An efficient heterogeneous cross-coupling of aryl iodides with diphenylphosphine catalyzed by copper (I) immobilized in MCM-41

Article abstract of DOI:10.1002/aoc.4417

The heterogeneous cross-coupling reaction of aryl iodides with diphenylphosphine was achieved in toluene at 115?°C in the presence of 10?mol% of phenanthroline-functionalized MCM-41-supported copper (I) complex (Phen-MCM-41-CuI) with Cs₂CO₃ as base, yielding various unsymmetric triarylphosphines in good to excellent yields. This protocol can tolerate a wide range of functional groups and does not need the use of expensive additives or harsh reaction conditions. This heterogeneous Cu (I) catalyst exhibited the same catalytic activity as homogeneous CuI/Phen system, and could easily be recovered by a simple filtration of the reaction solution and recycled up to seven times without significant loss of activity.

Full text of DOI:10.1002/aoc.4417

Received: 26 February 2018
DOI: 10.1002/aoc.4417
Revised: 13 April 2018
Accepted: 14 April 2018
F U L L P A P E R
An efficient heterogeneous cross‐coupling of aryl iodides
with diphenylphosphine catalyzed by copper (I)
immobilized in MCM‐41
Zhiqiang Fang1 | Mingzhong Cai2
| Yang Lin1 | Hong Zhao1
1 School of Chemistry and Chemical
The heterogeneous cross‐coupling reaction of aryl iodides with
diphenylphosphine was achieved in toluene at 115 °C in the presence of
10 mol% of phenanthroline‐functionalized MCM‐41‐supported copper (I) com-
plex (Phen‐MCM‐41‐CuI) with Cs2CO3 as base, yielding various unsymmetric
triarylphosphines in good to excellent yields. This protocol can tolerate a wide
range of functional groups and does not need the use of expensive additives or
harsh reaction conditions. This heterogeneous Cu (I) catalyst exhibited the
same catalytic activity as homogeneous CuI/Phen system, and could easily be
recovered by a simple filtration of the reaction solution and recycled up to
seven times without significant loss of activity.
Engineering, Guangdong Cosmetics
Engineering and Technology Research
Center, Guangdong Pharmaceutical
University, Guangzhou 510006, People's
Republic of China
2 College of Chemistry and Chemical
Engineering, Jiangxi Normal University,
Nanchang 330022, People's Republic of
China
Correspondence
Mingzhong Cai, College of Chemistry and
Chemical Engineering, Jiangxi Normal
University, Nanchang 330022, China.
Email: caimzhong@163.com
KEYWORDS
cross‐coupling, heterogeneous catalysis, phenanthroline copper complex, supported copper catalyst,
Hong Zhao, School of Chemistry and
Chemical Engineering, Guangdong
Cosmetics Engineering and Technology
Research Center, Guangdong
triarylphosphine
Pharmaceutical University, Guangzhou
510006, China.
Email: zhaohong1001@sina.com
Funding information
National Natural Science Foundation of
China, Grant/Award Number: 21272044;
Project of Innovation for Enhancing
Guangdong Pharmaceutical University;
Provincial Experimental Teaching Dem-
onstration Center of Chemistry and
Chemical Engineering
1 | INTRODUCTION
with a wide range of functional groups.[1] Among various
approaches for the preparation of arylphosphine ligands,
Tertiary arylphosphines as some of the most useful
ligands have widely been applied in transition‐metal‐cata-
lyzed reactions.[1] In addition, triarylphosphines are used
as catalysts[2] and fundamental building blocks[3] in
organic synthesis. The classical routes to arylphosphines
involve reactions of phosphine halides with aryl Grignard
or aryl lithium reagents, and are therefore incompatible
direct C─ P bond formation via transition‐metal‐catalyzed
coupling of aryl halides/triflates with unprotected second-
ary phosphines has been shown to be one of the most
valuable and highly efficient methods because this one‐
pot route does not require introduction of protecting
groups at phosphorus and is tolerant of a wide variety of
functional groups. Since the first palladium‐catalyzed
Appl Organometal Chem. 2018;e4417.
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Copyright © 2018 John Wiley & Sons, Ltd.
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https://doi.org/10.1002/aoc.4417

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FANG ET AL.
C─ P coupling of aryl halides with diarylphosphines was
reported by Stelzer and co‐workers,[4] the development
of palladium‐catalyzed,[5] copper‐catalyzed[6] and nickel‐
catalyzed[7] phosphinations of aryl halides or aryl triflates
for construction of tertiary phosphines has attracted con-
siderable interest. Recently, catalytic reduction of tertiary
phosphine oxides has also proven to be an alternative
route to tertiary phosphines.[8]
as highly efficient and recyclable catalysts. In order to
further expand our Cu (I)–MCM‐41 chemistry
toolbox,[12c,d,15c,d,16,22] herein we report the synthesis of
phenanthroline‐functionalized MCM‐41‐supported cop-
per (I) complexes and their catalytic efficiency in the
cross‐coupling of aryl iodides with diphenylphosphine.
Despite significant progress made in homogeneous
Pd‐, Cu‐ and Ni‐catalyzed construction of triarylphos-
phines, the use of expensive palladium complexes as well
as difficult recovery and non‐recyclability of the metal
catalysts make these methods of limited synthetic utility
from economic and environmental points of view. In
addition, homogeneous metal catalysis might cause heavy
metal contamination of the desired isolated product since
triarylphosphines could coordinate with palladium, cop-
per and nickel to form the corresponding complexes.[9]
Recycling of homogeneous metal catalysts is a task of
great importance economically and environmentally in
both the chemical and pharmaceutical industries, espe-
cially when expensive and/or toxic heavy metal catalysts
are utilized.[10] An attractive solution to these problems
is the substitution of homogeneous metal catalysts with
their heterogeneous counterparts.[11] In recent years, het-
erogeneous copper catalysts have been successfully
applied in carbon–carbon,[12] carbon–oxygen,[13] carbon–
nitrogen,[14] carbon–sulfur[15] and carbon–selenium[16]
bond formation reactions. However, to the best of
our knowledge, no examples of heterogeneous copper‐
catalyzed C─ P bond construction have been described
until now.
2 | RESULTS AND DISCUSSION
A series of phenanthroline‐functionalized MCM‐41‐sup-
ported copper (I) complexes (Phen‐MCM‐41‐CuX) were
prepared according to the procedure shown in Scheme 1.
First, MCM‐41 was condensed with 1‐(1,10‐
phenanthrolin‐5‐yl)‐3‐(3‐(triethoxysilyl)propyl)urea
in
toluene, followed by silylation with Me3SiCl to generate
the phenanthroline‐functionalized MCM‐41 (Phen‐
MCM‐41). The latter was then reacted with CuX in ace-
tone to afford a series of Phen‐MCM‐41‐CuX complexes
as light green powders.
Phen‐MCM‐41‐CuI was characterized using powder
X‐ray diffraction (XRD), nitrogen adsorption–desorption
measurements and energy‐dispersive X‐ray spectroscopy
(EDS). Figure 1 shows XRD patterns of the parent
MCM‐41 and Phen‐MCM‐41‐CuI. Compared with diffrac-
tion pattern of the parent MCM‐41, the (100) reflection of
Phen‐MCM‐41‐CuI was observed with decreased inten-
sity after grafting the copper complex, while the (110)
and (200) reflections became weak and diffuse, which
may be caused by contrast matching between the silicate
framework and organic moieties located inside the chan-
nels of MCM‐41. These results indicate that the ordered
mesoporous structure of the parent MCM‐41 remains
intact through the grafting procedure.
Mesoporous MCM‐41 materials have recently been
shown to be powerful supports for homogeneous metal
catalysts.[17] Some palladium,[18] rhodium,[19] molybde-
num,[20] gold[21] and copper[22] complexes have been
grafted on MCM‐41 and the resulting MCM‐41‐supported
metal complexes have been applied in organic synthesis
The nitrogen adsorption–desorption isotherms and
pore size distributions for MCM‐41 and Phen‐MCM‐41‐
CuI are presented in Figures 2 and 3, respectively. As
expected, the isotherms in Figure 2 have marked changes
SCHEME 1 Preparation of Phen‐MCM‐41‐CuX complexes

FANG ET AL.
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before and after grafting because of the introduction of
organic moieties into the channels of MCM‐41, but both
samples showed type IV isotherms. As shown in
Figure 3, the pore volume and size of Phen‐MCM‐41‐
CuI reduced significantly compared with those of MCM‐
41, also indicating that the organic moieties were
introduced into the inner channels, but the pores still
retained a narrow distribution. After grafting of the
phenanthroline–copper (I) complex onto MCM‐41, the
surface area and pore diameter decreased from 904
m2 g−1 and 2.7 nm to 567 m2 g−1 and 2.3 nm, respectively.
The EDS analysis shows the elements present in the
material. EDS analysis of fresh Phen‐MCM‐41‐CuI com-
plex shows the presence of Si, O, C, N, I and Cu elements
(Figure 4).
In our initial screening experiments, the reaction of
diphenylphosphine with 4‐iodoanisole was investigated
to optimize the reaction conditions, and the results are
summarized in Table 1. First, the effect of various
immobilized copper complexes on the model reaction
was examined using Cs2CO3 as base and toluene as
solvent at 115 °C (Table 1, entries 1–5). Among several
heterogeneous copper catalysts tested, we found that
Phen‐MCM‐41‐CuI (C) was the most efficient and gave
the desired 2a in 86% yield (Table 1, entry 3), while other
copper catalysts Phen‐MCM‐41‐CuCl (A), Phen‐MCM‐41‐
CuBr (B), Phen‐MCM‐41‐CuOTf (D) and Phen‐MCM‐41‐
CuCN (E) were substantially less effective and afforded
lower yields (Table 1, entries 1, 2, 4 and 5). Our next stud-
ies focused on the effect of bases on the model reaction,
with a significant base effect being observed (Table 1,
entries 3, 6–12). It was found that K2CO3 and K3PO4 were
also effective bases and gave good yields, whilst NaOMe,
NaOBu‐t, KOBu‐t and NaOAc were less effective and
n‐Bu3N was ineffective. So Cs2CO3 was the best choice.
When diglyme, dimethylformamide (DMF) and dioxane
were used as solvents instead of toluene, low yields were
obtained (Table 1, entries 13–15). Lowering the reaction
temperature to 105 or 95 °C resulted in a decreased yield
(Table 1, entries 16 and 17). When a homogeneous CuI/
Phen system was used as the catalyst, the desired product
2a was also isolated in 87% yield (Table 1, entry 18), indi-
cating that the catalytic activity of the Phen‐MCM‐41‐CuI
complex was comparable to that of CuI/Phen combina-
tion. Finally, the amount of the supported copper catalyst
was screened, and 10 mol% loading of copper was found
to be optimal. A lower yield was observed and a longer
reaction time was required when the amount of the
catalyst was decreased to 5 mol% (Table 1, entry 19).
Increasing the amount of the copper catalyst could
shorten the reaction time, but did not improve the yield
of 2a significantly (Table 1, entry 20). Therefore, the opti-
mal catalytic system involved the use of C (10 mol%),
FIGURE 1 XRD patterns of parent MCM‐41 (1) and Phen‐MCM‐
41‐CuI (2)
FIGURE 2 Nitrogen adsorption–desorption isotherms of MCM‐
41 and Phen‐MCM‐41‐CuI
FIGURE 3 Pore size distributions of MCM‐41 and Phen‐MCM‐
41‐CuI

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FANG ET AL.
FIGURE 4 EDS analysis of Phen‐
MCM‐41‐CuI complex
TABLE 1 Screening of reaction conditions for cross‐coupling of 4‐iodoanisole with diphenylphosphinea
Entry
Copper catalyst
Base
Solvent
Time (h)
Yield (%)b
1
A
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
K2CO3
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Diglyme
DMF
24
24
24
24
24
24
24
24
24
24
24
36
24
24
24
36
48
24
48
14
56
32
86
40
34
81
78
59
53
27
41
0
2
B
3
C
4
D
5
E
6
C
7
C
K3PO4
8
C
NaOMe
NaOBu‐t
KOBu‐t
NaOAc
n‐Bu3N
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
9
C
10
11
12
13
14
15
16c
17d
18
19e
20f
C
C
C
C
73
62
38
69
46
87
76
87
C
C
Dioxane
Toluene
Toluene
Toluene
Toluene
Toluene
C
C
CuI/Phen
C
C
aReaction was performed with 1a (1.0 mmol), Ph2PH (1.2 mmol), base (1.5 mmol) and copper catalyst (0.10 mmol) in solvent (3 ml) at 115 °C under argon.
bIsolated yield based on 1a.
cReaction at 105 °C.
dReaction at 95 °C.
e5 mol% Phen‐MCM‐41‐CuI was used.
f20 mol% Phen‐MCM‐41‐CuI was used.

FANG ET AL.
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TABLE 2 Heterogeneous copper‐catalyzed synthesis of unsymmetric triarylphosphines via C─ P coupling of aryl iodides with Ph2PHa
aReaction was performed with 1 (1.0 mmol), Ph2PH (1.2 mmol), Cs2CO3 (1.5 mmol) and Phen‐MCM‐41‐CuI (10 mol%) in toluene (3 ml) at 115 °C under argon
for 24 h. Isolated yields are given based on 1.
Cs2CO3 as base in toluene at 115 °C under argon for 24 h
(Table 1, entry 3).
in 74–89% yields. 3‐Chloro‐4‐methyliodobenzene (1q)
also gave the desired 2q in 83% yield. These results indi-
cate that the electronic nature of the substituents on the
benzene ring has limited influence on the heterogeneous
copper‐catalyzed C─ P coupling reaction. Base‐sensitive
functional groups such as methyl ketone (1 l) and esters
(1o, 1p) are tolerated by this method. In addition,
sterically hindered o‐substituted aryl iodides such as
With the optimal reaction conditions established, we
next examined the scope and limitations of this heteroge-
neous copper‐catalyzed C─ P coupling reaction. The
results are summarized in Table 2. The C─ P coupling
reactions of electron‐neutral, electron‐rich and electron‐
deficient aryl iodides 1b–x with Ph2PH proceeded
smoothly under the optimized conditions to afford the
corresponding unsymmetric triarylphosphines 2b–x in
good to excellent yields. For example, reaction of
iodobenzene 1b with Ph2PH gave triphenylphosphine
2b in 90% yield. The electron‐rich aryl iodides 1c–e
showed a reactivity similar to that of 4‐iodoanisole (1a)
and afforded the desired products 2c–e in 78–87% yields.
3,5‐Dimethyliodobenzene (1f) and 4‐iodobiphenyl (1 g)
also proved to be good coupling partners and produced
the expected triarylphosphines 2f and 2 g in good yields.
For electron‐deficient aryl iodides bearing either weak
electron‐withdrawing groups such as fluoro, bromo and
chloro (1 h–j) or strong electron‐withdrawing groups
such as trifluoromethyl, acetyl, cyano, nitro and ester
(1 k–p), the C─ P coupling reactions also proceeded effec-
tively to give the corresponding triarylphosphines 2 h–p
2‐iodotoluene
(1r),
2‐iodoanisole
(1
s),
2‐
chloroiodobenzene (1 t), 2‐iodobiphenyl (1u), methyl
2‐iodobenzoate (1v) and 2,4‐difluoroiodobenzene (1w)
could undergo the C─ P coupling reaction effectively to
furnish the desired coupling products 2r–w in 64–76%
yields. Even if highly sterically hindered 2,4,6‐
trimethyliodobenzene (1x) was used as substrate, the
expected product 2x was also isolated in 65% yield. It is
noteworthy that the bulky 1‐iodonaphthalene 1y was suc-
cessfully coupled to diphenylphosphine to give 2y in excel-
lent yield. Heteroatoms turned out to be compatible with
the employed reaction conditions, the reactions of
2‐iodothiophene (1z), 2‐iodopyridine (1a′) and 2‐fluoro‐3‐
iodopyridine (1b′) with diphenylphosphine affording the
corresponding products 2z–b′in good yields. Encouraged
by these results, we also carried out the reaction

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FANG ET AL.
of bromobenzene with diphenylphosphine under the same
conditions; unfortunately, only a trace of the desired prod-
uct 2b was detected, so 4‐bromoiodobenzene (1j) was selec-
tively subjected to the coupling reaction to produce the
desired product 2j in high yield. Even if electron‐deficient
aryl bromides such as 4‐nitrobromobenzene and
4‐bromobenzonitrile were used as substrates, the yields of
the desired products were very low (<10%). The present
method provides a quite general and practical route for
carried out until an approximately 50% conversion of
1a. Then Phen‐MCM‐41‐CuI was removed by filtration
of the reaction mixture at 115 °C and the filtrate was
allowed to react further at 115 °C under argon. In this
case, no increase in conversion of 1a was observed, indi-
cating that leached copper species from Phen‐MCM‐41‐
CuI (if any) are not responsible for the observed activity.
We also determined the copper content in the filtrate
using inductively coupled plasma atomic emission spec-
troscopy (ICP‐AES), and no copper was detected in the
solution. These results demonstrated that the catalyst
was stable during the C─ P coupling reaction and the
observed catalysis was intrinsically heterogeneous.
the synthesis of
a wide variety of unsymmetric
triarylphosphines having various functionalities.
To confirm that the high activity of Phen‐MCM‐41‐
CuI results from the copper sites on the channel walls
and not from leached copper species, the heterogeneity
of Phen‐MCM‐41‐CuI was tested by hot filtration.[23]
The reaction of 4‐iodoanisole (1a) with Ph2PH was
A
plausible mechanism for the heterogeneous
copper (I)‐catalyzed cross‐coupling reaction of
diphenylphosphine with aryl iodides (1) is illustrated in
Scheme 2. Firstly, oxidative addition of Ar─ I (1) to
Phen‐MCM‐41‐CuI gives an MCM‐41‐immobilized 1,10‐
phenanthroline–ArCu (III)I2 intermediate A.[24] The lat-
ter subsequently reacts with diphenylphosphine in the
presence of Cs2CO3 to afford an MCM‐41‐immobilized
1,10‐phenanthroline–ArCu (III)I–PPh2 intermediate B.
Finally, reductive elimination of intermediate B produces
the desired triarylphosphine 2 and regenerates the Phen‐
MCM‐41‐CuI complex to complete the catalytic cycle.
Under the optimized conditions, the stability and
recyclability of Phen‐MCM‐41‐CuI were evaluated in
the reaction between 1‐iodonaphthalene and diphenyl-
phosphine. The results are summarized in Table 3. Filtra-
tion of the crude mixture followed by washing of the
resulting solid with distilled water and acetone allowed
the easy recovery of Phen‐MCM‐41‐CuI. The recovered
catalyst could be recycled up to seven times, and almost
the same yield of 2y was observed. In addition, ICP‐AES
analysis was conducted on the recovered catalyst after
eight consecutive runs. The copper content was found to
be 0.73 mmol g−1, revealing almost the same copper
content as for the fresh catalyst.
SCHEME
2
Plausible mechanism for heterogeneous Cu‐
catalyzed C─ P coupling reaction
TABLE 3 Recycling of Phen‐MCM‐41‐CuIa
Entry
Catalyst cycle
Time (h)
Yield (%)b
Entry
Catalyst cycle
Time (h)
Yield (%)b
1
2
3
4
1st (fresh)
2nd
24
24
24
24
92
91
92
90
5
6
7
8
5th
6th
7th
8th
24
24
26
28
91
91
90
89
3rd
4th
aReaction was performed with 1y (5.0 mmol), Ph2PH (6.0 mmol), Cs2CO3 (7.5 mmol) and Phen‐MCM‐41‐CuI (0.50 mmol) in toluene (10 ml) at 115 °C under
argon.
bIsolated yield based on 1y.

FANG ET AL.
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and washed with CHCl3 (20 ml), and dried under vacuum
at 150 °C for 6 h. The solid was then soaked in a solution
of 4.5 g of Me3SiCl in 70 ml of dry toluene at 25 °C with
stirring for 24 h. The product was filtered, washed with
acetone (3 × 20 ml) and Et2O (3 × 20 ml), and dried
under vacuum at 110 °C for 6 h to afford 1.54 g of hybrid
material Phen‐MCM‐41. The nitrogen content was deter-
mined to be 3.67 mmol g−1 using elemental analysis.
3 | CONCLUSIONS
In summary, we have developed a novel, practical and
environmentally friendly route to unsymmetric triaryl-
phosphines through cross‐coupling reactions of aryl
iodides with diphenylphosphine using Phen‐MCM‐41‐
CuI as catalyst. This new heterogeneous copper catalyst
could be prepared by a simple procedure from commer-
cially available and inexpensive reagents and exhibited
the same catalytic activity as the homogeneous CuI/Phen
system. The reactions generated a variety of unsymmetric
triarylphosphines in good to excellent yields and tolerated
a wide range of functional groups, including base‐sensi-
tive groups. In addition, this methodology offers the com-
petitiveness of recyclability of the copper catalyst without
significant decreases in activity, and the copper catalyst
can be recovered by simple filtration and recycled up to
seven times, thus making this procedure economically
and environmentally more acceptable.
4.2 | Synthesis of Phen‐MCM‐41‐CuI (C)
In a small Schlenk tube, 1.22 g of Phen‐MCM‐41 was
mixed with 0.215 g (1.1 mmol) of CuI in 25 ml of dry ace-
tone. The reaction mixture was stirred at 60 °C for 24 h
under argon. The resulting product was filtered by suc-
tion, washed with distilled water and acetone, and dried
at 80 °C under vacuum for 6 h to afford 1.32 g of a light
green copper complex (Phen‐MCM‐41‐CuI). The nitrogen
and copper contents were determined to be 3.42 and
0.74 mmol g−1, respectively.
Phen‐MCM‐41‐CuCl (A), Phen‐MCM‐41‐CuBr (B),
Phen‐MCM‐41‐CuOTf (D) and Phen‐MCM‐41‐CuCN (E)
were also prepared using Phen‐MCM‐41 (1.2 g) and
1.1 mmol of CuX (X = Cl, Br, OTf, CN) as the starting
materials in the same manner. The copper contents were
4 | EXPERIMENTAL
All chemicals were of reagent grade and used as pur-
chased, unless otherwise noted. The mesoporous material
MCM‐41[17b]
and
1‐(1,10‐phenanthrolin‐5‐yl)‐3‐(3‐
determined to be 0.73, 0.71, 0.70 and 0.66 mmol g−1
respectively.
,
(triethoxysilyl)propyl)urea[25] were prepared according
to literature procedures. All reactions were performed in
dried solvent under an inert atmosphere of argon. The
products were purified by flash chromatography on silica
gel. A mixture of CH2Cl2 and hexane was generally used
4.3 | General Procedure for Cross‐
Coupling of Diphenylphosphine with
Various Aryl Iodides
1
as eluent. H NMR spectra were recorded using a Bruker
Avance 400 MHz spectrometer with tetramethylsilane as
an internal standard in CDCl3 as solvent. 13C NMR spec-
tra (100 MHz) were recorded with a Bruker Avance
400 MHz spectrometer in CDCl3 as solvent. 31P NMR
spectra (121 MHz) were recorded with a Bruker Avance
400 MHz spectrometer in CDCl3 as solvent. Melting
points are uncorrected. Copper content was determined
with ICP‐AES (Atomscan16, TJA Corporation). Powder
XRD patterns were obtained with a Damx‐rA (Rigaku).
Nitrogen adsorption–desorption isotherms were obtained
using a Belsorp‐HP (Bel Japan Inc.) at 77 K. Prior to gas
adsorption measurements, materials were degassed for
6 h at 423 K. EDS was performed using a microscope.
Phen‐MCM‐41‐CuI (135 mg, 0.1 mmol), Cs2CO3
(1.5 mmol) and aryl iodide 1 (1.0 mmol) (if solid) were
placed in an oven‐dried 20 ml Schlenk tube, and the reac-
tion vessel was evacuated and filled with argon three
times. Then 1 (1.0 mmol) (if liquid), diphenylphosphine
(1.2 mmol) and toluene (3 ml) were added with a syringe
under a counter flow of argon. The vessel was sealed with
a screw cap, stirred at room temperature for 10 min and
then connected to the Schlenk line filled with argon.
The reaction mixture was stirred at 115 °C for 24 h. Upon
completion of the reaction, the mixture was cooled to
room temperature and diluted with CH2Cl2 (20 ml) and
filtered. The Phen‐MCM‐41‐CuI complex was washed
with distilled water (2 × 5 ml) and acetone (2 × 5 ml),
and reused in the next run. The filtrate was concentrated
in vacuo and the residue was purified by flash column
chromatography on silica gel to provide the product 2.
Diphenyl (4‐methoxyphenyl) phosphine (2a).[6b]
4.1 | Preparation of Phen‐MCM‐41
To a suspension of 1.12 g of MCM‐41 in 100 ml of dry tol-
uene was added a solution of 1.48 g of 1‐(1,10‐
1
phenanthrolin‐5‐yl)‐3‐(3‐(triethoxysilyl)propyl)urea
in
White solid; m.p. 67–68 °C. H NMR (400 MHz, CDCl3,
10 ml of dry toluene. The reaction mixture was stirred
at reflux under argon for 24 h. Then the solid was filtered
δ, ppm): 7.25–7.16 (m, 12H), 6.82 (d, J = 8.0 Hz, 2H),
3.73 (s, 3H). 31P NMR (121 MHz, CDCl3, δ, ppm): −7.10 (s).

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FANG ET AL.
Triphenylphosphine (2b).[6b] White solid; m.p. 79–
Methyl 4‐(diphenylphosphino) benzoate (2o).[6b]
White solid; m.p. 103–104 °C. 1H NMR (400 MHz, CDCl3,
δ, ppm): 7.97 (d, J = 7.2 Hz, 2H), 7.41–7.28 (m, 12H), 3.91
(s, 3H). 31P NMR (121 MHz, CDCl3, δ, ppm): −5.05 (s).
Ethyl 4‐(diphenylphosphino) benzoate (2p).[30] White
solid; m.p. 83–84 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.98 (d, J = 8.4 Hz, 2H), 7.42–7.24 (m, 12H), 4.36
(q, J = 7.2 Hz, 2H), 1.37 (t, J = 7.2 Hz, 3H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −5.07 (s).
1
80 °C. H NMR (400 MHz, CDCl3, δ, ppm): 7.44–7.23
(m, 15H). 31P NMR (121 MHz, CDCl3, δ, ppm): −5.45 (s).
Diphenyl (4‐methylphenyl) phosphine (2c).[6b] White
solid; m.p. 68–69 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.37–7.14 (m, 14H), 2.34 (s, 3H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −6.30 (s).
Diphenyl (3‐methylphenyl) phosphine (2d).[26] White
solid; m.p. 50–51 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.42–7.06 (m, 14H), 2.30 (s, 3H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −5.23 (s).
Diphenyl (3‐chloro‐4‐methylphenyl) phosphine (2q).
1
Colorless oil. H NMR (400 MHz, CDCl3, δ, ppm): 7.35–
Diphenyl (4‐aminophenyl) phosphine (2e).[4a] White
solid; m.p. 37–38 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.23–7.12 (m, 10H), 7.06 (t, J = 7.6 Hz, 2H), 6.54
(d, J = 7.6 Hz, 2H), 3.43 (br, 2H). 31P NMR (121 MHz,
CDCl3, δ, ppm): −6.61 (s).
7.24 (m, 11H), 7.19 (d, J = 7.6 Hz, 1H), 7.11–7.06 (m,
1H), 2.36 (s, 3H). 31P NMR (121 MHz, CDCl3, δ, ppm):
−5.96 (s). Anal. Calcd for C19H16ClP (%): C, 73.43; H,
5.19. Found (%): C, 73.17; H, 4.91.
Diphenyl (2‐methylphenyl) phosphine (2r).[6b] White
solid; m.p. 65–66 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.35–7.21 (m, 12H), 7.15–7.04 (m, 1H), 6.79–6.73
(m, 1H), 2.39 (s, 3H). 31P NMR (121 MHz, CDCl3, δ,
ppm): −13.27 (s).
Diphenyl (3,5‐dimethylphenyl) phosphine (2f).[4a]
1
Colorless oil. H NMR (400 MHz, CDCl3, δ, ppm): 7.25–
7.12 (m, 10H), 6.89–6.83 (m, 3H), 2.16 (s, 6H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −5.28 (s).
4‐(Diphenylphosphino) biphenyl (2 g).[27] White solid;
Diphenyl (2‐methoxyphenyl) phosphine (2 s).[6b]
White solid; m.p. 122–123 °C. 1H NMR (400 MHz, CDCl3,
δ, ppm): 7.45–7.27 (m, 11H), 6.91–6.85 (m, 2H), 6.73–6.68
(m, 1H), 3.75 (s, 3H). 31P NMR (121 MHz, CDCl3, δ,
ppm): −16.61 (s).
1
m.p. 83–84 °C. H NMR (400 MHz, CDCl3, δ, ppm): 7.58
(t, J = 8.0 Hz, 4H), 7.45–7.32 (m, 15H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −5.99 (s).
Diphenyl (4‐fluorophenyl) phosphine (2 h).[28] White
solid; m.p. 53–54 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.35–7.24 (m, 12H), 7.03 (t, J = 8.6 Hz, 2H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −6.58 (d).
Diphenyl (2‐chlorophenyl) phosphine (2 t).[33] White
1
solid; m.p. 103–104 °C. H NMR (400 MHz, CDCl3, δ,
ppm): 7.34–7.15 (m, 12H), 7.06 (t, J = 7.4 Hz, 1H), 6.69–
6.65 (m, 1H). 31P NMR (121 MHz, CDCl3, δ, ppm): −10.87 (s).
2‐(Diphenylphosphino) biphenyl (2u).[34] White solid;
m.p. 60–61 °C. 1H NMR (400 MHz, CDCl3, δ, ppm): 7.33–
7.09 (m, 18H), 7.00–6.96 (m, 1H). 31P NMR (121 MHz,
CDCl3, δ, ppm): −13.33 (s).
Diphenyl (4‐chlorophenyl) phosphine (2i).[29] White
solid; m.p. 44–45 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.31–7.20 (m, 12H), 7.14 (t, J = 7.4 Hz, 2H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −6.48 (s).
Diphenyl (4‐bomophenyl) phosphine (2j).[29] White
solid; m.p. 78–79 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.45 (d, J = 7.6 Hz, 2H), 7.35–7.24 (m, 10H), 7.15
(t, J = 7.6 Hz, 2H). 31P NMR (121 MHz, CDCl3, δ,
ppm): −6.44 (s).
Methyl 2‐(diphenylphosphino) benzoate (2v).[29]
1
White solid; m.p. 97–98 °C. H NMR (400 MHz, CDCl3,
δ, ppm): 8.05 (d, J = 2.8 Hz, 1H), 7.38–7.23 (m, 12H),
6.94 (m, 1H), 3.73 (s, 3H). 31P NMR (121 MHz, CDCl3,
δ, ppm): −4.26 (s).
Diphenyl
(3‐trifluoromethylphenyl)
phosphine
(2 k).[30] Colorless oil. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.60–7.56 (m, 2H), 7.44–7.41 (m, 2H), 7.37–7.28
(m, 10H). 31P NMR (121 MHz, CDCl3, δ, ppm): −5.30 (s).
Diphenyl (4‐acetylphenyl) phosphine (2 l).[6b] White
Diphenyl (2,4‐difluorophenyl) phosphine (2w). Pale
1
yellow oil. H NMR (400 MHz, CDCl3, δ, ppm): 7.37–
7.26 (m, 10H), 6.85–6.75 (m, 3H). 31P NMR (121 MHz,
CDCl3, δ, ppm): −99.40 (m). Anal. Calcd for C18H13F2P
(%): C, 72.48; H, 4.39. Found (%): C, 72.26; H, 4.15.
Diphenyl (2,4,6‐trimethylphenyl) phosphine (2x). Col-
1
solid; m.p. 121–122 °C. H NMR (400 MHz, CDCl3, δ,
ppm): 7.80 (d, J = 7.2 Hz, 2H), 7.35–7.15 (m, 12H), 2.50
(s, 3H). 31P NMR (121 MHz, CDCl3, δ, ppm): −5.07 (s).
Diphenyl (4‐cyanophenyl) phosphine (2 m).[31] White
solid; m.p. 86–87 °C. 1H NMR (400 MHz, CDCl3, δ, ppm):
7.55 (dd, J = 8.4, 1.6 Hz, 2H), 7.38–7.29 (m, 12H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −4.46 (s).
1
orless oil. H NMR (400 MHz, CDCl3, δ, ppm): 7.27–7.22
(m, 4H), 7.20–7.11 (m, 6H), 6.81 (s, 2H), 2.19 (s, 3H), 2.09
(s, 6H). 31P NMR (121 MHz, CDCl3, δ, ppm): −16.52 (s).
Anal. Calcd for C21H21P (%): C, 82.87; H, 6.95. Found
(%): C, 82.59; H, 6.81.
Diphenyl (4‐nitrophenyl) phosphine (2n).[32] Yellow
1‐(Diphenylphosphino) naphthalene (2y).[6b] White
1
1
solid; m.p. 134–135 °C. H NMR (400 MHz, CDCl3, δ,
solid; m.p. 122–123 °C. H NMR (400 MHz, CDCl3, δ,
ppm): 8.14 (d, J = 7.6 Hz, 2H), 7.42–7.27 (m, 12H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −4.48 (s).
ppm): 7.87–7.82 (m, 2H), 7.49–7.23 (m, 15H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −14.13 (s).

FANG ET AL.
9 of 10
2‐(Diphenylphosphino) thiophene (2z).[6b] White
Eustache, Org. Lett. 2005, 7, 681. d) M. Kalek, J. Stawinski,
Organometallics 2007, 26, 5840. e) M. Kalek, A. Ziadi, J.
Stawinski, Org. Lett. 2008, 10, 4637. f) Y. Belabassi, S. Alzghari,
J. M. Montchamp, J. Organomet. Chem. 2008, 693, 3171. g) A.
Bessmertnykh, C. M. Douaihy, S. Muniappan, R. Guilard, Syn-
thesis 2008, 1575. h) M. Kalek, M. Jezowska, J. Stawinski, Adv.
Synth. Catal. 2009, 351, 3207. i) Y. Luo, J. Wu, Organometallics
2009, 28, 6823. j) D. Hockova, M. Dracinsky, A. Holy, Eur. J.
Org. Chem. 2010, 2885. k) E. L. Deal, C. Petit, J. L. Montchamp,
Org. Lett. 2011, 13, 3270. l) K. Xu, H. Hu, F. Yang, Y. J. Wu,
Eur. J. Org. Chem. 2013, 319.
solid; m.p. 44–45 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 7.58 (d, J = 3.2 Hz, 1H), 7.48–7.06 (m, 12H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −19.99 (s).
2‐(Diphenylphosphino) pyridine (2a′).[35] White solid;
1
m.p. 82–83 °C. H NMR (400 MHz, CDCl3, δ, ppm): 8.72
(d, J = 3.6 Hz, 1H), 7.57 (t, J = 7.6 Hz, 1H), 7.40–7.25 (m,
10H), 7.18 (t, J = 5.8 Hz, 1H), 7.08 (d, J = 8.0 Hz, 1H). 31P
NMR (121 MHz, CDCl3, δ, ppm): −4.06 (s).
3‐(Diphenylphosphino)‐2‐fluoropyridine (2b′). White
solid; m.p. 61–63 °C. 1H NMR (400 MHz, CDCl3, δ,
ppm): 8.18 (dd, J = 4.6, 1.0 Hz, 1H), 7.40–7.25 (m, 10H),
7.23–7.18 (m, 1H), 7.11–7.07 (m, 1H). 31P NMR
(121 MHz, CDCl3, δ, ppm): −58.33 (d). Anal. Calcd for
C17H13FNP (%): C, 72.59; H, 4.66; N, 4.98. Found (%): C,
[6] a) T. Ogawa, N. Usuki, N. Ono, J. Chem. Soc. Pekin Trans. 1998,
1, 2953. b) D. Van Allen, D. Venkataraman, J. Org. Chem. 2003,
68, 4590. c) D. Gelman, L. Jiang, S. L. Buchwald, Org. Lett.
2003, 5, 2315. d) H. H. Rao, Y. Jin, H. Fu, Y. Y. Jiang, Y. F.
Zhao, Chem. A Eur. J. 2006, 12, 3636. e) C. Huang, X. Tang,
Y. Y. Jiang, Y. F. Zhao, J. Org. Chem. 2006, 71, 5020.
1
72.33; H, 4.51; N, 4.75. Copies of H NMR and 31P NMR
[7] a) D. J. Ager, S. A. Laneman, Chem. Commun. 1997, 2359. b) F.
Y. Kwong, A. S. C. Chan, K. S. Chan, Tetrahedron 2000, 56,
8893. c) M. Jahjah, R. Jahjah, S. Pellet‐Rostaing, M. Lemaire,
Tetrahedron: Asymm. 2007, 18, 1224. d) J. Horn, W.
Bannwarth, Eur. J. Org. Chem. 2007, 2058. e) D. Marcoux, A.
B. Charette, Adv. Synth. Catal. 2008, 350, 2967. f) M. Sun, Y.‐
S. Zang, L.‐K. Hou, X.‐X. Chen, W. Sun, S.‐D. Yang, Eur. J.
Org. Chem. 2014, 6796. g) D. Cai, J. F. Payack, D. R. Bender,
D. L. Hughes, T. R. Verhoeven, P. J. Reider, J. Org. Chem.
1994, 59, 7180.
spectra of compounds 2a‐2b' have been provided in
Supporting Information section.
ACKNOWLEDGMENTS
We thank the National Natural Science Foundation of
China (project no. 21272044) and Project of Innovation
for Enhancing Guangdong Pharmaceutical University,
Provincial Experimental Teaching Demonstration Center
of Chemistry and Chemical Engineering for financial
support.
[8] a) Y. Li, S. Das, S. Zhou, K. Junge, M. Beller, J. Am. Chem. Soc.
2012, 134, 9727. b) Y. Li, L.‐Q. Lu, S. Das, S. Pisiewicz, K.
Junge, M. Beller, J. Am. Chem. Soc. 2012, 134, 18325. c) M.‐L.
Schirmer, S. Jopp, J. Holz, A. Spannenberg, T. Werner, Adv.
Synth. Catal. 2016, 358, 26. d) M. Kuroboshi, T. Kita, A. Aono,
T. Katagiri, S. Kikuchi, S. Yamane, H. Kawakubo, H. Tanaka,
Tetrahedron Lett. 2015, 56, 918.
ORCID
Mingzhong Cai http://orcid.org/0000-0002-1056-2846
[9] a) C. E. Garrett, K. Prasad, Adv. Synth. Catal. 2004, 346, 889. b)
C. J. Welch, J. Albaneze‐Walker, W. R. Leonard, M. Biba, J.
DaSilva, D. Henderson, B. Laing, D. J. Mathre, S. Spencer, X.
Bu, T. Wang, Org. Process Res. Dev. 2005, 9, 198.
REFERENCES
[1] a) G. M. Kosolapoff, L. Maier, Organic Phosphorus Compounds,
Vol. 1, 2nd ed., Wiley‐Interscience, New York 1972. b) Organo-
phosphorus Chemistry, Vol. 1–15, Royal Society of Chemistry,
London 1969–1983. c) I. P. Beletskaya, M. A. Kazankova, Russ.
J. Org. Chem. 2002, 38, 1391.
[10] D. J. Cole‐Hamilton, Science 2003, 299, 1702.
[11] For selected reviews, see: a) N. T. S. Phan, M. V. D. Sluys, C. W.
Jones, Adv. Synth. Catal. 2006, 348, 609. b) L. Yin, J. Liebscher,
Chem. Rev. 2007, 107, 133. c) R. Akiyama, S. Kobayashi, Chem.
Rev. 2009, 109, 594. d) M. J. Climent, A. Corma, S. Iborra,
Chem. Rev. 2011, 111, 1072. e) A. Molnar, Chem. Rev. 2011,
111, 2251. f) M. Yoon, R. Srirambalaji, K. Kim, Chem. Rev.
2012, 112, 1196.
[2] a) F. Zheng, T.‐F. Leung, K.‐W. Chan, H. H. Y. Sung, L. D. Wil-
liams, Z. Xie, G. Jia, Chem. Commun. 2016, 52, 10767. b) M.
Yang, T. Wang, S. Cao, Z. He, Chem. Commun. 2014, 50,
13506. c) U. P. N. Tran, K. J. Hock, C. P. Gordon, R. M.
Koenigs, T. V. Nguyen, Chem. Commun. 2017, 53, 4950. d)
H.‐W. Shin, J. A. Prescher, J. Am. Chem. Soc. 2015, 137, 10036.
[12] a) Q. Wu, L. Wang, Synthesis 2008, 2007. b) L. Zhang, P. Li, L.
Wang, Lett. Org. Chem. 2006, 3, 282. c) R. Xiao, R. Yao, M. Cai,
Eur. J. Org. Chem. 2012, 4178. d) H. Zhao, B. Huang, Y. Wu, M.
Cai, J. Organomet. Chem. 2015, 797, 21.
[3] a) F. K. Kwong, K. S. Chan, Organometallics 2000, 19, 2058. b)
H. Zhou, J. Li, H. Yang, C. Xia, G. Jiang, Org. Lett. 2015, 17,
4628.
[4] a) O. Herd, A. Hessler, M. Hingst, M. Trepper, O. Stelzer,
J. Organomet. Chem. 1996, 522, 69. b) P. Machnitzki, T. Nickel,
O. Stelzer, C. Landgrafe, Eur. J. Inorg. Chem. 1998, 1029.
[13] a) G. C. H. Chiang, T. Olsson, Org. Lett. 2004, 6, 3079. b) T.
Miao, L. Wang, Tetrahedron Lett. 2007, 48, 95. c) S. Benyahya,
F. Monnier, M. Taillefer, M. W. Chi Man, C. Bied, F. Ouazzan,
Adv. Synth. Catal. 2008, 350, 2205. d) N. T. S. Phan, T. T.
Nguyen, V. T. Nguyen, K. D. Nguyen, CatChemCat 2013, 5,
2374.
[5] For selected examples, see: a) D. Gelman, L. Jiang, S. L.
Buchwald, Org. Lett. 2003, 5, 2315. b) L. J. Gooßen, M. K.
Dezfuli, Synlett 2005, 445. c) S. Thielges, P. Bisseret, J.

10 of 10
FANG ET AL.
[14] a) X. Xiong, L. Cai, Catal. Sci. Technol. 2013, 3, 1301. b) D.
Wang, L. Etienne, M. E. Igartua, S. Moya, D. Astruc, Chem. A
Eur. J. 2014, 20, 4047. c) G. Chouhan, D. Wang, H. Alper,
Chem. Commun. 2007, 4809. d) R. Xiao, H. Zhao, M. Cai, Tetra-
hedron 2013, 69, 5444. e) W. He, H. Zhao, R. Yao, M. Cai, RSC
Adv. 2014, 4, 50285.
[22] H. Zhao, W. He, L. Wei, M. Cai, Catal. Sci. Technol. 2016, 6,
1488.
[23] H. E. B. Lempers, R. A. Sheldon, J. Catal. 1998, 175, 62.
[24] A. Casitas, X. Ribas, Chem. Sci. 2013, 4, 2301.
[25] M.‐J. Li, Z. Chen, V. Wing‐Wah Yam, Y. Zu, ACS Nano 2008, 2,
905.
[15] a) J. Yang, P. Li, L. Wang, Tetrahedron 2011, 67, 5543. b) M.
Cai, R. Xiao, T. Yan, H. Zhao, J. Organomet. Chem. 2014, 749,
55. c) M. Cai, R. Yao, L. Chen, H. Zhao, J. Mol. Catal. A
2014, 395, 349. d) H. Zhao, W. He, R. Yao, M. Cai, Adv. Synth.
Catal. 2014, 356, 3092.
[26] E. A. Yakovleva, E. N. Tsvetkov, D. I. Lobanov, M. I.
Kabachnik, A. I. Shatenshtein, Tetrahedron Lett. 1966, 7, 4161.
[27] M. Joshaghani, E. Faramarzi, E. Rafiee, M. Daryanavard, J.
Xiao, C. Baillie, J. Mol. Catal. A: Chem. 2006, 259, 35.
[16] H. Zhao, Y. Jiang, Q. Chen, M. Cai, New J. Chem. 2015, 39,
[28] S. I. Pombrik, V. F. Ivanov, A. S. Peregudov, D. N. Kravtsov, A.
2106.
A. Fedorov, E. I. Fedin, J. Organomet. Chem. 1978, 153, 319.
[17] a) C. T. Kresge, M. E. Leonowicz, W. J. Roth, J. C. Vartuli, J. S.
Beck, Nature 1992, 359, 710. b) J. S. Beck, J. C. Vartuli, W. J.
Roth, M. E. Leonowicz, C. T. Kresge, K. D. Schmitt, C. T.‐W.
Chu, D. H. Olson, E. W. Sheppard, S. B. McCullen, J. B.
Higgins, J. L. Schlenker, J. Am. Chem. Soc. 1992, 114, 10834.
c) W. Zhou, J. M. Thomas, D. S. Shephard, B. F. G. Johnson,
D. Ozkaya, T. Maschmeyer, R. G. Bell, Q. Ge, Science 1998,
280, 705. d) A. Taguchi, F. Schuth, Micropor. Mesopor. Mater.
2005, 77, 1. e) R. M. Martin‐Aranda, J. Cejka, Top. Catal.
2010, 53, 141.
[29] S. E. Tunney, J. K. Stille, J. Org. Chem. 1987, 52, 748.
[30] E. L. Gall, M. Troupel, J.‐Y. Nedelec, Tetrahedron 2003, 59,
7497.
[31] F. Y. Kwong, C. W. Lai, M. Yu, K. S. Chan, Tetrahedron 2004,
60, 5635.
[32] G. P. Schiemenz, Eur. J. Inorg. Chem. 1966, 514.
[33] F. A. Hart, J. Chem. Soc. 1960, 3324.
[34] E. Rafler, D. G. Gilheany, J. N. H. Reek, P. W. N. M. van
Leeuwen, ChemCatChem 2010, 2, 387.
[18] For selected examples, see: a) P. C. Mehnert, D. W. Weaver, J. Y.
Ying, J. Am. Chem. Soc. 1998, 120, 12289. b) K. Mukhopadhyay,
B. R. Sarkar, R. V. Chaudhari, J. Am. Chem. Soc. 2002, 124, 9692.
c) J. Y. Ying, C. P. Mehnert, M. S. Wong, Angew. Chem. Int. Ed.
1999, 38, 56. d) M. Cai, G. Zheng, G. Ding, Green Chem. 2009, 11,
1687. e) M. Cai, J. Peng, W. Hao, G. Ding, Green Chem. 2011, 13,
190. f) W. Hao, H. Liu, L. Yin, M. Cai, J. Org. Chem. 2016, 81,
4244. g) F. Havasi, A. Ghorbani‐Choghamarani, F. Nikpour,
New J. Chem. 2015, 39, 6504.
[35] F. G. Mann, J. Watson, J. Org. Chem. 1948, 13, 502.
SUPPORTING INFORMATION
Additional supporting information may be found online
in the Supporting Information section at the end of the
article.
[19] a) S.‐G. Shyu, S.‐W. Cheng, D.‐L. Tzou, Chem. Commun. 1999,
2337. b) Y. Yang, R. M. Rioux, Chem. Commun. 2011, 47, 6557.
How to cite this article: Fang Z, Cai M, Lin Y,
Zhao H. An efficient heterogeneous cross‐coupling
of aryl iodides with diphenylphosphine catalyzed
by copper (I) immobilized in MCM‐41. Appl
Organometal Chem. 2018;e4417. https://doi.org/
10.1002/aoc.4417
[20] a) C. D. Nunes, A. A. Valente, M. Pillinger, A. C. Fernandes, C. C.
Romao, J. Rocha, I. S. Goncalves, J. Mater. Chem. 2002, 12, 1735.
b) M. Jia, A. Seifert, W. R. Thiel, Chem. Mater. 2003, 15, 2174.
[21] a) A. Corma, E. Gutierrez‐Puebla, M. Iglesias, A. Monge, S.
Perez‐Ferreras, F. Sanchez, Adv. Synth. Catal. 2006, 348, 1899.
b) G. Villaverde, A. Corma, M. Iglesias, F. Sanchez, ACS Catal.
2012, 2, 399. c) W. Yang, R. Zhang, F. Yi, M. Cai, J. Org. Chem.
2017, 82, 5204.