Rhodium(III)-catalyzed in situ oxidizing directing group- assisted c-h bond activation and olefination: A route to 2-vinylanilines

Article abstract of DOI:10.1002/adsc.201400791

A new and efficient method for the synthesis of 2-vinylanilines from the reaction of arylhydrazine hydrochlorides with alkenes and diethyl ketone via a rhodium-catalyzed C-H activation is described. The oxidant-free olefination reaction involves the in situ generation of an -N-N=CR¹R² moiety as the oxidizing directing group thus providing an easy access to 2-vinylanilines.

Full text of DOI:10.1002/adsc.201400791

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DOI: 10.1002/adsc.201400791
Rhodium(III)-Catalyzed in situ Oxidizing Directing Group-
À
Assisted C H Bond Activation and Olefination: A Route to
2-Vinylanilines
Krishnamoorthy Muralirajan,a Radhakrishnan Haridharan,a Sekar Prakash,a
and Chien-Hong Chenga,*
a
Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
Fax : (+886)-3572-4698; e-mail: chcheng@mx.nthu.edu.tw
Received: August 10, 2014; Revised: November 2, 2014; Published online: && &&, 0000
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201400791.
Abstract: A new and efficient method for the syn-
thesis of 2-vinylanilines from the reaction of arylhy-
drazine hydrochlorides with alkenes and diethyl
À
ketone via a rhodium-catalyzed C H activation is
described. The oxidant-free olefination reaction in-
1
2
À À
volves the in situ generation of an N N=CR R
moiety as the oxidizing directing group thus provid-
ing an easy access to 2-vinylanilines.
À
Keywords: alkenes; C H activation; in situ oxidiz-
ing directing group; rhodium; 2-vinylanilines
Substituted 2-vinylanilines are important intermedi-
ates for the synthesis of biologically related heterocy-
clic compounds.[1] Notably various metal-catalyzed
synthetic pathways have been found for the synthesis
Scheme 1. Strategies for the synthesis of 2-vinylanilines.
of 2-vinylaniline derivatives, namely the Suzuki,[2a] a ketone in the presence of a rhodium catalyst. The
Stille,[2b] Mizoroki–Heck couplings[2c] and some reduc- reaction provides an effective method for the synthe-
tion[2d,e] reactions. However, these methods generally sis of 2-vinylaniline derivatives via rhodium-catalyzed
À
require multiple steps, pre-functionalized substrates C H activation. The catalytic reaction does not re-
and harsh reaction conditions.[2f–h] Furthermore, the quire an external oxidant, instead, the in situ generat-
costs of the reported starting materials and deriva- ed hydrazone from the ketone and arylhydrazine acts
tives are high and they are also less stable as an oxidizing directing group. In addition, the reac-
(Scheme 1).
tion uses directly the unprotected arylhydrazine salts
In general, metal-catalyzed arene cross dehydro- and proceeds smoothly to give 2-vinylanilines in one
À
genative olefination through C H activation reactions step. It is noteworthy that the previously reported
required an external metal or non-metal oxidant to ortho-olefination reactions of N-arylacetamides with
regenerate the active catalyst.[3,4] However, several alkenes gave 2-vinylanilides.[7a–d] Further hydrolysis of
À
N O containing directing groups which also act as in- these products is required to form the corresponding
ternal oxidants[5] for the metal-catalyzed annulati- 2-vinylaniline. Thus, our reaction appears to be the
ACHTUNGTRENNUNG
on[5a–i] and olefination[5j–s] reactions through C H acti- first example of the synthesis of 2-vinylanilines via C
À
À
vation have recently been developed.
H olefination using an in situ generated oxidizing di-
À
Our continuing interest in developing new C H ac- recting group. Very recently, we reported an in situ
tivation reactions[6] has prompted us to examine the generated redox neutral group directed C H activa-
À
reaction of arylhydrazine hydrochlorides, alkenes and tion/annulation towards the synthesis of indoles from
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Krishnamoorthy Muralirajan et al.
Table 1. Screening for the reaction conditions.[a,b]
Table 2. Reaction scope of various substituted styrenes.[a,b]
Entry
Solvent
3
Base
Yield (4a [%])
1
2
3
4
5
6
7
8
DMF
3b
3b
3b
3b
3b
3b
3b
3a
3c
3d
3e
3f
NaOAc
NaOAc
NaOAc
NaOAc
NaOAc
KOAc
CsOAc
NaOAc
NaOAc
NaOAc
NaOAc
NaOAc
NaOAc
26
54
83
93 (89)
5
79
65
80
62
67
78
14
61
t-BuOH
MeOH
EtOH
DCE
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
9
10
11
12
13
3g
[a]
[a]
Conditions A: unless otherwise mentioned, all reactions
Conditions A: unless otherwise mentioned, all reactions
were carried out using 1a (1.00 mmol), 2a (2.00 mmol),
[RhCp*Cl2]2 (2 mol%), base (1.50 mmol), AcOH
(3.00 mmol), 3 (1.20 mmol) and solvent (2 mL) at 1008C
for 20 h under N2.
were carried out using 1 (1.00 mmol), 2 (2.00 mmol),
[RhCp*Cl2]2 (2 mol%), NaOAc (1.50 mmol), AcOH
(3.00 mmol), 3b (1.20 mmol) and EtOH (2 mL) at 1008C
for 20 h.
[b]
[b]
Isolated yield.
Yields were determined by the 1H NMR integration
method; the value in the parenthesis is the isolated yield.
EtOH afforded the highest yield, while other solvents
arylhydrazine hydrochlorides and alkynes. The in situ including DMF, t-BuOH, MeOH and DCE gave only
generated hydrazone acted as an internal oxidant to moderate yields (5–83%, entries 1–3, 5). Of the bases
regenerate the rhodium active catalyst.[7j] Several rho- employed, NaOAc afforded the highest yield
À
dium-catalyzed C H bond activation reactions other (entry 4). KOAc and CsOAc were less effective pro-
[7e–m]
[5]
À
À
than olefination using an N N
or N O moiety viding product 4a in 79 and 65% yields, respectively
as an internal oxidizing group also are known.
(entry 6 and 7). The ketone employed also showed
The effect of reaction conditions on the yield of a significant influence on the yield. Acetone (3a) af-
product 4a is summarized in Table 1. In the absence forded 4a in 80% yield, while diethyl ketone gave 4a
of rhodium complex, AcOH or base, no product 4a in 93% (89% isolated) yield.[8] The other ketones 3c–
was observed. In the effort to find suitable reaction e were also effective, but gave 4a in lower yields (en-
conditions, we observed that the reaction of phenylhy- tries 9–11). In addition, we tested the activity of alde-
drazine hydrochloride (1a, 1.00 mmol), diethyl ketone hydes such as benzaldehyde (3f) and pentanal (3g) as
(3b, 1.20 mmol) with styrene (2a, 2.00 mmol) in the a substitute for ketone in the catalytic reaction. The
presence of 2 mol% of [RhCp*Cl2]2, 1.50 mmol of yields vary substantially from 14 to 61% (entries 12
NaOAc and 3.00 mmol of AcOH in EtOH at 1008C and 13).
under N2 for 20 h gave 2-styrylaniline 4a in 93% yield
With the optimized reaction conditions A in hand,
(conditions A, Table 1, entry 4). Both the solvent and we examined the scope of the ortho-vinylation reac-
base used in the catalytic reaction are important to tion using differently substituted arylhydrazine hydro-
obtain high yields. Among the solvents examined, chlorides (1a–j) and styrene (2a) (Table 2). All of the
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Rhodium(III)-Catalyzed in situ Oxidizing Directing Group-Assisted C H
Table 3. Reaction scope of various electron deficient al-
reactions afforded the desired 2-vinylanilines 4a–j in
the presence of the external promoter diethyl ketone.
Phenylhydrazine hydrochlorides with a para-substitu-
ent, either electron-donating or electron-withdrawing,
gave the expected products in 80–88% yields. meta-
Substituted arylhydrazine hydrochlorides 1i and 1j
were also tested for the reactivity with 2a affording
highly regioselectively the products 4i and 4j, respec-
tively, in 77–79% yields.
kenes.[a,b]
In addition to 2a, other arylalkenes (2b–g) having
Me, MeO, F, Cl, Br and CH2CN substituents on the
aryl rings also reacted with 1a under the standard re-
action conditions to afford highly functionalized 2-vi-
nylaniline derivatives 4k–p in good to excellent yields.
Similarly, meta-substituted styrenes 2h–k with 3-Me,
3-NO2, 3-CO2Et and 3-CN substituents on the phenyl
ring, respectively, reacted with 1a to afford the corre-
sponding products 4q–t in 73–83% yields. The present
reaction appears compatible with a broad scope of
functional groups on the aryl rings of 1 and 2.
Unfortunately, the catalytic reaction conditions A
was ineffective for the ortho-vinylation of arylhydra-
zines with electron-deficient alkenes such as acrylates,
acrylonitrile and vinyl ketones to give the correspond-
ing 2-vinylanilines. As a result, we further optimized
the reaction conditions for activated alkenes. To our
delight, we found that by simply changing ethanol to
dichloroethane (DCE) as a solvent, the vinylation
became possible. Thus, the reaction of phenylhydra-
zine 1a (1.00 mmol) and ketone 3b (1.50 mmol) with
ethyl acrylate (2n, 2.00 mmol) in the presence of
2 mol% of [RhCp*Cl2]2, NaOAc (1.50 mmol) and
AcOH (3.00 mmol) in DCE (2 mL) at 808C under N2
for 18 h gave (E)-ethyl 3-(2-aminophenyl)acrylate 5c
in 78% isolated yield. Under the same reaction condi-
tions (conditions B), various acrylates and acryla-
mides also reacted smoothly with 1a to afford ortho-
vinylated products 5a–j in 68–79% yields as displayed
in Table 3. Similarly, the reactions with diethyl vinyl-
phosphonate and acrylonitrile also proceeded effi-
ciently to give vinyl functional anilines 5k and 5l, re-
spectively, in moderate yields. Finally, the substrate
[a]
Conditions B: unless otherwise mentioned, all reactions
were carried out using 1 (1.00 mmol), 2 (2.00 mmol),
[RhCp*Cl2]2 (2 mol%), NaOAc (1.50 mmol), AcOH
(3.00 mmol), 3b (1.50 mmol) and DCE (2 mL) at 808C
for 18 h.
[b]
Isolated yield.
scope of arylhydrazines (1) was inspected. Both elec- nylsilane, vinyl borate and vinyl ether did not undergo
tron-donating and electron-withdrawing groups on the expected vinylation reaction under both reaction
the phenyl ring of 1 appear compatible with the cata- conditions A or B.
lytic reaction. Thus, para-isopropyl- para-fluoro-,
On the basis of the optimization studies and the
para-chloro-, para-bromo-, ortho-methyl- and meta- chemistry reported previously,[3–5] a plausible mecha-
bromophenylhydrazines reacted smoothly with ethyl nism for this reaction using 1, 2 and 3b as the sub-
acrylate to afford the expected products 5m–r in 72– strates is proposed as shown in Scheme 2. The reac-
83% yields (Table 3). The role of solvent in the pres- tion is probably initiated by the reaction of 1 with 3b
ent reaction is still unclear. A possible reason that the to form hydrazone I. Then, facile cyclometalation of I
ortho-vinylation of arylhydrazines with electron-defi- with RhCp*(OAc)2 affords five-membered intermedi-
cient alkenes did not proceed well in ethanol could be ate II. Subsequently, alkene insertion occurred to
a relatively fast 1,4-addition of the amino group to form a seven-membered intermediate IV. The inter-
the electron-deficient alkenes. It should also be noted mediate then undergoes b-hydride elimination, fol-
that substituted acrylates such as methyl methacry- lowed by reductive elimination to give salt VI and
À
late, methyl (E)-but-2-enoate, methyl vinyl ketone, vi- Rh(I) species (VII). Insertion of the Rh(I) to the N
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Krishnamoorthy Muralirajan et al.
Scheme 2. A plausible reaction mechanism.
N bond[7e,h–j] in VI followed by protonation regener- tions (see the Supporting Information). As shown in
ates the active Rh(III) species and vinylaniline 4 or 5. Scheme 3, the reaction of I with 2n under the stan-
Intermediate I could be readily prepared from the dard conditions gave the expected o-vinylaniline 5c in
reaction of phenylhydrazine hydrochloride and dieth- 72% yield.[9] The omission of either HOAc or NaOAc
yl ketone. To support the proposed mechanism, I was in the reaction solution gave no product 5c (see the
allowed to react with 2n under various reaction condi- Supporting Information). The results are in agree-
Scheme 3. Mechanism-related experiments.
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Rhodium(III)-Catalyzed in situ Oxidizing Directing Group-Assisted C H
References
ment with those in Table 1 and support the proposed
mechanism in Scheme 2. It is noteworthy that
a HOAc/OAcÀ buffer medium is necessary for the
catalytic reaction to proceed and RhCp*(OAc)2, gen-
erated from [RhCp*Cl2]2 and NaOAc, is plausibly the
active catalyst.[10a,b] The NaCl precipitation appears to
be the driving force for the generation of
RhCp*(OAc)2.[7h,j] In the absence of ketone (3b) three
different 1,4-addition products along with the expect-
ed 5c were observed (Scheme 3). The results show
that 1,4-addition reactions became the preferred path-
way in the absence of ketone. To further understand
the reaction mechanism, deuterium isotope labeling
reactions were also investigated (see the Supporting
Information and Scheme 3). A 72% H/D exchange at
the ortho carbon of D5-1a was found (see the Sup-
[1] a) K. Butkovic, D. Vuk, Z. Marinic, J. Penic, M. Sin-
dler-Kulyk, Tetrahedron 2010, 66, 9356; b) S. W. Youn,
J. H. Bihn, Tetrahedron Lett. 2009, 50, 4598; c) A.
Ricci, (Ed.), Amino Group Chemistry, Wiley-VCH,
Weinheim, 2008.
[2] a) M. Shen, B. E. Leslie, T. G. Driver, Angew. Chem.
2008, 120, 5134; Angew. Chem. Int. Ed. 2008, 47, 5056;
b) K. Muniz, J. Am. Chem. Soc. 2007, 129, 14542; c) K.
Mennecke, W. Solodenko, A. Kirschning, Synthesis
2008, 1589; d) W. R. Bowman, A. J. Fletcher, P. J.
Lovell, J. M. Pedersen, Synlett 2004, 1905; e) M.
Gruber, S. Chouzier, K. Koehler, L. Djakovitch, Appl.
Catal. A. 2004, 265, 161; f) K. Kaneda, H. Kuwahara, T.
Imanaka, J. Mol. Catal. 1994, 88, L267; g) K. Song, S.
Kong, Q. Liu, W.-H. Sun, C. Redshaw, J. Organomet.
Chem. 2014, 751, 453; h) S. R. Borhade, S. B. Wagh-
mode, Tetrahedron Lett. 2008, 49, 3423; see also the
supporting information files of the cited articles.
[3] For selected reviews: a) T. Satoh, M. Miura, Chem.
Eur. J. 2010, 16, 11212; b) S. H. Cho, J. Y. Kim, J.
Kwak, S. Chang, Chem. Soc. Rev. 2011, 40, 5068;
c) F. W. Patureau, J. Wencel-Delord, F. Glorius, Aldri-
chimica Acta 2012, 45, 31; d) Y. Wu, J. Wang, F. Mao,
F. Y. Kwong, Chem. Asian J. 2014, 9, 26; e) J. W.
Delord, T. Drçge, F. Liu, F. Glorius, Chem. Soc. Rev.
2011, 40, 4740; f) G. Song, F. Wang, X. Li, Chem. Soc.
Rev. 2012, 41, 3651; g) D. A. Colby, A. S. Tsai, R. G.
Bergman, J. A. Ellman, Acc. Chem. Res. 2012, 45, 814.
[4] For selected examples of Rh-, Ru- and Pd-catalyzed
À
porting Information) indicating that the C H activa-
tion is reversible. In addition, the observed KIE value
À
k5c/kD -5c of 2.9 suggest that the C H bond cleavage
4
occurred in one of the product-forming steps.[11a,b]
In summary, we have successfully developed a rho-
À
dium-catalyzed hydrazine-assisted C H activation
and olefination reaction for the synthesis of unpro-
tected 2-vinylanilines. The hydrazone, in situ generat-
ed from arylhydrazine and ketone, acts as a directing
group and as an internal oxidant. A wide range of
arenes and alkenes can be used in this catalytic reac-
tion. The catalytic reaction appears to be the first ex-
ample for the synthesis of 2-vinylanilines using an in
À
C H olefination, see: a) N. Umeda, K. Hirano, T.
À
situ generated oxidizing directing group-assisted C H
activation as a key step.
Satoh, M. Miura, J. Org. Chem. 2009, 74, 7094; b) T.-J.
Gong, B. Xiao, Z.-J. Liu, J. Wan, J. Xu, D.-F. Luo, Y.
Fu, L. Liu, Org. Lett. 2011, 13, 3235; c) H. Li, Y. Li, X.-
S. Zhang, K. Chen, X. Wang, Z.-J. Shi, J. Am. Chem.
Soc. 2011, 133, 15244; d) F. W. Patureau, T. Besset, F.
Glorius, Angew. Chem. 2011, 123, 1096; Angew. Chem.
Int. Ed. 2011, 50, 1064; e) S. H. Park, J. Y. Kim, S.
Chang, Org. Lett. 2011, 13, 2372; f) C. Wang, H. Chen,
Z. Wang, J. Chen, Y. Huang, Angew. Chem. 2012, 124,
7354; Angew. Chem. Int. Ed. 2012, 51, 7242; g) L. Ac-
kermann, L. Wang, R. Wolfram, A. V. Lygin, Org. Lett.
2012, 14, 337; h) K. Padala, M. Jeganmohan, Org. Lett.
2012, 14, 1134; i) S. I. Kozhushkov, L. Ackermann,
Chem. Sci. 2013, 4, 886; j) K. M. Engle, D.-H. Wang, J.-
Q. Yu, Angew. Chem. 2010, 122, 6305; Angew. Chem.
Int. Ed. 2010, 49, 6169; k) A. Garcia-Rubia, B. Urones,
R. Gomez Arrayas, J. C. Carretero, Angew. Chem.
2011, 123, 11119; Angew. Chem. Int. Ed. 2011, 50,
10927; l) C. Wang, H. Ge, Chem. Eur. J. 2011, 17, 1437;
m) H.-L. Wang, R.-B. Hu, H. Zhang, A.-X. Zhou, S.-D.
Yang, Org. Lett. 2013, 15, 5302.
Experimental Section
General Procedure
A
1
sealed tube containing arylhydrazine hydrochloride
(1.00 mmol), arylalkene (2.00 mmol), [RhCp*Cl2]2
2
(2.0 mol%) and NaOAc (1.50 mmol) was evacuated and
purged with nitrogen gas three times. Then, EtOH (2.0 mL),
diethyl ketone 3b (1.20 mmol) and AcOH (3.00 mmol) were
sequentially added to the system via a syringe under a nitro-
gen atmosphere and the reaction mixture was allowed to stir
at 1008C for 20 h. When the reaction was complete, the mix-
ture was cooled and diluted with CH2Cl2 (10 mL). The mix-
ture was filtered through a celite pad and the celite pad was
washed with CH2Cl2 (50 mL). The filtrate was concentrated
and the residue was purified by column chromatography
(neutral aluminium oxide, hexane-EtOAc) to give the corre-
sponding pure olefination product 4.
[5] a) N. Guimond, C. Gouliaras, K. Fagnou, J. Am. Chem.
Soc. 2010, 132, 6908; b) N. Guimond, S. I. Gorelsky, K.
Fagnou, J. Am. Chem. Soc. 2011, 133, 6449; c) P. C.
Too, S. H. Chua, S. H. Wong, S. Chiba, J. Org. Chem.
2011, 76, 6159; d) T. K. Hyster, T. Rovis, Chem.
Commun. 2011, 47, 11846; e) X. Zhang, D. Chen, M.
Zhao, J. Zhao, A. Jia, X. Li, Adv. Synth. Catal. 2011,
353, 719; f) S. Rakshit, C. Grohmann, T. Besset, F. Glo-
rius, J. Am. Chem. Soc. 2011, 133, 2350; g) C. Kornhaa,
Acknowledgements
We thank the Ministry of Science and Technology of the Re-
public of China (NSC-102-2628M-007-005) for support of
this research.
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5
ÞÞ
These are not the final page numbers!

COMMUNICATIONS
Krishnamoorthy Muralirajan et al.
J. Li, L. Ackermann, J. Org. Chem. 2012, 77, 9190;
h) G. Liu, Y. Shen, Z. Zhou, X. Lu, Angew. Chem. Int.
Ed. 2013, 52, 6033; i) B. Li, H. Feng, S. Xu, B. Wang,
Chem. Eur. J. 2011, 17, 12573; j) B. Li, J. Ma, N. Wang,
H. Feng, S. Xu, B. Wang, Org. Lett. 2012, 14, 736; k) L.
Xu, Q. Zhu, G. Huang, B. Cheng, Y. Xia, J. Org. Chem.
2012, 77, 3017; l) T. K. Hyster, L. Knorr, T. R. Ward, T.
Rovis, Science 2012, 338, 500; m) B. Ye, N. Cramer, Sci-
ence 2012, 338, 504; n) J. M. Neely, T. Rovis, J. Am.
Chem. Soc. 2013, 135, 66; o) T. K. Hyster, K. E. Ruhl,
T. Rovis, J. Am. Chem. Soc. 2013, 135, 5364; p) Y.
Shen, G. Liu, Z. Zhou, X. Lu, Org. Lett. 2013, 15, 3366;
q) J. Wu, X. Cui, L. Chen, G. Jiang, Y. Wu, J. Am.
Chem. Soc. 2009, 131, 13888; r) Y. Tan, J. F. Hartwig, J.
Am. Chem. Soc. 2010, 132, 3676; s) P. C. Too, Y.-F.
Wang, S. Chiba, Org. Lett. 2010, 12, 5688.
Patureau, F. Glorius, J. Am. Chem. Soc. 2010, 132,
9982; c) R. Manikandan, M. Jeganmohan, Org. Lett.
2014, 16, 912; d) L. Ackermann, L. Wang, R. Wolfram,
A. V. Lygin, Org. Lett. 2012, 14, 728; e) D. Zhao, Z.
Shi, F. Glorius, Angew. Chem. Int. Ed. 2013, 52, 12426;
f) C. Wang, Y. Huang, Org. Lett. 2013, 15, 5294; g) B.
Liu, C. Song, C. Sun, S. Zhou, J. Zhu, J. Am. Chem.
Soc. 2013, 135, 16625; h) L. Zheng, R. Hua, Chem. Eur.
J. 2014, 20, 2352; i) S.-C. Chuang, P. Gandeepan, C.-H.
Cheng, Org. Lett. 2013, 15, 5750; j) K. Muralirajan, C.-
H. Cheng, Adv. Synth. Catal. 2014, 356, 1571; k) B. Liu,
Y. Fan, Y. Gao, C. Sun, C. Xu, J. Zhu, J. Am. Chem.
Soc. 2013, 135, 468; l) S. Han, Y. Shin, S. Sharma, N. K.
Mishra, J. Park, M. Kim, M. Kim, J. Jang, I. S. Kim,
Org. Lett. 2014, 16, 2494; m) J. Yao, R. Feng, C. Lin, Z.
Liu, Y. Zhang, Org. Biomol. Chem. 2014, 12, 5469.
[8] The effect of diethyl ketone on the yield of product 4a
is summarized in Table 1 in the Supporting Informa-
tion.
[6] a) K. Muralirajan, K. Parthasarathy, C.-H. Cheng,
Angew. Chem. 2011, 123, 4255; Angew. Chem. Int. Ed.
2011, 50, 4169; b) K. Muralirajan, K. Parthasarathy, C.-
H. Cheng, Org. Lett. 2012, 14, 4262; c) J. Jayakumar, K.
Parthasarathy, C.-H. Cheng, Angew. Chem. 2012, 124,
201; Angew. Chem. Int. Ed. 2012, 51, 197; d) J. Karthi-
keyan, R. Haridharan, C.-H. Cheng, Angew. Chem.
2012, 124, 12509; Angew. Chem. Int. Ed. 2012, 51,
12343; e) K. Muralirajan, C.-H. Cheng, Chem. Eur. J.
2013, 19, 6198; f) C.-Z. Luo, P. Gandeepan, C.-H.
Cheng, Chem. Commun. 2013, 49, 8528.
[9] The formation of diethyl ketone was demonstrated by
1
means of a crude H NMR experiment.
[10] a) X.-Y. Shi, A. Renzetti, S. Kundu, C.-J. Lia, Adv.
Synth. Catal. 2014, 356, 723; b) J. R. Huckins, E. A.
Bercot, O. R. Thiel, T.-L. Hwang, M. M. Bio, J. Am.
Chem. Soc. 2013, 135, 14492.
[11] a) E. M. Simmons, J. F. Hartwig, Angew. Chem. 2012,
124, 3120; Angew. Chem. Int. Ed. 2012, 51, 3066;
b) N. R. Deprez, M. S. Sanford, J. Am. Chem. Soc.
2009, 131, 11234.
[7] a) M. D. K. Boele, G. P. F. van Strijdonck, A. H. M.
de Vries, P. C. J. Kamer, J. G. de Vries, P. W. N. M. van
Leeuwen, J. Am. Chem. Soc. 2002, 124, 1586; b) F. W.
6
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COMMUNICATIONS
Rhodium(III)-Catalyzed in situ Oxidizing Directing Group-
7
À
Assisted C H Bond Activation and Olefination: A Route
to 2-Vinylanilines
Adv. Synth. Catal. 2015, 357, 1 – 7
Krishnamoorthy Muralirajan, Radhakrishnan Haridharan,
Sekar Prakash, Chien-Hong Cheng*
Adv. Synth. Catal. 0000, 000, 0 – 0
ꢀ 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
7
ÞÞ
These are not the final page numbers!