Scalable Rhodium(III)-Catalyzed Aryl C?H Phosphorylation Enabled by Anodic Oxidation Induced Reductive Elimination

Article abstract of DOI:10.1002/anie.201909951

Transition metal catalyzed C?H phosphorylation remains an unsolved challenge. Reported methods are generally limited in scope and require stoichiometric silver salts as oxidants. Reported here is an electrochemically driven Rh^III-catalyzed aryl C?H phosphorylation reaction that proceeds through H₂ evolution, obviating the need for stoichiometric metal oxidants. The method is compatible with a variety of aryl C?H and P?H coupling partners and particularly useful for synthesizing triarylphosphine oxides from diarylphosphine oxides, which are often difficult coupling partners for transition metal catalyzed C?H phosphorylation reactions. Experimental results suggest that the mechanism responsible for the C?P bond formation involves an oxidation-induced reductive elimination process.

Full text of DOI:10.1002/anie.201909951

Angewandte
Communications
Chemie
International Edition: DOI: 10.1002/anie.201909951
German Edition: DOI: 10.1002/ange.201909951
Electrochemistry
Hot Paper
À
Scalable Rhodium(III)-Catalyzed Aryl C H Phosphorylation Enabled
by Anodic Oxidation Induced Reductive Elimination
Zheng-Jian Wu+, Feng Su+, Weidong Lin, Jinshuai Song, Ting-Bin Wen,* Hui-Jun Zhang,* and
Hai-Chao Xu*
À
Abstract: Transition metal catalyzed C H phosphorylation
remains an unsolved challenge. Reported methods are gener-
ally limited in scope and require stoichiometric silver salts as
oxidants. Reported here is an electrochemically driven RhIII-
À
catalyzed aryl C H phosphorylation reaction that proceeds
through H2 evolution, obviating the need for stoichiometric
metal oxidants. The method is compatible with a variety of aryl
À
À
C H and P H coupling partners and particularly useful for
synthesizing triarylphosphine oxides from diarylphosphine
oxides, which are often difficult coupling partners for transition
À
metal catalyzed C H phosphorylation reactions. Experimental
À
results suggest that the mechanism responsible for the C P
bond formation involves an oxidation-induced reductive
elimination process.
O
rganophosphorus compounds are widely utilized in
medicinal chemistry, materials science, and catalysis.[1]
À
Although transition metal catalyzed C H phosphorylation
is a straightforward and attractive approach for the construc-
À
tion of C P bonds, it is difficult to execute in practice because
of the strong propensity of phosphorus reagents to induce
catalyst poisoning through coordination.[2] Deactivation can
be avoided by either adding the phosphorus reagent slowly to
the reaction mixture (Scheme 1a)[3] or employing a-hydrox-
yalkylphosphonate as a masked, slow-releasing phosphonat-
ing reactant (Scheme 1b,c).[4,5] In addition, the installation of
a chelating directing group on benzoic acid derived substrates
has been shown to enable the use of H-phosphonates directly
in Cu-catalyzed reactions (Scheme 1d).[6] Despite these sig-
nificant advances,[7] the reported methods (Scheme 1a–d)
Scheme 1. Reaction design.
require stoichiometric amounts of silver salts as oxidants and
are inefficient in converting diarylphosphine oxides into
triarylphosphine oxides, which are precursors to triarylphos-
phine ligands.[8]
Organic electrochemistry is increasingly viewed as an
attractive, environmentally friendly synthetic strategy as it
requires no sacrificial oxidizing or reducing reagents and
instead uses electricity to promote redox transformations.[9] In
this context, the merger of electrochemistry with transition
[*] Z.-J. Wu,[+] F. Su,[+] W. Lin, Prof. Dr. T.-B. Wen, Dr. H.-J. Zhang,
Prof. Dr. H.-C. Xu
College of Chemistry and Chemical Engineering, Xiamen University
Xiamen 361005 (P. R. China)
E-mail: chwtb@xmu.edu.cn
meghjzhang@xmu.edu.cn
haichao.xu@xmu.edu.cn
Homepage: http://chem.xmu.edu.cn/groupweb/hcxu/
Z.-J. Wu,[+] Prof. Dr. H.-C. Xu
State Key Laboratory of Physical Chemistry of Solid Surfaces,
Laboratory of Chemical Biology of Fujian Province,iChEM, Xiamen
University, Xiamen 361005 (P. R. China)
À
metal catalyzed C H activation provides a powerful tool for
À
the development of sustainable C H functionalization reac-
tions.[10] Recently, many elegant examples of electrochemi-
À
cally driven transition metal catalyzed C H functionaliza-
tions have been reported,[11,12] including a Pd-catalyzed C H
À
phosphorylation reaction[11l] and a few Rh -catalyzed C C
III
À
cross-coupling reactions.[12] Herein, we describe an unprece-
dented RhIII-catalyzed electrochemical phosphorylation of
À
aryl C H bonds that can be used to efficiently synthesize
Dr. J. Song
triarylphosphine oxides from diarylphosphine oxides. Exper-
College of Chemistry and Molecular Engineering, Zhengzhou
University, Zhengzhou 450001 (P. R. China)
À
imental results suggest that the mechanism of the C P bond
[+] These authors contributed equally to this work.
formation in our method involves oxidation-induced reduc-
tive elimination rather than the RhIII/RhI catalytic cycle that
has previously been proposed for similar transformations with
chemical oxidants.[5]
Supporting information and the ORCID identification number(s) for
the author(s) of this article can be found under:
https://doi.org/10.1002/anie.201909951.
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We began our studies by first optimizing electrochemical
conditions for the phosphorylation of N-(2-pyridyl)aniline (1)
with diphenylphosphine oxide (2), a reaction which has not
been reported previously. The electrosynthesis was per-
formed in an undivided cell (a three-necked round-bottomed
flask) equipped with a reticulated vitreous carbon (RVC)
anode and a platinum plate cathode. The optimal results were
obtained at reflux (658C) and a constant current of 3 mA,
with a reaction mixture consisting of Cp*Rh(OAc)2 (5 mol%)
as the catalyst, KPF6 (1 equiv) as the supporting salt, and
MeOH as the solvent (Table 1). Under these reaction
para-position with a wide range of electronically diverse
functional groups, including Me (4), tBu (5), Cl (6), Br (7),
CO2Me (8), and OCF3 (9). meta-Substitution resulted in
regioselective phosphorylation at the sterically less hindered
site (10–13). Other aryl systems, such as N-(2-pyridyl)indoline
(see product 14) and N-(2-pyrimidyl)aniline (15) were also
tolerated, but O-(2-pyridyl)phenol bearing a weaker coordi-
nating directing group failed to react (16) because 2 inhibited
À
C H activation. Pyridine itself was found to be an excellent
À
directing group for the C H phosphorylation of benzene ring
(17), thiophene (18) and benzofuran (19). In fact, 2-phenyl-
pyridine could react at room temperature to afford 17 in 74%
yield. In addition to pyridine, many other heterocyclic
moieties commonly present in bioactive compounds, such as
pyrazole (20), pyridazine (21), purines (22–25), and pyrrolo-
pyrimidine (26), were also effective DGs. Notably, a cyclic
Table 1: Optimization of reaction conditions.[a]
À
ketimine was also effective in directing ortho C H phosphor-
ylation (27), and it enabled convenience functionalization of
benzodiazepine drugs such as diazepam (28), halazepam (29),
and prazepam (30).
Entry
Deviation from standard conditions
Yield [%][b]
The scope with respect to the phosphorus coupling
1
2
3
none
under argon
reaction at RT
75 (9)
71 (12)
0 (62)
À
partner was next examined (Scheme 2). With 1 as the C H
donor, the reaction tolerated a diverse array of diphenyl-
phosphine oxides bearing two functionalized aryl groups,
each with an OMe (31), tBu (32), or Cl (33) at the para-
position, an OPh (34) at the meta-position, or with Me groups
at the meta- or ortho-positions (35, 36). The NH-linked
pyridine was a less efficient DG for the synthesis of
arylphosphonates employing H-phosphonates as the phos-
phorus reagent. While the N-(2-pyridyl)aniline substrate
bearing an electron-donating OMe afforded the correspond-
ing product 37 in 74% yield, the reaction of an N-(2-
pyridyl)aniline derivative carrying an unsubstituted (38) or
Br-substituted (39) phenyl group at the same position
proceeded with substantially lower efficiency. In contrast,
aryl substrates bearing a more effective DG could be
efficiently phosphorylated by H-phosphonates (40–42),
isopropyl(phenyl)phosphine oxide (43), and even the chal-
lenging dialkylphosphine oxides (44–47).
4
5
6
7
8
9
10
11
12
13
14
15
no [Rh] catalyst
no electricity
0 (<5)
0 (97)[c]
<5 (54)
0 (30)
[Cp*RhCl2]2 (2.5 mol%), KOAc (2 equiv)
[Cp*IrCl2]2 (2.5 mol%), KOAc (2 equiv)
[Cp*Rh(MeCN)3](SbF6)2 (5 mol%)
EtOH as the solvent
tAmOH/H2O (3:1) as the solvent
5 mA
69
18 (54)
43 (37)[c]
68 (10)
57 (12)
<5 (69)
<5 (20)
69 (5)
10 mA
Pt plate anode (1 cmꢀ1 cm)
graphite rod anode
1.2 equiv of 2
[a] Reaction conditions: undivided cell, 1 (0.3 mmol), 2 (0.54 mmol),
MeOH (6 mL), air, 2.5 FmolÀ1 (based on 1). [b] Yield of isolated product.
Recovered unreacted 1 is shown within parentheses. [c] Yield determined
by 1H NMR analysis using 1,3,5-trimethoxybenzene as the internal
standard.
À
The electrochemical C H phosphorylation reaction could
conditions, the desired phosphorylation product 3 was
isolated in 75% yield (entry 1). Similar results were obtained
when the reaction was conducted under argon (entry 2).
Heating (entry 3), the Rh catalyst (entry 4) and electricity
be easily scaled up to gram and decagram scales as
demonstrated with the synthesis of 45, 50, and 17
(Scheme 3). The amounts of Rh catalyst, phosphorus
reagents, and KPF6 were decreased to reduce cost and
facilitate product isolation. The pyridyl group in 3 could be
removed by methylating the pyridyl nitrogen with MeOTf,
followed by nucleophilic replacement with hydrazine, to
furnish the corresponding free aniline 50.
À
(entry 5) are all indispensable for the C H phosphorylation
of 1. Further evaluation of different catalysts revealed that
Cp*Rh(OAc)2 can be replaced with [Cp*Rh(MeCN)3](SbF6)2
(entry 8) but not with [Cp*RhCl2]2 (entry 6) or [Cp*IrCl2]2
(entry 7), suggesting that the acetate ligands were not
required. Meanwhile, decreased formation of 3 was observed
when the reaction was conducted in another solvent such as
EtOH (entry 9) or tAmOH/H2O (entry 10), at a higher
current density (entries 11 and 12),[13] or with a different
type of anode such as Pt plate (entry 13) or graphite rod
(entry 14). Reducing the amount of 2 to 1.2 equivalents
(entry 15) only led to a slight decline in the yield of 3 (69%).
We next evaluated the coupling of 2 with various aryl
substrates (Scheme 2). The results demonstrated that the
phenyl ring of N-(2-pyridyl)aniline can be substituted at its
Our mechanistic studies indicated that 1 underwent rapid
H–D exchange in CD3OD in the presence of the RhIII-
catalyst, even at room temperature, without the need for
electric current (Scheme 4a). Furthermore, the reaction of
1 with 2 in CD3OD resulted in the formation of deuterated
1 and 3, both of which were deuterated at the ortho-position.
À
These findings suggested that activation of the ortho C H
bond in the aryl substrate was reversible under the reaction
conditions that we employed. Competition experiments (52
vs. 53) found the phosphorylative coupling reaction to favor
electron-rich aryl substrate over electron-poor ones, and 2
2
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À
Scheme 2. Scope of the electrochemical aryl C H phosphorylation. Reaction conditions: same as those used in Table 1, entry 1. Yields of isolated
products are reported. [a] Reaction with 10 mA. [b] Reaction at RT. [c] Reaction for 10 h (3.7 FmolÀ1). [d] [Cp*Rh(MeCN)3](SbF6)2 (5 mol%) as
catalyst.
ature (Scheme 4d). These results provided compelling evi-
À
dence that the C P bond was formed through oxidation-
induced reductive elimination.[14]
À
A possible mechanism for the electrochemical C H
phosphorylation reaction is shown in Scheme 4e using the
À
synthesis of 17 as an example. The ortho C H bond of 2-
phenylpyridine undergoes facile and reversible cyclorhoda-
tion to afford the rhodacycle 57. Ligand exchange between 57
and 2 affords the more oxidizable organometallic complex
58,[15] which then undergoes oxidation-induced reductive
À
elimination to generate the C H phosphorylation product
17 and either a RhIII or RhII complex depending on the
oxidation state of 59. It is currently unclear how many
electrons 58 loses prior to the reductive elimination. At the
cathode, protons are reduced to generate H2, obviating the
need for external electron or proton acceptors.
In summary, we have developed an electricity-powered,
Scheme 3. Reaction scale up.
III
À
Rh -catalyzed aryl C H phosphorylation reaction. The
electrochemical reactions are flexibly scalable and proceed
over diethylphosphite (54) and dibenzylphosphine oxide (55;
through H2 evolution. The method is compatible with
a diverse range of arenes and phosphorous reagents, and
allows facile access to various triarylphosphine oxide deriv-
atives. Anodic oxidation effectively promotes reductive
À
Scheme 4b). To probe the mechanism for C P bond forma-
tion, we prepared, under stoichiometric conditions, the
organometallic complexes 57 and 58, which were effective
catalysts for the coupling reaction of 51 with 2 (Scheme 4c).
Though stable in refluxing methanol, 58 reacted to afford the
phosphine oxide 17 when electrolyzed, even at room temper-
À
elimination of a Rh-complex to form the C P bond. Such
a mechanistic paradigm should be useful in developing new
Rh-catalyzed oxidative transformations.
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Scheme 4. Mechanistic studies and proposal.
O. A. Reutov, J. Organomet. Chem. 1980, 202, C58 – C60; c) Y.
Kuninobu, T. Yoshida, K. Takai, J. Org. Chem. 2011, 76, 7370 –
7376.
Acknowledgements
Financial support of this research from MOST
(2016YFA0204100), NSFC (Nos. 21672178, 21572188,
21772162), the Fundamental Research Funds for the Central
Universities, and Program for Changjiang Scholars and
Innovative Research Team in University.
[3] C.-G. Feng, M. Ye, K.-J. Xiao, S. Li, J.-Q. Yu, J. Am. Chem. Soc.
2013, 135, 9322 – 9325.
[4] C. Li, T. Yano, N. Ishida, M. Murakami, Angew. Chem. Int. Ed.
2013, 52, 9801 – 9804; Angew. Chem. 2013, 125, 9983 – 9986.
[5] M. Min, D. Kang, S. Jung, S. Hong, Adv. Synth. Catal. 2016, 358,
1296 – 1301.
[6] S. Wang, R. Guo, G. Wang, S.-Y. Chen, X.-Q. Yu, Chem.
Commun. 2014, 50, 12718 – 12721.
Conflict of interest
À
[7] C H-phosphorylation of electron-rich (hetero)arenes has been
reported and usually proceeds through a radical mechanism:
a) X.-J. Mu, J.-P. Zou, Q.-F. Qian, W. Zhang, Org. Lett. 2006, 8,
5291 – 5293; b) H.-J. Zhang, W. Lin, Z. Wu, W. Ruan, T.-B. Wen,
Chem. Commun. 2015, 51, 3450 – 3453; c) P. Peng, L. Peng, G.
Wang, F. Wang, Y. Luo, A. Lei, Org. Chem. Front. 2016, 3, 749 –
752; d) L. Niu, J. Liu, H. Yi, S. Wang, X.-A. Liang, A. K. Singh,
C.-W. Chiang, A. Lei, ACS Catal. 2017, 7, 7412 – 7416.
The authors declare no conflict of interest.
À
Keywords: C H activation · electrochemistry · oxidation ·
phosphorylation · rhodium
[8] Y. Li, L.-Q. Lu, S. Das, S. Pisiewicz, K. Junge, M. Beller, J. Am.
Chem. Soc. 2012, 134, 18325.
[9] Selected recent reviews on electroorganic synthesis: a) E. J.
Horn, B. R. Rosen, P. S. Baran, ACS Cent. Sci. 2016, 2, 302 – 308;
b) M. Yan, Y. Kawamata, P. S. Baran, Chem. Rev. 2017, 117,
13230 – 13319; c) M. Yan, Y. Kawamata, P. S. Baran, Angew.
Chem. Int. Ed. 2018, 57, 4149 – 4155; Angew. Chem. 2018, 130,
4219 – 4225; d) S. R. Waldvogel, S. Lips, M. Selt, B. Riehl, C. J.
Kampf, Chem. Rev. 2018, 118, 6706 – 6765; e) Q.-L. Yang, P.
Fang, T.-S. Mei, Chin. J. Chem. 2018, 36, 338 – 352; f) S. Tang, Y.
Liu, A. Lei, Chem 2018, 4, 27 – 45; g) R. Francke, R. D. Little,
Chem. Soc. Rev. 2014, 43, 2492 – 2521; h) J. Yoshida, K. Kataoka,
R. Horcajada, A. Nagaki, Chem. Rev. 2008, 108, 2265 – 2299;
[1] a) C. S. Demmer, N. Krogsgaard-Larsen, L. Bunch, Chem. Rev.
2011, 111, 7981 – 8006; b) K. J. Gagnon, H. P. Perry, A. Clear-
field, Chem. Rev. 2012, 112, 1034 – 1054; c) C. Queffꢀlec, M.
Petit, P. Janvier, D. A. Knight, B. Bujoli, Chem. Rev. 2012, 112,
3777 – 3807; d) W. Tang, X. Zhang, Chem. Rev. 2003, 103, 3029 –
3070; e) M. P. Carroll, P. J. Guiry, Chem. Soc. Rev. 2014, 43, 819 –
833; f) T. D. Baguley, H.-C. Xu, M. Chatterjee, A. C. Nairn, P. J.
Lombroso, J. A. Ellman, J. Med. Chem. 2013, 56, 7636 – 7650.
[2] Examples of stoichiometric and intramolecular reactions:
a) V. A. Stepanova, V. V. Dunina, I. P. Smoliakova, Organo-
metallics 2009, 28, 6546 – 6558; b) V. I. Sokolov, L. L. Troitskaya,
4
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i) K. D. Moeller, Chem. Rev. 2018, 118, 4817 – 4833; j) J. E.
L. Zeng, S. Tang, A. Lei, J. Am. Chem. Soc. 2018, 140, 4195 –
Nutting, M. Rafiee, S. S. Stahl, Chem. Rev. 2018, 118, 4834 –
4885; k) A. Wiebe, T. Gieshoff, S. Mçhle, E. Rodrigo, M.
Zirbes, S. R. Waldvogel, Angew. Chem. Int. Ed. 2018, 57, 5594 –
5619; Angew. Chem. 2018, 130, 5694 – 5721; l) S. Mçhle, M.
Zirbes, E. Rodrigo, T. Gieshoff, A. Wiebe, S. R. Waldvogel,
Angew. Chem. Int. Ed. 2018, 57, 6018 – 6041; Angew. Chem. 2018,
130, 6124 – 6149; m) J. Yoshida, A. Shimizu, R. Hayashi, Chem.
Rev. 2018, 118, 4702 – 4730; n) Y. Jiang, K. Xu, C. Zeng, Chem.
Rev. 2018, 118, 4485 – 4540; o) G. S. Sauer, S. Lin, ACS Catal.
2018, 8, 5175 – 5187; p) H. Wang, X. Gao, Z. Lv, T. Abdelilah, A.
Lei, Chem. Rev. 2019, 119, 6769 – 6787.
4199; i) A. Shrestha, M. Lee, A. L. Dunn, M. S. Sanford, Org.
Lett. 2018, 20, 204 – 207; j) K. Takamatsu, Y. Hayashi, S.
Kawauchi, K. Hirano, M. Miura, ACS Catal. 2019, 9, 5336 –
5344; k) Y. Kawamata, J. C. Vantourout, D. P. Hickey, P. Bai,
L. Chen, Q. Hou, W. Qiao, K. Barman, M. A. Edwards, A. F.
Garrido-Castro, J. N. deGruyter, H. Nakamura, K. Knouse, C.
Qin, K. J. Clay, D. Bao, C. Li, J. T. Starr, C. Garcia-Irizarry, N.
Sach, H. S. White, M. Neurock, S. D. Minteer, P. S. Baran, J. Am.
Chem. Soc. 2019, 141, 6392 – 6402; l) T. V. Grayaznova, Y. B.
Dudkina, D. R. Islamov, O. N. Kataeva, O. G. Sinyashin, D. A.
Vicic, Y. H. Budnikova, J. Organomet. Chem. 2015, 785, 68 – 71.
[12] a) W.-J. Kong, L. H. Finger, J. C. A. Oliveira, L. Ackermann,
Angew. Chem. Int. Ed. 2019, 58, 6342 – 6346; Angew. Chem.
2019, 131, 6408 – 6412; b) Y. Qiu, W.-J. Kong, J. Struwe, N.
Sauermann, T. Rogge, A. Scheremetjew, L. Ackermann, Angew.
Chem. Int. Ed. 2018, 57, 5828 – 5832; Angew. Chem. 2018, 130,
5930 – 5934; c) Y. Qiu, A. Scheremetjew, L. Ackermann, J. Am.
Chem. Soc. 2019, 141, 2731 – 2738.
[10] Selected reviews: a) N. Sauermann, T. H. Meyer, Y. Qiu, L.
Ackermann, ACS Catal. 2018, 8, 7086 – 7103; b) C. Ma, P. Fang,
T.-S. Mei, ACS Catal. 2018, 8, 7179 – 7189; c) T. H. Meyer, L. H.
Finger, P. Gandeepan, L. Ackermann, Trends Chem. 2019, 1, 63 –
76; d) K.-J. Jiao, C.-Q. Zhao, P. Fang, T.-S. Mei, Tetrahedron Lett.
2017, 58, 797 – 802; e) M. D. Kꢁrkꢁs, Chem. Soc. Rev. 2018, 47,
5786 – 5865; f) Y. Qiu, J. Struwe, L. Ackermann, Synlett 2019, 30,
1164 – 1173.
[11] a) Q.-L. Yang, Y.-Q. Li, C. Ma, P. Fang, X.-J. Zhang, T.-S. Mei, J.
Am. Chem. Soc. 2017, 139, 3293 – 3298; b) F. Xu, Y.-J. Li, C.
Huang, H.-C. Xu, ACS Catal. 2018, 8, 3820 – 3824; c) Q.-L. Yang,
X.-Y. Wang, J.-Y. Lu, L.-P. Zhang, P. Fang, T.-S. Mei, J. Am.
Chem. Soc. 2018, 140, 11487 – 11494; d) C. Amatore, C. Cam-
moun, A. Jutand, Adv. Synth. Catal. 2007, 349, 292 – 296; e) F.
Kakiuchi, T. Kochi, H. Mutsutani, N. Kobayashi, S. Urano, M.
Sato, S. Nishiyama, T. Tanabe, J. Am. Chem. Soc. 2009, 131,
11310 – 11311; f) S. Tang, D. Wang, Y. Liu, L. Zeng, A. Lei, Nat.
Commun. 2018, 9, 798; g) Y. Qiu, C. Tian, L. Massignan, T.
Rogge, L. Ackermann, Angew. Chem. Int. Ed. 2018, 57, 5818 –
5822; Angew. Chem. 2018, 130, 5920 – 5924; h) X. Gao, P. Wang,
[13] Competitive oxidation of 1 was observed at high current density:
E. Feng, Z.-W. Hou, H.-C. Xu, Chin. J. Org. Chem. 2019, 39,
1424 – 1428.
[14] a) L. Li, W. W. Brennessel, W. D. Jones, J. Am. Chem. Soc. 2008,
130, 12414 – 12419; b) J. Kim, K. Shin, S. Jin, D. Kim, S. Chang, J.
Am. Chem. Soc. 2019, 141, 4137 – 4146; c) K. Shin, Y. Park, M.-
H. Baik, S. Chang, Nat. Chem. 2018, 10, 218.
[15] See the Supporting Information for cyclic voltammetry studies.
Manuscript received: August 6, 2019
Accepted manuscript online: August 28, 2019
Version of record online: && &&, &&&&
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Z.-J. Wu, F. Su, W. Lin, J. Song, T.-B. Wen,*
H.-J. Zhang,* H.-C. Xu*
&&&& — &&&&
À
Scalable Rhodium(III)-Catalyzed Aryl C
H Phosphorylation Enabled by Anodic
Oxidation Induced Reductive Elimination
Electric cell: Reported herein is an elec-
ylphosphine oxides from diarylphosphine
oxides. Experimental results suggest that
trochemically driven RhIII-catalyzed aryl
À
À
C H phosphorylation reaction which
proceeds through H2 evolution. The
method is compatible with a variety of
the mechanism responsible for the C P
bond formation involves an oxidation-
induced reductive elimination process.
DG=directing group.
À
À
aryl C H and P H coupling partners and
particularly useful for synthesizing triar-
6
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