Rhodium-Catalyzed Carbonylative Synthesis of Aryl Salicylates from Unactivated Phenols

Article abstract of DOI:10.1021/acs.orglett.0c02133

A rhodium-catalyzed carbonylative transformation of unactivated phenols to aryl salicylates is described. This protocol is characterized by utilizing 1,3-rhodium migration as the key step to provide direct access to synthesize ohydroxyaryl esters. Various desired aryl o-hydroxybenzoates were produced in moderate to excellent yields with bis(dicyclohexylphosphino)ethane (DCPE) as the ligand. Interestingly, diphenyl carbonate was formed as the main product when 1,3-bis(diphenylphosphino)propane (DPPP) was used as the ligand. A plausible reaction mechanism is proposed.

Full text of DOI:10.1021/acs.orglett.0c02133

pubs.acs.org/OrgLett
Letter
Rhodium-Catalyzed Carbonylative Synthesis of Aryl Salicylates from
Unactivated Phenols
Han-Jun Ai, Youcan Zhang, Fengqian Zhao, and Xiao-Feng Wu*
Cite This: https://dx.doi.org/10.1021/acs.orglett.0c02133
Read Online
sı
*
Metrics & More
Article Recommendations
Supporting Information
ACCESS
ABSTRACT: A rhodium-catalyzed carbonylative transformation of unactivated
phenols to aryl salicylates is described. This protocol is characterized by utilizing 1,3-
rhodium migration as the key step to provide direct access to synthesize o-
hydroxyaryl esters. Various desired aryl o-hydroxybenzoates were produced in
moderate to excellent yields with bis(dicyclohexylphosphino)ethane (DCPE) as the
ligand. Interestingly, diphenyl carbonate was formed as the main product when 1,3-
bis(diphenylphosphino)propane (DPPP) was used as the ligand. A plausible reaction
mechanism is proposed.
ransition-metal-catalyzed carbonylation reaction has
establish a rhodium-catalyzed system that allows the effective
Temerged as one of the most powerful methods for the carbonylative transformation of various unactivated phenols to
the corresponding aryl salicylates (Scheme 1, path d). Such a
synthesis of carbonyl-containing compounds after over a half-
century of developments.1 Employing CO as a cheap and
readily available C1 source, given the directness and high
atomic economy of this strategy, many carbonylative
procedures have even been industrialized.1,2 Among the
established procedures, the synthesis of diphenyl carbonate
(DPC) is regarded as a very successful and important case.3
DPC is a key material of polycarbonate resin production.
The annual demand of polycarbonates reached 5 million tons
in 2015,3 which makes DPC a high-value building block in the
chemical industry. Traditional commercial routes for DPC
synthesis include the reaction of phosgene with phenol4 and
transesterification of phenol with dimethyl carbonate.5
Compared with these solutions, the direct oxidative carbon-
ylation of phenol demonstrates great advantages and avoids the
use of extremely toxic phosgene as the most potent
improvement, thereby gradually replacing the traditional
processes.3,6 However, in the oxidative carbonylation of phenol
for DPC production, phenyl salicylate (PS) is known as an
inevitable side product.3,6,7 Nevertheless, phenyl salicylate is
also a valuable compound. It is utilized to prepare fine
chemicals including drugs, food preservatives, UV absorbers,
pharmaceuticals, perfumes, and cosmetics.8 However, by
careful literature research, we are surprised that the direct
catalytic carbonylation protocol of phenol for the preparation
of PS has not been achieved to date.
Scheme 1. Methodologies for Aryl Salicylate Synthesis
protocol would constitute an alternative to the classical
esterification (Scheme 1, path a),11 the Smiles rearrangement
of an aryl ether (Scheme 1, path b),12 and the Fries
rearrangement from DPC conducted at high temperatures
and in the presence of Lewis acid (Scheme 1, path c).13
We began our studies by testing the oxidants using RhCl3 as
the catalyst and 1,3-bis(diphenylphosphino)propane (DPPP)
as the ligand (Table 1). Unexpectedly, only when 2,2,6,6-
tetramethyl-1-piperidine N-oxyl (TEMPO) was employed as
the oxidant could we detect the target product PS (2) in a
minor but meaningful amount together with DPC (3) as its
isomeric product with a significant yield. Other types of
oxidants such as nitrogen oxides, benzoquinone, and peroxides
Keeping in mind that the discovery of new carbonylative
protocols in this field will lead to efficient synthetic routes
toward advanced intermediates and the known achievements
of the rhodium catalyst in organic chemistry,9,10 we envisioned
that certain rhodium catalysts may be utilized to achieve the
carbonylation of phenol that selectivity leads to phenyl
salicylate. After systematic studies, we have been able to
Received: June 28, 2020
https://dx.doi.org/10.1021/acs.orglett.0c02133
© XXXX American Chemical Society
Org. Lett. XXXX, XXX, XXX−XXX
A

Organic Letters
pubs.acs.org/OrgLett
Letter
a
Table 1. Testing of Oxidants
Table 2. Optimization of Rh-Catalyzed Carbonylative
a
Transformation of Phenol
b
entry
solvent
ligand
DPPP
DPPP
DPPP
DPPP
DPPP
DPPP
DPPP
Xantphos
DPPB
CO (bar) conv. [%] yield (2:3) [%]
1
2
3
4
5
6
7
8
THF
PhMe
1
1
1
65
50
18
46 (35:65)
37 (87:13)
<10
DMSO
dioxane
mixture
mixture
mixture
mixture
mixture
mixture
mixture
mixture
mixture
mixture
mixture
1
1
6
56
62
69
82
79
34
79
64
50 (16:84)
53 (39:63)
44 (23:77)
61 (10:90)
35 (6:94)
11 (36:67)
51 (96:4)
<10
20
20
20
20
20
20
20
6
9
10
11
12
13
14
DPPE
a
Reaction conditions: phenol (0.5 mmol), oxidant (0.8 mmol), RhCl3
(0.025 mmol), DPPP (0.075 mmol), and 3 Å MS (10 mg) in 1,4-
dioxane (1 mL) at 120 °C for 24 h under 1 bar of CO and 5 bar of
N2. The yield was determined by GC with hexadecane as the internal
standard.
DPPM
DCPP·2BF4
DCPE
DCPE
DCPE
21
0
100
100
100
83 (>99:1)
80 (>99:1)
82 (>99:1)
c
15
6
gave extremely low conversions of phenol and failed to provide
the product 2 or 3. Then, modifying the catalytic system to
control the product ratio of 2 to 3 was the focus of our interest.
Especially, we turned our attention to increase the
conversion of phenol (1) and the selectivity of 2 (Table 2).
Compared with THF, PhMe, and DMSO, 1,4-dioxane was
superior as the solvent, and moderate conversion and yield
could be obtained with decreasing byproduct (Table 2, entries
1−4). It was found that use of a mixed solvent system of PhMe
and 1,4-dioxane exhibited a cooperative effect on the reactivity,
and the conversion and yield were further increased to 62%
and 53%, respectively (Table 2, entry 5). Then we increased
the pressure of CO to 20 bar, resulting in higher conversion
but lower selectivity (Table 2, entries 5−7). As anticipated,14
ligands played a crucial role by controlling the product ratio
(Table 2, entries 8−13). By adjusting the bite angle of the
bisphosphine ligand,15 changing the ligand to 1,2-bis-
(diphenylphosphino)ethane (DPPE), a similar conversion
(79%) but excellent selectivity of 2 (96:4) was obtained
(Table 2, entry 10). Moreover, employing DCPE, the bite
angle was an almost equal but more electron-rich ligand,
providing 2 in 83% yield and further inhibiting the generation
of 3 (Table 2, entry 13). Interestingly, as shown in entry 12,
DCPP·2BF4 hardly promoted the carbonylative conversion of
phenol. With regard to reaction conditions suitable for
practical applications, we conducted experiments under lower
pressure of CO and in which a reduced amount of rhodium
was used (Table 2, entries 14 and 15). To our delight, after
optimization, 82% yield of the desired 2 was obtained in the
presence of lower loading of rhodium catalyst under 6 bar of
CO.
a
Reaction conditions: phenol (0.5 mmol), TEMPO (0.8 mmol),
RhCl3 (0.025 mmol), ligand (0.075 mmol), and 3 Å MS (10 mg) in
b
solvent (1 mL) at 120 °C for 24 h. Determined by GC with
hexadecane as the internal standard. RhCl3 (0.0125 mmol) and
DPPP (0.0375 mmol). Mixture: 1,4-dioxane and PhMe (v/v =
0.4:0.6).
c
a
Table 3. Rh-Catalyzed Carbonylation of Phenols
With the objective of extending the scope of the reaction, we
investigated the reaction with various phenols. As shown in
Table 3, a wide range of phenols could be successful converted
into the corresponding o-hydroxyaryl ester 2−18. Notably, the
synthesis also proceeded successfully and provided 81%
isolated yield of 2 when we scaled up the reaction 10-fold,
thus providing potential opportunity for applications in large-
scale production. Generally, carbonylations of phenols bearing
electron-donating substituents proceeded well, for example, in
a
Reaction conditions: phenol (0.5 mmol), TEMPO (0.8 mmol),
RhCl3 (0.0125 mmol), DPPP (0.0375 mmol), and 3 Å MS (10 mg) in
1,4-dioxane (0.4 mL) and toluene (0.6 mL) at 120 °C for 24 h under
6 bar of CO. Isolated yield. 130 °C.
b
B
https://dx.doi.org/10.1021/acs.orglett.0c02133
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
substrates with groups such as 4-methoxy (4) and 4-alkyl (5, 6,
8, and 9). Meanwhile, electron-withdrawing substituents,
including 4-fluoro (11) and 4-chloro (12) groups, were
tolerated. It is also important to mention that substrates with a
strong electron-withdrawing group such as a cyano or nitro
group failed to give the desired products under our conditions.
Additionally, meta-substituted phenols provided two products
with the 4-substituted product as the main product (13, 14),
probably due to the influence of steric hindrance. Furthermore,
as shown for 15−18, the reaction was not hampered by the
presence of ortho-substituents.
Scheme 3. Proposed Mechanism
To gain some more mechanistic insight into the reaction
pathway, several control experiments were conducted (Scheme
2). Under the optimized conditions, 3 could not be converted
Scheme 2. Mechanistic Studies
and phenol to provide D. Finally, the aryl rhodium complex D
undergoes reductive elimination to produce the final ester
product 2 and, meanwhile, releases the Rh complex which will
be regenerated to give the active rhodium complex A under the
assistance of TEMPO17 and ready for the next catalytic cycle.
In conclusion, we have developed a rhodium-catalyzed
selective carbonylation of phenols. This catalytic system allows
the direct carbonylative conversion of various phenols to o-
hydroxyaryl esters. The control experiments and the
deuterated experiments suggest the reactions have undergone
a 1,3-rhodium migration process, which can be controlled by
the ligand.
ASSOCIATED CONTENT
* Supporting Information
■
sı
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.orglett.0c02133.
General comments, general procedure, mechanistic
studies, analytic data, and NMR spectra of products
(PDF)
into the ester 2 (Scheme 2A); meanwhile, 2 could not be
converted into 3 with DPPP as the ligand (Scheme 2B),
indicating that under this catalytic system products 2 and 3
were not rearranged into each other. In order to get more
evidence, deuterated experiments were conducted. 2-d1 was
not detected when 1-d1 was used as the substrate; rather, 65%
yield of 2 could be obtained (Scheme 2C). Thus, we
preliminarily proved our assumption about the 1,3-Rh
migration. Subsequently, kinetic isotope effect (KIE) experi-
ments were conducted by employing 1, 1-d1, and 1-d6. As
shown in Scheme 2D and 2E, the KIEs (kH/kD) were equal to
2.6 and 2.2, suggesting the ligand exchange step and the 1,3-Rh
migration process might be the rate-determining steps.
However, the fact that H/D on phenols (ArOH) exchanges
easily must be considered as well.
AUTHOR INFORMATION
Corresponding Author
■
Xiao-Feng Wu − Leibniz-Institut fur Katalyse e. V. an der
̈
̈
Universitat Rostock, 18059 Rostock, Germany; Dalian National
Laboratory for Clean Energy, Dalian Institute of Chemical
Physics, Chinese Academy of Sciences, 116023 Dalian, Liaoning,
China; orcid.org/0000-0001-6622-3328; Email: xiao-
feng.wu@catalysis.de
Authors
Han-Jun Ai − Leibniz-Institut fu
̈
r Katalyse e. V. an der
Universitat Rostock, 18059 Rostock, Germany
Youcan Zhang − Leibniz-Institut fur Katalyse e. V. an der
Universitat Rostock, 18059 Rostock, Germany
r Katalyse e. V. an der
̈
̈
̈
Based on the above results and previous reports,14,16
a
Fengqian Zhao − Leibniz-Institut fu
̈
plausible mechanism is proposed (Scheme 3). The reaction
starts with ligand exchange of phenol to rhodium complex A.
The resulting key intermediate B undergoes a 1,3-rhodium
migration process to provide C when DCPE is used as the
ligand. Interestingly, B is prone to the CO insertion step and at
the end gives product 3 when employing DPPP as the ligand.
On the other side, the aryl rhodium complex C reacts with CO
̈
Universitat Rostock, 18059 Rostock, Germany
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.orglett.0c02133
Notes
The authors declare no competing financial interest.
C
https://dx.doi.org/10.1021/acs.orglett.0c02133
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
(8) (a) Moerk Nielsen, N.; Bundgaard, H. Evaluation of
Glycolamide Esters and Various Other Esters of Aspirin as True. J.
Med. Chem. 1989, 32, 727−734. (b) Vanallan, J. A. The Salol
Reaction. J. Am. Chem. Soc. 1947, 69, 2913−2914. (c) Cascioferro, S.;
Raimondi, M. V.; Cusimano, M. G.; Raffa, D.; Maggio, B.; Daidone,
G.; Schillaci, D. Pharmaceutical Potential of Synthetic and Natural
Pyrrolomycins. Molecules 2015, 20, 21658−21671. (d) Hughes, C. C.;
Prieto-Davo, A.; Jensen, P. R.; Fenical, W. The Marinopyrroles,
Antibiotics of an Unprecedented Structure Class from a Marine
Streptomyces sp. Org. Lett. 2008, 10, 629−631.
ACKNOWLEDGMENTS
■
The authors thank the Chinese Scholarship Council (CSC) for
financial support. We also thank the analytical team of LIKAT
for their excellent analytic support.
REFERENCES
■
(1) (a) Kiss, G. Palladium-Catalyzed Reppe Carbonylation. Chem.
Rev. 2001, 101, 3435−3456. (b) Barnard, C. F. J. Palladium-Catalyzed
Carbonylation-A Reaction Come of Age. Organometallics 2008, 27,
5402−5422. (c) Cheng, L.-J.; Mankad, N. P. Cu-Catalyzed Hydro-
carbonylative C-C Coupling of Terminal Alkynes with Alkyl Iodides.
J. Am. Chem. Soc. 2017, 139, 10200−10203. (d) Matsubara, H.;
Kawamoto, T.; Fukuyama, T.; Ryu, I. Applications of Radical
Carbonylation and Amine Addition Chemistry: 1,4-Hydrogen Trans-
fer of 1-Hydroxylallyl Radicals. Acc. Chem. Res. 2018, 51, 2023−2035.
(e) Peng, J.-B.; Wu, F.-P.; Wu, X.-F. First-Row Transition-Metal-
Catalyzed Carbonylative Transformations of Carbon Electrophiles.
Chem. Rev. 2019, 119, 2090−2127.
(9) For selected review, see: Song, G.; Wang, F.; Li, X. C-C C-O and
C-N Bond Formation via Rhodium(III)-Catalyzed Oxidative C-H
Activation. Chem. Soc. Rev. 2012, 41, 3651−3678.
(10) For selected examples, see: (a) Ueura, K.; Satoh, T.; Miura, M.
An Efficient Waste-Free Oxidative Coupling via Regioselective C−H
Bond Cleavage: Rh/Cu-Catalyzed Reaction of Benzoic Acids with
Alkynes and Acrylates under Air. Org. Lett. 2007, 9, 1407−1409.
(b) Umeda, N.; Tsurugi, H.; Satoh, T.; Miura, M. Fluorescent
Naphthyl- and Anthrylazoles from the Catalytic Coupling of
Phenylazoles with Internal Alkynes through the Cleavage of Multiple
C-H Bonds. Angew. Chem., Int. Ed. 2008, 47, 4019−4022. (c) Stuart,
D. R.; Bertrand-Laperle, M.; Burgess, K. M. N.; Fagnou, K. Indole
Synthesis via Rhodium Catalyzed Oxidative Coupling of Acetanilides
and Internal Alkynes. J. Am. Chem. Soc. 2008, 130, 16474−16475.
(d) Guimond, N.; Fagnou, K. Isoquinoline Synthesis via Rhodium-
Catalyzed Oxidative Cross-Coupling/Cyclization of Aryl Aldimines
and Alkynes. J. Am. Chem. Soc. 2009, 131, 12050−12051. (e) Qi, X.;
Zhou, R.; Ai, H.-J.; Wu, X.-F. HMF and Furfural: Promising Platform
Molecules in Rhodium-Catalyzed Carbonylation Reactions for the
Synthesis of Furfuryl Esters and Tertiary Amides. J. Catal. 2020, 381,
215−221. (f) Ai, H.-J.; Wang, H.; Li, C.-L.; Wu, X.-F. Rhodium-
Catalyzed Carbonylative Coupling of Alkyl Halides with Phenols
under Low CO Pressure. ACS Catal. 2020, 10, 5147−5152.
(11) (a) Kuriakose, G.; Nagaraju, N. Selective synthesis of phenyl
salicylate (salol) by esterification. J. Mol. Catal. A: Chem. 2004, 223,
155−159. (b) Rashed, M. N.; Siddiki, S. M. A. H.; Touchy, A. S.;
Jamil, M. A. R.; Poly, S. S.; Toyao, T.; Maeno, Z.; Shimizu, K.-i. Direct
Phenolysis Reactions of Unactivated Amides into Phenolic Esters
Promoted by a Heterogeneous CeO2 Catalyst. Chem. - Eur. J. 2019,
25, 10594−10605. (c) Zhang, L.; Zhang, G.; Zhang, M.; Cheng, J.
Cu(OTf)2-Mediated Chan-Lam Reaction of Carboxylic Acids to
Access Phenolic Esters. J. Org. Chem. 2010, 75, 7472−7474. (d) Roy,
H. N.; Mamun, A. H. A. Regiospecific Phenyl Esterification to Some
Organic Acids Catalyzed by Combined Lewis Acids. Synth. Commun.
2006, 36, 2975−2981. (e) Xia, Z.-H.; Dai, L.; Gao, Z.-H.; Ye, S. N-
Heterocyclic carbene/photo-cocatalyzed oxidative Smiles rearrange-
ment: synthesis of aryl salicylates from O-aryl salicylaldehydes. Chem.
Commun. 2020, 56, 1525−1528.
(12) (a) Wang, S.-F.; Cao, X.-P.; Li, Y. Efficient Aryl Migration from
an Aryl Ether to a Carboxylic Acid Group to Form an Ester by
Visible-Light Photoredox Catalysis. Angew. Chem., Int. Ed. 2017, 56,
13809−13813. (b) Hossian, A.; Jana, R. Carboxyl radical-assisted 1,5-
aryl migration through Smiles rearrangement. Org. Biomol. Chem.
2016, 14, 9768−9779. (c) Gonzalez-Gomez, J. C.; Ramirez, N. P.;
Lana-Villarreal, T.; Bonete, P. A photoredox-neutral Smiles rearrange-
ment of 2-aryloxybenzoic acids. Org. Biomol. Chem. 2017, 15, 9680−
9684. (d) Xia, Z.-H.; Dai, L.; Gao, Z.-H.; Ye, S. N-Heterocyclic
Carbene/Photo-Cocatalyzed Oxidative Smiles Rearrangement: Syn-
thesis of Aryl Salicylates from O-aryl Salicylaldehydes. Chem.
Commun. 2020, 56, 1525−1528.
(13) (a) Kalmus, C. E.; Hercules, D. M. Mechanistic study of the
photo-Fries rearrangement of phenyl acetate. J. Am. Chem. Soc. 1974,
96, 449−456. (b) Mostafa, G. A Study of Probing the Mechanism of
Acylation Reactions and Fries Rearrangement by Polyphosphoric
Acid (PPA). Int. J. Appl. Chem. 2007, 3, 139−143. (c) Liu, T.; Yuan,
X.; Zhang, G.; Zeng, Y.; Chen, T.; Wang, G. Influence of
Coordinating Groups of Organotin Compounds on the Fries
Rearrangement of Diphenyl Carbonate. RSC Adv. 2019, 9, 28112−
28118.
̈
(2) (a) Kollar, L. Modern Carbonylation Methods; Wiley-VCH:
Weinheim, 2008. (b) Gabriele, B.; Mancuso, R.; Salerno, G. Oxidative
Carbonylation as a Powerful Tool for the Direct Synthesis of
Carbonylated Heterocycles. Eur. J. Org. Chem. 2012, 2012, 6825−
6839. (c) Gehrtz, P. H.; Hirschbeck, V.; Ciszek, B.; Fleischer, I.
Carbonylations of Alkenes in the Total Synthesis of Natural
Compounds. Synthesis 2016, 48, 1573−1596. (d) Bai, Y.; Davis, D.
C.; Dai, M. Natural Product Synthesis via Palladium-Catalyzed
Carbonylation. J. Org. Chem. 2017, 82, 2319−2328. (e) Dekleva, T.
W.; Forster, D. The rhodium-catalyzed carbonylation of linear
primary alcohols. J. Am. Chem. Soc. 1985, 107, 3565−3567.
(f) Haynes, A.; Maitlis, P. M.; Morris, G. E.; Sunley, G. J.; Adams,
H.; Badger, P. W.; Bowers, C. M.; Cook, D. B.; Elliott, P. I. P.;
Ghaffar, T.; Green, H.; Griffin, T. R.; Payne, M.; Pearson, J. M.;
Taylor, M. J.; Vickers, P. W.; Watt, R. J. Promotion of Iridium-
Catalyzed Methanol Carbonylation: Mechanistic Studies of the Cativa
Process. J. Am. Chem. Soc. 2004, 126, 2847−2861.
(3) Soloveichik, G. L. Oxidative Carbonylation: Diphenyl Carbo-
nate. In Liquid Phase Aerobic Oxidation Catalysis: Industrial
Applications and Academic Perspectives; Wiley-VCH Verlag GmbH &
Co. KGaA: Weinheim, Germany, 2016; pp 189−208 and references
cited therein.
(4) Komiya, K.; Fukuoka, S.; Aminaka, M.; Hasegawa, K.; Hachiya,
H.; Okamoto, H.; Watanabe, T.; Yoneda, H.; Fukawa, I.; Dozono, T.
In Green Chemistry: Designing Chemistry for the Environment; Anastas,
P. T., Williamson, T. C., Eds.; American Chemical Society:
Washington, DC, 1996; p 20.
(5) (a) Tundo, P.; Trotta, F.; Moraglio, G.; Ligorati, F. Continuous-
flow processes under gas-liquid phase-transfer catalysis (GL-PTC)
conditions: the reaction of dialkyl carbonates with phenols, alcohols,
and mercaptans. Ind. Eng. Chem. Res. 1988, 27, 1565−1571. (b) Ono,
Y. Dimethyl carbonate for environmentally benign reactions. Catal.
Today 1997, 35, 15−25. (c) Fu, Z. H.; Ono, Y. Two-step synthesis of
diphenyl carbonate from dimethyl carbonate and phenol using
catalysts. J. Mol. Catal. A: Chem. 1997, 118, 293−299. (d) Kim, W. B.;
Lee, J. S. Gas Phase Transesterification of Dimethylcarbonate and
Phenol over Supported Titanium Dioxide. J. Catal. 1999, 185, 307−
313. (e) Gong, J.; Ma, X.; Wang, S. Phosgene-free approaches to
catalytic synthesis of diphenyl carbonate and its intermediates. Appl.
Catal., A 2007, 316, 1−21.
(6) (a) Kim, W. B.; Joshi, U. A.; Lee, J. S. Making Polycarbonates
without Employing Phosgene: An Overview on Catalytic Chemistry
of Intermediate and Precursor Syntheses for Polycarbonate. Ind. Eng.
Chem. Res. 2004, 43, 1897−1914. (b) Biying, A. O.; Yuanting, K. T.;
Hosmane, N. S.; Zhu, Y. Ionic composite of palladium(II)/iron
bis(dicarbollide) for catalytic oxidative carbonylation in the formation
of diphenyl carbonate. J. Organomet. Chem. 2017, 849, 195−200.
(7) Hallgren, J. E.; Matthews, R. O. The Reactions of Carbon
Monoxide and Phenols Promoted by Palladium Complexes. J.
Organomet. Chem. 1979, 175, 135−142.
D
https://dx.doi.org/10.1021/acs.orglett.0c02133
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
(14) (a) Zhang, J.; Liu, J.-F.; Ugrinov, A.; Pillai, A. F. X.; Sun, Z.-M.;
Zhao, P. Methoxy-Directed Aryl-to-Aryl 1,3-Rhodium Migration. J.
Am. Chem. Soc. 2013, 135, 17270−17273. (b) Sharma, U.; Naveen,
T.; Maji, A.; Manna, S.; Maiti, D. Palladium-Catalyzed Synthesis of
Benzofurans and Coumarins from Phenols and Olefins. Angew. Chem.,
Int. Ed. 2013, 52, 12669−12673. (c) Dou, Y.; Kenry; Liu, J.; Jiang, J.;
Zhu, Q. Late-Stage Direct o-Alkenylation of Phenols by PdII-
Catalyzed C@H Functionalization. Chem. - Eur. J. 2019, 25, 6896−
6901. (d) Zhu, F.; Wang, Z.; Li, Y.; Wu, X.-F. Iridium-Catalyzed and
Ligand Controlled Carbonylative Synthesis of Flavones from Simple
Phenols and Internal Alkynes. Chem. - Eur. J. 2017, 23, 3276−3279.
(e) Zhu, F.; Li, Y.; Wang, Z.; Wu, X.-F. Iridium-Catalyzed
Carbonylative Synthesis of Chromenones from Simple Phenols and
Internal Alkynes at Atmospheric Pressure. Angew. Chem., Int. Ed.
2016, 55, 14151−14154. (f) Zhu, F.; Spannenberg, A.; Wu, X.-F.
Rhodium-Catalyzed Carbonylative Synthesis of Silyl-Substituted
Indenones. Chem. Commun. 2017, 53, 13149−13152. (g) Zhu, F.;
Wu, X.-F. Carbonylative Synthesis of 3-Substituted Thiochromenones
via Rhodium-Catalyzed [3 + 2 + 1] Cyclization of Different Aromatic
Sulfides, Alkynes and Carbon Monoxide. J. Org. Chem. 2018, 83,
̌
̌
13612−13617. (h) Al Mamari, H. H.; Stefane, B.; Zugelj, H. B.
Tetrahedron 2020, 76, 130925.
(15) Monodentate ligands such as PPh3 and PCy3 were also tried;
however, no desired product was found.
(16) Ming, J.; Hayashi, T. Rhodium-Catalyzed Arylzincation of
Alkynes: Ligand Control of 1,4-Migration Selectivity. Org. Lett. 2018,
20, 6188−6192.
(17) TEMPO-H was detected by GC-MS.
E
https://dx.doi.org/10.1021/acs.orglett.0c02133
Org. Lett. XXXX, XXX, XXX−XXX