bearing electron-
withdrawing groups (NO2, CF3, MeO and Cl), with 2-iodoaniline
giving high yields (Table 2, entries 2–5). Electron-rich functional
groups in the para and meta position to phenyl isothiocyanate
were also well tolerated in these reactions. Reactions between
2-iodoaniline and a variety of phenyl isothiocyanates substituted
with electron-donating groups (4-Me, 3-Me, and 4-OMe) gave the
products in good yields (Table 2, entries 6–8). Notably, the
sterically hindered phenyl isothiocyanate, bearing an electron-
donating group, also proceeded smoothly, affording the product
in moderate yield (Table 2, entry 9).
Subsequently, the influence of the substituent group at the
2-iodoaniline was also examined. The reactions of 2-iodoaniline
with substituted groups, such as fluoro, and trifluoromethyl
groups on the benzene rings with various substituted
isothiocyanates, afforded the corresponding products in good
yields (Table 2, entries 10–17). Notably, the substituents at the
different positions of the benzene segment obviously affect
The structure of supported copper catalyst was also verified by
X-ray photoelectron spectroscopy (XPS) determination. The elec-
tron binding energy analysis indicated that the state of copper in
freshly prepared catalyst was as Cu(I) (supporting information,
Fig. IV).[19] However, the state of copper in used catalyst was
mainly as Cu(I), which could be coordinated with N-ligands.
We decided to test the modified MOF material, IRMOF-3-PC-CuI,
on the copper(I)-catalyzed synthesis of 2-aminobenzothiazoles via
the reaction of 2-iodoanilines with isothiocyanates. This tandem
cyclization was commonly carried out using Phen-CuI catalyst
system and 2.0 equiv. DABCO as a base in toluene.[16d] First, various
solvents and bases were examined at 60°C. The tandem reaction of
2-iodophenylamine and phenyl isothiocyanate was chosen as a
model reaction. As shown in Table 1, it is evident that high yields
were obtained when the reaction was performed in toluene, DMF
and 1,4-dioxane (Table 1, entries 1–3), whereas THF, 1,2 dichloro-
ethane (DCE) and acetonitrile afforded moderate yields (Table 1,
entries 4–6). Among the bases examined, it turned out that DABCO
acted as an excellent base and triethylamine afforded moderate
yields (Table 1, entry 7). However, inorganic bases such as Cs2CO3
and K3PO4, K2CO3 were substantially less effective (Table 1, entries
9–11). The amount of supported copper catalyst was also screened,
and 1.25 mol% loading of copper was found to be optimal (Table 1,
entries 1, 12 and 13).
Table 2. IRMOF-3-PC-CuI-catalyzed reactions of 2-iodoanilines with
isothiocyanatesa
R2
Table 1. Condition screening for the reaction of 2-iodoaniline with
phenyl isothiocyanatea
IRMOF-
NH
3-PC-CuI
NCS
DABCO,
toluene
IRMOF-
N
S
NH2
3-PC-CuI
R1
+
I
NH
NCS
base,
NH2
R2
N
S
solvent
2
1
R1
3
+
I
Entry
R1
R2
Product
Yield (%)b
Entry
Base
Solvent
Yield (%)b
1
H
H
3a
3b
3c
3d
3e
3f
94
90
88
60
80
93
82
95
65
86
95
93
92
80
74
66
63
61
1
DABCO
DABCO
DABCO
DABCO
DABCO
DABCO
Et3N
Toluene
DMF
94
70
2
H
H
H
H
H
H
H
H
4-Cl
2
3
4-NO2
2,5-MeO
3,5-CF3
4-CH3
3-CH3
4-MeO
2-CH3
H
3
DCE
32
4
4
CH3CN
THF
51
5
5
47
6
6
1,4-Dioxane
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
65
7
3g
3h
3i
7
73
8
8
DBU
42
9
9
Cs2CO3
K3PO4
Trace
Trace
Trace
76
10
11
12
13
14
15
16
17
18
4-F
4-F
4-F
4-F
4-F
3j
10
11
12c
13d
4-CH3
4-MeO
4-NO2
4-Cl
3k
3l
K2CO3
DABCO
DABCO
3m
3n
3o
3p
3q
3r
95
4-CF3
4-CF3
4-CF3
2,4-Cl
H
aReaction conditions: 2-iodoaniline (0.20 mmol), phenyl isothiocyanate
(0.22 mmol), IRMOF-3-PC-CuI (30mg, containing Cu 0.0025mmol),
base (0.40 mmol), solvent (1.0 ml), 60°C, N2 for 24 h.
4-CH3
4-Cl
bIsolated yields.
H
cIn the presence of IRMOF-3-PC-CuI (15 mg, containing Cu
0.00125 mmol).
aReaction conditions: 2-iodoaniline (0.20 mmol), isothiocyanate
(0.22mmol), IRMOF-3-PC-CuI (30 mg, containing Cu 0.0025 mmol),
and DABCO (0.40 mmol), toluene (1.0ml), 60°C, N2 for 24 h.
bIsolated yields.
dIn the presence of IRMOF-3-PC-CuI (60 mg, containing Cu
0.005 mmol).
Appl. Organometal. Chem. 2014, 28, 198–203
Copyright © 2014 John Wiley & Sons, Ltd.
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J. Liu et al.
Table 3. Successive runs by using recovered IRMOF-3-PC-CuI catalysta
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I
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Yield (%)b
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Acknowledgements
We gratefully acknowledge financial support by the National
Natural Science Foundation of China (Nos. 21172092, 20972057).
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Appl. Organometal. Chem. 2014, 28, 198–203
Copyright © 2014 John Wiley & Sons, Ltd.
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