Novel and facile procedure for the synthesis of Ni(II) and Pd(II) PSCOP pincer complexes. Evaluation of their catalytic activity on C-S, C-Se and C-C cross coupling reactions

Article abstract of DOI:10.1016/j.ica.2019.119283

A new and facile procedure for the synthesis of non-symmetric phosphinito-thiophosphinito PSCOP pincer complexes based on Ni(II) and Pd(II) was developed. The synthesis of the complexes was carried out in a single step, starting from 3,3-dihydroxydiphenyldisulfide. The Ni(II) complexes were tested as catalysts in C-S and C-Se coupling reactions, being the ^tBu derivative 3-Ni the one exhibiting the best performance in both transformations. In this case, the sterics of the substrates was studied, showing that higher steric hindrance leads to lower yields. Analogously, the Pd(II) complexes were used as catalyst in Suzuki-Miyaura couplings of para-substituted bromobenzenes and phenyl boronic acid, being the analogous ^tBu derivative complex 3-Pd the best catalysts for this process, exhibiting tolerance to a wide range of functional groups.

Full text of DOI:10.1016/j.ica.2019.119283

InorganicaChimicaActaxxx(xxxx)xxxx
Contents lists available at ScienceDirect
Inorganica Chimica Acta
journal homepage: www.elsevier.com/locate/ica
Research paper
Novel and facile procedure for the synthesis of Ni(II) and Pd(II) PSCOP
pincer complexes. Evaluation of their catalytic activity on C-S, C-Se and C-C
cross coupling reactions
Bianca X. Valderrama-García, Ernesto Rufino-Felipe, Hugo Valdés, Simón Hernandez-Ortega,
Bethsy Adriana Aguilar-Castillo, David Morales-Morales⁎
Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Ciudad de México, CP 04510, Mexico
A R T I C L E I N F O
A B S T R A C T
Keywords:
A new and facile procedure for the synthesis of non-symmetric phosphinito-thiophosphinito PSCOP pincer
complexes based on Ni(II) and Pd(II) was developed. The synthesis of the complexes was carried out in a single
step, starting from 3,3-dihydroxydiphenyldisulfide. The Ni(II) complexes were tested as catalysts in C-S and C-Se
PSCOP pincer compounds
Nickel complexes
Palladium complexes
Cross-coupling
C-S coupling
C-Se coupling
t
coupling reactions, being the Bu derivative 3-Ni the one exhibiting the best performance in both transforma-
tions. In this case, the sterics of the substrates was studied, showing that higher steric hindrance leads to lower
yields. Analogously, the Pd(II) complexes were used as catalyst in Suzuki-Miyaura couplings of para-substituted
bromobenzenes and phenyl boronic acid, being the analogous tBu derivative complex 3-Pd the best catalysts for
this process, exhibiting tolerance to a wide range of functional groups.
Suzuki-Miyaura reaction
1. Introduction
catalytic activity in C-S couplings, obtaining yields up to 99% in 16 h
[23b]. Recently, Beweries et al. reported a PSCOPNi-based compound
For the last 20 years, pincer complexes have been widely studied
and found applications in different areas of chemistry [1]. In particular,
they have probe to be very efficient catalysts, capable to promote a
wide range of chemical transformations such as allylic additions, hy-
drosilylation, CO2 reduction and cross coupling reactions, among others
[1–12]. These applications being attributed to their high thermal sta-
bility and reactivity, and to their relative simple synthesis and func-
tionalization, allowing the fine tuning of both their sterics and elec-
tronics.
(Scheme 1) and its catalytic evaluation in Kumada couplings [25]. The
catalyst performed well with yields up to 51% under mild conditions.
Moreover, recently non-symmetric pincer complexes have attracted
much attention [1f]. However, their syntheses are sometimes laborious
and often lead to low yields. Thus, on this opportunity we report a new,
facile and high yield procedure for the synthesis of non-symmetric
phophinito-thiophosphinito Ni(II) and Pd(II) PSCOP pincer compounds
based on the S-S cleavage of 3,3-dihydroxydiphenyldisulfide, and their
catalytic evaluation in C-S, C-Se and C-C coupling reactions.
However, their use as catalysts in the C-S (thiolation) and C–Se
(selenylation) coupling reactions has been poorly explored [13]. These
processes are important at the industrial level, since they allow the
production of a variety of synthetic intermediates with biological and
medicinal properties such as herbicides and drugs. C-S and C–Se cou-
plings have been promoted by different transition metal-based cata-
lysts, being the most common, Co [14], Pd [15], Cu [16], and Ni [17].
Regarding the ligands, different topologies and morphologies have been
explored, such as NNN [18], PNP [19], PCP [20], POCN [21], POCOP
[22], PSCOP [23], and SNS [24]. In this sense, our group described two
non-symmetric PSCOP pincer complexes based on Ni(II) and Pd(II)
(Scheme 1) [23], the complex PSCOPNiCl (Scheme 1) showed a good
2. Results and discussion
It is well known that the S-S bond in disulfides can be cleavage in
the presence of phosphines to produce the corresponding thiols [26].
Taking advantage of this reaction we envisioned the production of non-
symmetric pincer ligands by using the appropriate disulfide (Scheme 2).
Thus, we carried out the reaction of the commercially available 3,3-
dihydroxydiphenyldisulfide with a slightly excess of the corresponding
chlorophosphine in the presence of triethylamine as base to afford the
corresponding PSCOP pincer ligands. The ligands do not need to be
isolated and can be used without further purification in the metalation
⁎ Corresponding author.
E-mail address: damor@unam.mx (D. Morales-Morales).
https://doi.org/10.1016/j.ica.2019.119283
Received 21 July 2019; Received in revised form 13 November 2019; Accepted 13 November 2019
Availableonline15November2019
0020-1693/©2019ElsevierB.V.Allrightsreserved.
Pleasecitethisarticleas:BiancaX.Valderrama-García,etal.,InorganicaChimicaActa,https://doi.org/10.1016/j.ica.2019.119283

B.X. Valderrama-García, et al.
InorganicaChimicaActaxxx(xxxx)xxxx
C-S and C-Se couplings. Table 1 shows the results of the couplings of
iodobenzene with a series of disulfide and diselenide compounds. The
reactions were carried out in DMF at 110 °C for 4 h, in the presence of
Zn as necessary reducing agent and 0.16 mol % of catalyst loading.
Initially, the PSCOP-Ni(II) pincer complexes were evaluated using io-
dobenzene and phenyl disulphide, under these conditions complex 3-Ni
exhibited the best activity, affording 88% yield of the corresponding
sulfide (Entry 3, Table 1), while complexes 1-Ni and 2-Ni afforded
yields of only 26% and 63%, respectively (Entries 1 and 2, Table 1).
Being complex 3-Ni the best catalysts of the series, we were inter-
ested in studying the effect of the sterics of the substrates. For this
purpose, we chose five alkyl-disulfides with different steric demand,
namely methyl disulfide, isopropyl disulfide, sec-butyl disulfide, tert-
butyl disulfide and n-butyl disulfide. The best yields were observed with
those substrates with less steric hindrance, for instance, using the less
sterically hindered substrate, methyl disulfide, the yield was up to 60%,
while using a bulkier substrate such as tert-butyl disulfide the yield
dropped to only 2%. Additionally, the nickel complexes were used as
catalysts in C-Se couplings, using iodobenzene and phenyl diselenide
(Entries 9–11, Table 1). Once again, complex 3-Ni turned out to be the
best catalysts of the series for this process, achieving yields of 57% to
diphenylselenide, while yields using complexes 1-Ni and 2-Ni were of
48% and 55%, respectively, roughly following the same trend observed
in the C-S couplings.
O
O
O
S
S
S
PiPr2
Ph2P
Ph2P
iPr2P
Pd
Cl
PPh2
Ni
Cl
PPh2
Ni
Cl
Morales-Morales
Beweries
Scheme 1. POCSP non-symmetrical pincer complexes based on Ni(II) and Pd
(II).
Scheme 2. Synthesis of the Ni(II) and Pd(II) PSCOP phosphinito-thiopho-
sphinito pincer complexes.
step. Thus, addition of either, [PdCl2] or [NiCl2] to the reaction mixture
afforded the desired PSCOP-M(II) pincer compounds in good yields. All
the compounds were characterized by multinuclear NMR spectroscopy,
mass spectrometry and elemental analysis.
4. Catalytic evaluation of the PSCOP-Pd(II) pincer complexes
Compounds 1-Ni, 2-Ni and 1-Pd have been previously described,
and their spectroscopic data are in good agreement with those reported
in the literature [23,25]. Thus, the NMR spectra of compounds 3-Ni, 2-
Pd and 3-Pd exhibit the absence of the signal due to H1 (Scheme 2) at
7.4–7.9 ppm, suggesting metallation has occurred. As expected, the
spectra of all complexes showed three multiplets in the typical proton
aromatic region due to the pincer backbone. For example, 3-Ni shows
these signals at 6.82, 6.74 and 6.41 ppm for H3, H5 and H4, respectively.
The 13C{1H} NMR spectra provides further information about the
structures, with a signal due to the C-Ni appears at 117.79 ppm, while
signals corresponding to C-Pd are observed as doublets at about 115.60
(2JCP = 14 Hz) (3-Pd) and 117.23 (2JCP = 15 Hz) ppm (2-Pd) respec-
tively. Finally, their 31P{1H} NMR spectra showed two signals (doub-
lets) with an AB pattern. The resonances between 180.3 and 137.2 ppm
were attributed to the phosphinito fragment, while those due to the
thiophosphinito moiety were observed between 65.6 and 112.6 ppm.
The values of the coupling constants J(31P,31P) were typical for phos-
phorus trans to phosphorus, ranging from 291 to 472 Hz. The mass
spectra (FAB+) of the complexes confirmed the structures, exhibiting
the molecular ions at 506 m/z for 3-Ni, 498 m/z for 2-Pd and 554 m/z
for 3-Pd, respectively.
Furthermore, the molecular structures of 3-Ni and 2-Pd were un-
equivocally determined by single crystal X-ray diffraction studies.
Suitable crystals were obtained by slow evaporation of solutions of the
complexes in a CH2Cl2/iPrOH solvent mixture. Compound 3-Ni crys-
tallized in a monoclinic system with a Cc space group, while complex 2-
Pd crystallized in a triclinic system with a P-1 space group. The mole-
cular structures of 3-Ni and 2-Pd are shown in Fig. 1. In both cases, the
metal centers showed slightly distorted square-planar geometries, being
coordinated to the pincer ligand in the usual tridentate manner with
one chloride ligand completing their coordination spheres with bond
length and angles similar to those described in the literature for related
compounds [23,25]. Worth of a note that both molecular structures
exhibited positional disorder in the central aromatic ring and bridge
atoms (O and S).
Furthermore, the palladium complexes were evaluated as catalysts
in Suzuki-Miyaura couplings (Table 2). The reactions were carried out
in toluene at 100 °C for 90 min, using a catalyst loading of 0.1 mol %
and K2CO3 as base. Experiments were performed using bromobenzene
and phenylboronic acid as substrates in order to determine the best
catalysts of the series, resulting complex 3-Pd to be the best, affording
96% yield to the corresponding biphenyl, while complexes 1-Pd and 2-
Pd showed yields of only 64 and 72%, respectively. Noteworthy the fact
that this trend matches the results described above with complex 3-Ni
being the best of the series. This may be because the tert-butyl group
produces more electron rich metal centers than the isopropyl or the
phenyl groups [27], favoring the oxidative addition step of the catalytic
cycle; thus, favoring the enhanced catalytic activity observed.
In order to determine the tolerance to other functional groups under
these catalytic conditions, we carried out reactions using different para-
substituted bromobenzenes using complex 3-Pd as catalyst. In general,
the results indicate a great selectivity and tolerance to different func-
tional groups, such as aldehyde, ketone, nitrile, nitro, amine and alkyl.
The yields were good ranging from 60% to 99%. As expected, the
substrates with electron-donating groups exhibited lower yields than
those containing electron-withdrawing groups. It is worth to note that
no side products were observed in all catalytic reactions (i.e. homo-
coupling).
5. Conclusions
In summary, we have developed a novel and facile, high yield
strategy for the synthesis of non-symmetric Ni(II) and Pd(II) POCSP
pincer complexes starting from 3,3-dihydroxydiphenyldisulfide. The
molecular structures of 3-Ni and 2-Pd were unambiguously determined
by single crystal X-ray diffraction analyses. The POCSP-Ni(II) pincer
complexes were successfully used as catalysts for C-S and C–Se cross-
coupling reactions, being complex 3-Ni the most active in both trans-
formations. Noteworthy the fact that C-S couplings are affected by the
steric nature of the substrates being the less bulky disulfides the ones
exhibiting the best yields. Moreover, the POCSP-Pd(II) pincer com-
plexes were used as catalysts on Suzuki-Miyaura couplings, resulting
complex 3-Pd the best for this process yielding up to 99% of the pro-
duct, with good selectivities and tolerance to different functional
3. Catalytic evaluation of the PSCOP-Ni(II) pincer complexes
The catalytic activity of the PSCOP-Ni(II) complexes was studied in
2

B.X. Valderrama-García, et al.
InorganicaChimicaActaxxx(xxxx)xxxx
Fig. 1. Molecular structure of complex 3-Ni and 2-Pd. Hydrogen atoms and disordered counterparts were omitted for clarity. Ellipsoids are shown at 40% level of
probability. Selected bond lengths, 3-Ni (Å): Ni–C1 1.899(7), P1–O1a 1.593(11), P2–O1b 1.550(17), P2–S5 2.18(4), P1–S1b 2.093(8). Selected bond angles (°):
P1–Ni–P2 171.24(8), C–Ni–Cl 178.3(2). 2-Pd (Å): Pd–C1a 2.000(4), Pd–C1b 2.000(2), Pd–P1 2.263(15), Pd–P2 2.2725(15), Pd–Cl 2.3686(15), P1–O1a 1.6550(15),
P2–O1b 1.555(15), P2–S1a 2.133(4), P1–S1b 2.062(7). Selected bond angles (°): P1–Pd–P2 168.14, C1a–Pd–Cl 175.8(7), C1b–Pd–Cl 176.6(7).
groups.
Thus, we believe that this new procedure may allow the preparation
of more sophisticated pincer topologies with new potential applica-
tions, this being particularly true in the case of catalysis.
(d, PO, J(31P, 31P) = 292), 112.6 (d, PS, J(31P, 31P) = 292), MS-FAB+
,
m/z (%): 506 (1 0 0) [M+], 471 (55) [M+- Cl]. Anal. Calc. for
C22H39ClOSP2Ni (507.70 g∙ mol−1): C 52.05, H 7.74, S 6.31; Found: C
51.98, H 7.78, S 6.26.
6. Experimental part
6.3. Synthesis of 2-Pd
All reactions were carried out under nitrogen with standard Schlenk
techniques unless otherwise stated. All chemical compounds were
commercially obtained from Aldrich Chemical Co. and used as received
without further purification. Melting points were recorded on a Mel-
Temp II apparatus and are reported without correction. The 1H,
13C{1H}, 31P{1H} NMR spectra were recorded on a JEOL GX300 spec-
trometer. Elemental analyses were performed in a Thermo Scientific
Flash 2000 elemental analyzer, using a Mettler Toledo XP6 Automated-
S Microbalance and sulfanilamide as standard (Thermo Scientific BN
217826, attained values N = 16.40%, C = 41.91%, H = 4.65%, y
S = 18.63%; certified values N = 16.26%, C = 41.81%, H = 4.71%, y
S = 18.62%). Positive-ion FAB mass spectra were recorded on a JEOL
JEM-AX505HA mass spectrometer.
The synthesis of 2-Pd was carried out using chlorodiisopropylpho-
sphine (0.5 mL, 3.2 mmol) and [PdCl2] (283 mg, 1.6 mmol). Yield:
765 mg (96%). Melting point: 138–140 °C. 1H NMR (CDCl3, 300 MHz) δ
6.93 (dt, 2H, Ar–H, J(1H,1H) = 7.8 and 6.0 Hz), 6.60 (dd, 1H, Ar–H, J
(1H,1H) = 6.9 and 1.83 Hz), 2.32–2.20 (m, 4H, CH), 1.78–1.60 (m,
24H, CH3). 13C{1H} NMR (75 MHz, CDCl3): δ 166.0 (s, COP), 145.81 (s,
CPS), 127.03 (s, C-H Ar), 117.23 (d, C–Pd, J(13C, 31P) = 15.08 Hz)
108.74 (d, C-H Ar, J(13C, 31P) = 15.68 Hz), 28.93 (d, C-H, J(13C,
31P) = 5.20 Hz), 27.66 (d, C-H, J(13C, 31P) = 2.56 Hz), 27.61 (d, C-H, J
(
13C, 31P) = 2.41 Hz), 18.69 (d, CH3, J(13C, 31P) = 6.40 Hz), 17.82 (d,
CH3, J(13C, 31P) = 2.33 Hz), 17.41 (d, CH3, J(13C, 31P) = 6.55 Hz),
17.40 (s, CH3). 31P{1H} NMR (121 MHz, CDCl3): δ 184.50 (d, PO, J(31P,
31P) = 408), 100.60 (d, PS, J(31P, 31P) = 408), MS-FAB+, m/z (%): 498
(25) [M+], 463 (4) [M+- Cl]. Anal. Calc. for C18H31ClOSP2Pd (499.32 g∙
mol−1): C 43.30, H 6.26, S 6.42; Found: C 43.35, H 6.29, S 6.34.
6.1. General procedure for the synthesis of the PSCOP pincer complexes
A Schlenk flask was charged with 3,3-dihydroxydiphenyldisulfide
(200 mg, 0.8 mmol), toluene (10 mL), and triethylamine (0.5 mL,
3.5 mmol). The resulting solution was stirred for 10 min at room tem-
perature. Then, the corresponding chlorophosphine (3.2 mmol) was
added to the Schlenk and the reaction mixture was refluxed for 12 h.
After this time, the reaction mixture was cooled to room temperature
and filtered via cannula. [NiCl2] or [PdCl2] (1.6 mmol) was added to the
resulting solution, and then the reaction was refluxed for 16 h. After
this time, the solution was cooled to room temperature and all volatiles
removed under high vacuum. The crude product was purified by
chromatographic column, using a 2:1 solution of CH2Cl2/pentane.
6.4. Synthesis of 3-Pd
The synthesis of 3-Pd was carried out using di-tert-butyl-
chlorophosphine (0.6 mL, 3.2 mmol) and [PdCl2] (283 mg, 1.6 mmol).
Yield: 834 mg (94%). Melting point: 138–141 °C. 1H NMR (CDCl3,
300 MHz) δ 6.82 (t, 2H, Ar–H, J(1H,1H) = 6.60 Hz), 6.51 (d, 1H, Ar–H,
J(1H,1H) = 7.20 Hz), 1.57–1.12 (m, 36H, CH3). 13C{1H} NMR (75 MHz,
CDCl3): δ 153.0 (s, COP), 144.5 (s, CSP), 125.6 (s, C-H Ar), 115.6 (d,
C–Pd, J(13C, 31P) = 14.2 Hz), 107.4 (s, C-H Ar), 39.10 (d, C(CH3)3, J
(
13C, 31P) = 5.40 Hz), 38.95 (d, C(CH3)3, J(13C, 31P) = 5.25 Hz), 38.56
(d, C(CH3)3, J(13C, 31P) = 3.30 Hz), 38.52 (d, C(CH3)3, J(13C,
31P) = 3.20 Hz), 28.08 (d, CH3, J(13C, 31P) = 1.05 Hz), 26.81 (d, CH3, J
(
13C, 31P) = 5.40 Hz). 31P{1H} NMR (121 MHz, CDCl3): δ 188.43 (d,
6.2. Synthesis of 3-Ni
PO, J(31P, 31P) = 383), 111.25 (d, PS, J(31P, 31P) = 383), MS-FAB+, m/
z
C
(%): 554 (15) [M+], 519 (65) [M+
- Cl]. Anal. Calc. for
The synthesis of 3-Ni was carried out using di-tert-butylchloropho-
sphine (0.6 mL, 3.2 mmol) and [NiCl2] (200 mg, 1.6 mmol). Yield:
657 mg (81%). Melting point: 220–222 °C. 1H NMR (CDCl3, 300 MHz) δ
22H39ClOSP2Pd (555.43 g∙ mol−1): C 47.57, H 7.08, S 6.38; Found: C
47.52, H 7.12, S 6.28.
6.82 (t, 1H, Ar–H, J(1H,1H) = 7.5 Hz), 6.74 (d, 1H, Ar–H,
J
(1H,1H) = 7.5 Hz), 6.41 (d, 1H, Ar–H, J(1H,1H) = 7.2 Hz), 1.55 (m,
36H, CH3). 13C{1H} NMR (75 MHz, CDCl3): δ 164.0 (s, COP), 147.81 (s,
CPS), 135.13(s, C-H Ar), 130.39 (s, C-H Ar), 117.79 (s, C–Ni), 112.90 (s,
C-H Ar), 38.92 (m, C(CH3)3, 38.51 (m, C(CH3)3, 38.49 (m, C(CH3)3,
28.28 (s, CH3), 26.52 (s, CH3).31P{1H} NMR (121 MHz, CDCl3): δ 180.8
6.5. General procedure for the C-S cross-coupling
A Schlenk tube was charged with a solution of 2 mmol of iodo-
benzene, 1 mmol of the corresponding alkyl- or aryldisulfide, 1.2 mmol
of zinc dust, 0.16 mol % of the catalyst in 2.0 mL of DMF. The tube was
3

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InorganicaChimicaActaxxx(xxxx)xxxx
Table 1
C-S and C–Se couplings catalyzed by the PSCOP-Ni(II) complexesa.
I
0.16 mol % [Ni]
E
R1
R
1
E
1/2
+
E
R1
Zn, DMF
Substrate
E = S, Se
Catalyst
Entry
Product
Yield %b
26
1
1-Ni
2-Ni
3-Ni
S
S
S
S
S
S
S
S
S
2
3
63
88
4
5
3-Ni
3-Ni
60
22
S
S
S
S
S
S
S
S
6
3-Ni
14
S
S
S
7
8
9
3-Ni
3-Ni
1-Ni
2
S
1
S
S
S
48
Se
Se
Se
Se
Se
Se
Se
10
11
2-Ni
3-Ni
55
57
Se
Se
a
Reaction conditions: 2 mmol of iodobenzene, 1 mmol of aryl(or alkyl)disulphide or phenyl diselenide, 1.2 mmol of Zn, 2 mL of DMF, 0.16 mol % of catalyst,
110 °C for 4 h.
b
Yields were determined by GC–MS and are based on residual iodobenzene and are the average of two runs.
sealed and heated at 110 °C for 4 h. After this time, the reaction mixture
was cooled to room temperature, and the solution was analyzed by gas
chromatography (GC–MS) (Quantitative analyses were performed on an
Agilent 6890 N GC with a 30.0 m DB-1MS capillary column coupled to
an Agilent 5973 Inert Mass Selective detector).
4

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Table 2
Suzuki-Miyaura cross-couplings catalyzed by the PSCOP-Pd(II) complexesa.
Br
(HO)2B
0.1 mol % [Pd]
K2CO3, toluene
R1
+
R1
Entry
1
Catalyst
Substrate
Product
Yield %b
64
1-Pd
2-Pd
3-Pd
3-Pd
Br
Br
Br
2
3
4
72
96
98
Br
OHC
OHC
H3COC
NC
5
3-Pd
98
Br
H3COC
6
7
3-Pd
3-Pd
99
99
Br
NC
Br
O2N
NH2
O2N
8
3-Pd
3-Pd
60
84
Br
H2N
9
a
Br
Reaction conditions: 4 mmol of the aryl bromides, 4.8 mmol of phenylboronic acid, 4.8 mmol K2CO3, 12 mL of toluene, 0.1 mol % of catalyst, 110 °C for 90 min.
Yields were determined by GC–MS and are based on residual aryl bromide and are the average of two runs.
b
6.6. General procedure for the C-Se cross-coupling
6.7.1. Data collection and refinement for compounds 3-Ni and 2-Pd
Prism crystals of 3-Ni and 2-Pd were grown from CH2Cl2/iPrOH and
mounted on glass fibers, then placed on a Bruker Smart Apex II dif-
fractometer with a Mo-target X-ray source (λ = 0.71073 Å). The de-
tector was placed at a distance of 5.0 cm from the crystals and frames
were collected with a scan width of 0.5 in ω and an exposure time of
10 s/frame. Frames were integrated with the Bruker SAINT software
package using a narrow-frame integration algorithm. Non-systematic
absences and intensity statistics were used in monoclinic Cc and tri-
clinic P1 space groups respectively. The structures were solved using
Patterson methods using SHELXS-2014/7 program [28]. The remaining
atoms were located via a few cycles of least squares refinements and
difference Fourier maps. Hydrogen atoms were input at calculated
positions and allowed to ride on the atoms to which they are attached.
Thermal parameters were refined for hydrogen atoms on the phenyl
groups using a Ueq = 1.2 Å to precedent atom. The final cycles of re-
finement were carried out on all non-zero data using SHELXL-2014/7
[28]. Absorption corrections were applied using SADABS program. The
fragments S-Ph-O, are disordered and were modelled and refined ani-
sotropically in two positions using a variable site occupational factor
A Schlenk tube was charged with a solution of 2 mmol of iodo-
benzene, 1 mmol of phenyl diselenide, 1.2 mmol of zinc dust, 0.16 mol
% of the catalyst in 2.0 mL of DMF. The tube was sealed and heated at
110 °C for 4 h. After this time, the reaction mixture was cooled to room
temperature, and the solution was analyzed by gas chromatography
(GC–MS) (Quantitative analyses were performed on an Agilent 6890 N
GC with a 30.0 m DB-1MS capillary column coupled to an Agilent 5973
Inert Mass Selective detector).
6.7. General procedure for the Suzuki-Miyaura cross-coupling
A Schlenk tube was charged with phenylboronic acid (4.8 mmol),
K2CO3 (4.8 mmol), the catalyst (0.1% mol), the corresponding aryl
halide (4 mmol) and toluene (12 mL). The tube was sealed and heated
at 110 °C for 1.5 h. The yields of the reactions were calculated by gas
chromatography (GC–MS) (Quantitative analyses were performed on an
Agilent 6890 N GC with a 30.0 m DB-1MS capillary column coupled to
an Agilent 5973 Inert Mass Selective detector).
5

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InorganicaChimicaActaxxx(xxxx)xxxx
(SOF).
b) P. Gogoi, S. Hazarika, M.J. Sarma, K. Sarma, P. Barman, Tetrahedron 70 (2014)
7484–7489;
c) J. Zhang, C.M. Medley, J.A. Krause, H. Guan, Organometallics 29 (2010)
6393–6401.
Acknowledgments
[14] Y.-C. Wong, T.T. Jayanth, C.H. Cheng, Org. Lett. 8 (2006) 5613–5616.
[15] a) M. Platon, N. Wijaya, V. Rampazzi, L. Cui, Y. Rousselin, M. Saeys, J.-C. Hierso,
Chem. Eur. J. 20 (2014) 12584–12594;
b) A. Byeun, K. Baek, M.S. Han, S. Lee, Tetrahedron Lett. 54 (2013) 6712–6715;
c) C.F. Fu, Y.-H. Liu, S.M. Peng, S.T. Liu, Tetrahedron 66 (2010) 2119–2122.
[16] a) H. Wang, L. Jiang, T. Chen, Y. Li, Eur. J. Org. Chem. (2010) 2324–2329;
b) S. Jammi, S. Sakthivel, L. Rout, T. Mukherjee, S. Mandal, R. Mitra, P. Saha,
T. Punniyamurthy, J. Org. Chem. 74 (2009) 1971–1976;
c) S. Zhang, P. Qian, M. Zhang, M. Hu, J. Cheng, J. Org. Chem. 75 (2010)
6732–6735.
We would like to thank Chem. Eng. Luis Velasco Ibarra, Dr.
Francisco Javier Pérez Flores, Q. Eréndira García Ríos, M.Sc. Lucia del
Carmen Márquez Alonso, M.Sc. Lucero Ríos Ruiz, Q. María de la Paz
Orta Pérez and Q. Roció Patiño-Maya for technical assistance. H. V.
would like to thank Programa de Becas Posdoctorales-DGAPA-UNAM
for postdoctoral scholarships (Oficio: CJIC/CTIC/4751/2018). E.R.F
would like to thank the CONACYT postdoctoral fellowship (2018-
000005-01NACV-00391). The financial support of this research by
PAPIIT-DGAPA-UNAM (PAPIIT IN207317) and CONACYT A1-S-33933
is gratefully acknowledged.
[17] a) P. Guan, C. Cao, Y. Liu, Y. Li, P. He, Q. Chen, G. Liu, Y. Shi, Tetrahedron Lett. 53
(2012) 5987–5992;
b) S. Jammi, P. Barua, L. Rout, P. Saha, T. Punniyamurthy, Tetrahedron Lett. 49
(2008) 1484–1487;
b) R. Singh, B.K. Allam, N. Singh, K. Kumari, S.K. Singh, K.N. Singh, Adv. Synt.
Catal. 357 (2015) 1181–1186;
Supplementary Information
c) Y. Zhang, K.C. Ngeow, J.Y. Ying, Org. Lett. 9 (2007) 3495–3498.
[18] a) U.N. Patel, S. Jain, D.K. Pandey, R.G. Gonnade, K. Vanka, B. Punji,
Organometallics 37 (2018) 1017–1025;
Supplementary data for compounds 3-Ni and 2-Pd were deposited
at the Cambridge Crystallographic Data Centre. Copies of this in-
formation are available free of charge on request from The Director,
CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK (Fax: +44-1223-
336033; e-mail: deposit@ccdc.cam.ac.uk or www: http://www.ccdc.
cam.ac.uk) quoting the deposition numbers CCDC 1913480-1913481.
b) U.N. Patel, D.K. Pandey, R.G. Gonnade, B. Punji, Organometallics 35 (2016)
1785–1793;
c) A.R. Corcos, O. Villanueva, R.C. Walroth, S.K. Sharma, J. Bacsa, K.M. Lancaster,
C.E. MacBeth, J.F. Berry, J. Am. Chem. Soc. 138 (2016) 1796–1799;
d) O. Baldovino-Pantaleón, S. Hernandez-Ortega, D. Morales-Morales, Adv. Synth.
Catal. 348 (2006) 236–242;
e) O. Baldovino-Pantaleón, S. Hernandez-Ortega, D. Morales-Morales, Inorg.
Chem. Commun. 8 (2005) 955–959.
[19] a) M. Tamizmani, R. Kankanala, C. Sivasankar, J. Organomet. Chem. 763–764
(2014) 6–13;
References
b) J.I. van der Vlugt, M.A. Siegler, M. Janssen, D. Vogt, A.L. Spek, Organometallics
28 (2009) 7025–7032;
c) L.-C. Liang, P.-S. Chien, Y.-L. Huang, J. Am. Chem. Soc. 128 (2006)
[1] a) D. Morales-Morales, Revista de la Sociedad Química de México 48 (2004)
338–346;
15562–15563.
b) D. Morales-Morales, C.M. Jensen (Eds.), The Chemistry of Pincer Compounds,
Elsevier, 2007;
c) D. Morales-Morales, Mini-Rev. Org. Chem. 5 (2008) 141–152;
d) J. Serrano-Becerra, D. Morales-Morales, Curr. Org. Synth. 6 (2009) 169–192;
e) D.F. Brayton, P.R. Beaumont, E.Y. Fukushima, H.T. Sartain, D. Morales-Morales,
C.M. Jensen, Organometallics 33 (2014) 5198–5202;
f) M. Asay, D. Morales-Morales, Dalton Trans. 44 (2015) 17432–17447;
g) M. Asay, D. Morales-Morales, Top. Organomet. Chem. 54 (2016) 239–268;
h) H. Valdés, L. González-Sebastián, D. Morales-Morales, J. Organomet. Chem. 845
(2017) 229–257;
i) D. Morales-Morales (Ed.), Pincer Compounds Chemistry and Applications,
Elsevier, 2018;
j) D. Morales-Morales, H. Valdes, M.A. García-Eleno, D. Canseco-Gonzalez,
ChemCatChem 10 (2018) 3136–3172;
k) H. Valdés, E. Rufino-Felipe, D. Morales-Morales, J. Organomet. Chem. 898
[20] a) W.S. Tay, X.-Y. Yang, Y. Li, S.A. Pullarkat, P.-H. Leung, Chem. Commun. 53
(2017) 6307–6310;
b) X.-Y. Yang, Y.-X. Jia, W.S. Tay, Y. Li, S.A. Pullarkat, P.-H. Leung, Dalton Trans.
45 (2016) 13449–13455;
c) A. Castonguay, C. Sui-Seng, D. Zargarian, A.L. Beauchamp, Organometallics 25
(2006) 602–608.
[21] a) C. Wang, Y. Li, B. Lu, X.-Q. Hao, J.-F. Gong, M.-P. Song, Polyhedron 143 (2018)
184–192;
b) S.M. Khake, R.A. Jagtap, Y.B. Dangat, R.G. Gonnade, K. Vanka, B. Punji,
Organometallics 35 (2016) 875–886;
c) D.K. Pandey, S.M. Khake, R.G. Gonnadeb, B. Punji, RSC Adv. 5 (2015)
81502–81514.
[22] a) E.G. Morales-Espinoza, R. Coronel-García, H. Valdés, R. Reyes-Martínez,
J.M. German-Acacio, B.A. Aguilar-Castillo, R.A. Toscano, N. Ortiz-Pastrana,
D. Morales-Morales, J. Organomet. Chem. 867 (2018) 155–160;
b) Q.-Q. Ma, T. Liu, S. Li, J. Zhang, X. Chen, H. Guan, Chem. Commun. 52 (2016)
14262–14265;
(2019) 120864;
l) L. Gonzalez-Sebastián, D. Morales-Morales, J. Organomet. Chem. 893 (2019)
39–51.
c) D. Adhikari, M. Pink, D.J. Mindiola, Organometallics 28 (2009) 2072–2077;
d) D. Adhikari, S. Mossin, F. Basuli, J.C. Huffman, R.K. Szilagyi, K. Meyer,
D.J. Mindiola, J. Am. Chem. Soc. 130 (2008) 3676–3682;
e) V. Gomez-Benitez, O. Baldovino-Pantaleón, C. Herrera-Álvarez, R.A. Toscano,
D. Morales-Morales, Tetrahedron Lett. 47 (2006) 5059–5062.
[23] a) J.M. Serrano-Becerra, S. Hernández-Ortega, D. Morales-Morales, Inorg. Chim.
Acta 363 (2010) 1306–1310;
b) J.M. Serrano-Becerra, H. Valdés, D. Canseco-González, V. Gómez-Benítez,
S. Hernández-Ortega, D. Morales-Morales, Tetrahedron Lett. 59 (2018) 3377–3380.
[24] M. Basauri-Molina, S. Hernández-Ortega, D. Morales-Morales, Eur. J. Inorg. Chem.
(2014) 4619–4625.
[25] P. Hasche, M. Joksch, G. Vlachopoulou, H. Agarwala, A. Spannenberg, T. Beweries,
Eur. J. Inorg. Chem. (2018) 676–680.
[26] J.A. Burns, J.C. Butler, J. Moran, G.M. Whitesides, J. Org. Chem. 56 (1991)
2648–2650.
[27] C.A. Tolman, J. Am. Chem. Soc. 92 (1970) 2953–2956.
[28] G.M. Sheldrick, Acta Cryst. C71 (2015) 3–8.
[2] W. Kuriyama, T. Matsumoto, O. Ogata, Y. Ino, K. Aoki, S. Tanaka, K. Ishida,
T. Kobayashi, N. Sayo, T. Saito, Org. Process Res. Dev. 16 (2012) 166–171.
[3] N. Selander, K.J. Szabó, Chem. Rev. 111 (2011) 2048–2076.
[4] S. Chakraborty, P. Bhattacharya, H. Dai, H. Guan, Acc. Chem. Res. 48 (2015)
1995–2003.
[5] G. van Koten, R.A. Gossage (Eds.), The Privileged Pincer-Metal Platform:
Coordination Chemistry & Applications, Springer International Publishing, Cham,
2016.
[6] D. Srimani, A. Mukherjee, A.F.G. Goldberg, G. Leitus, Y. Diskin Posner,
L.J.W. Shimon, Y. Ben David, D. Milstein, Angew. Chem. 127 (2015) 12534–12537.
[7] J.R. Khusnutdinova, J.A. Garg, D. Milstein, ACS Catal. 5 (2015) 2416–2422.
[8] C. Gunanathan, D. Milstein, Chem. Rev. 114 (2014) 12024–12087.
[9] T. Zell, Y. Ben David, D. Milstein, Angew. Chem. Int. Ed. Engl. 53 (2014)
4685–4689.
[10] E. Balaraman, E. Khaskin, G. Leitus, D. Milstein, Nat. Chem. 5 (2013) 122–125.
[11] M. Albrecht, G. van Koten, Angew. Chem. Int. Ed. Engl. 40 (2001) 3750–3781.
[12] M.E. van der Boom, D. Milstein, Chem. Rev. 103 (2003) 1759–1792.
[13] a) G.T. Venkanna, H.D. Arman, Z.J. Tonzetich, ACS Catal. 4 (2014) 2941–2950;
6