Ruthenium-catalyzed direct C-H amidation of arenes including weakly coordinating aromatic ketones

Article abstract of DOI:10.1002/chem.201301025

C-H activation: The ruthenium-catalyzed direct sp² C-H amidation of arenes by using sulfonyl azides as the amino source is presented (see scheme). A wide range of substrates were readily amidated including arenes bearing weakly coordinating groups. Synthetic utility of the thus obtained products was demonstrated in the preparation of biologically active heterocycles. Copyright

Full text of DOI:10.1002/chem.201301025

COMMUNICATION
DOI: 10.1002/chem.201301025
À
Ruthenium-Catalyzed Direct C H Amidation of Arenes Including Weakly
Coordinating Aromatic Ketones
Jiyu Kim, Jinwoo Kim, and Sukbok Chang*[a]
À
Highly efficient and selective formation of C N bonds is
one of the most important research topics in organic synthe-
sis mainly due to the fact that numerous amine-containing
molecules are bioactive, finding their utilities in medicinal
and agrochemical chemistry as well as in organic synthesis
and materials chemistry.[1] Although metal-mediated amina-
tion of aryl (pseudo)halides has been well developed as the
oped on the basis of ruthenium(0) or ruthenium(II) sys-
tems.[8] In particular, recent efforts to utilize the unique cat-
alytic activity of [RuACHTUNRGTNEUNG(arene)Cl2]2 complexes have resulted in
À
significant advances in the direct C H bond functionaliza-
tions (Scheme 1a).[9] Despite these achievements, however,
À
the ruthenium-catalyzed C H bond activation strategy has
been practiced almost exclusively for the introduction of
most reliable and practical method for the C N bond for-
alkyl, vinyl, or aryl groups.[6b,8d] In fact, intermolecular direct
À
mation,[2] the requirement of prefunctionalized haloarene re-
actants has led chemists to search for alternative ap-
proaches. As a consequence, an
C H amination of arenes mediated by ruthenium species
À
still remains largely unexplored.[10,11]
extensive study has been devot-
ed to metal-mediated direct
À
C H amination of (hetero)-
A
arenes.[3] While direct reaction
of parent amines with arenes is
most desirable with respect to
atom economy (two hydrogen
atoms are the byproducts), ex-
ternal oxidants are required to
quench the side products under
suitable oxidative conditions.[4]
On the other hand, to avoid the
use of oxidants, preactivated
amino precursors, such as halo-
genated amines, have been ex-
amined as a reagent to react
with arenes.[5] However, there
are two main limitations in this
approach: 1) an additional pro-
À
Scheme 1. Ru-catalyzed direct C H bond functionalizations.
cedure is needed to prepare the haloamine reactants and
2) hydrogen halides are generated as byproducts in amina-
tion reactions and, therefore, external bases are usually em-
ployed to quench these side products.
Along with our continuous efforts on the development of
highly efficient direct amination reactions,[12] we recently re-
2
À
ported a new approach of rhodium-catalyzed direct sp C H
amination by using azides as the amino source, thus releas-
ing molecular nitrogen as a single byproduct.[13] The devel-
oped procedure was successfully applied to the amination of
various arene substrates without requiring external oxidants.
Herein, we describe inexpensive ruthenium-catalyzed direct
Ruthenium complexes have been widely employed as one
À
of the most efficient and selective catalysts for the C H
bond activation.[6] Since the milestone work of Murai,[7]
a
À
large number of C H activation reactions have been devel-
À
C H amidation of arenes by using sulfonyl azides (Sche-
me 1b).[14] Importantly, a new type of substrate that has
weak coordinating ability can now be amidated under the
new ruthenium catalyst system, thereby greatly expanding
the synthetic and practical utility of our approach.
[a] J. Kim, J. Kim, Prof. Dr. S. Chang
Center for Catalytic Hydrocarbon Funtionalizations (IBS)
and Department of Chemistry, Korea Advanced Institute of Science
and Technology (KAIST), Daejeon 305–701 (Korea)
Fax : (+82)42-350-2810
We first explored ruthenium catalyst systems in a reaction
of N-tert-butylbenzamide (1a) with para-toluenesulfonyl
azide (2a) under various conditions (Table 1). Whereas
E-mail: sbchang@kaist.ac.kr
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/chem.201301025.
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Table 1. Optimization studies of the Ru-catalyzed amidation.[a]
amidated into benzamide in equal efficiency with high yields
(3o–r and 3s–t, respectively). It needs to be mentioned that
diamidated compounds were not generated in any detect-
AHCTUNGTREGUNaNN ble amounts by H NMR spectroscopy (<5%) under the
most optimal conditions. On the other hand, aryl azides,
which were successfully utilized in the rhodium-catalyzed
Entry
Additive
Solvent
T [oC]
Yield [%][d]
[13b]
À
direct C H aminidation of arenes,
the present ruthenium catalyst system.
were ineffective under
1
2
3
4
5
6
7
–
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
ClCH2CH2Cl
Toluene
80
80
80
80
80
80
80
80
50
80
80
80
80
n.r.
5
AgPF6
AgBF4
AgOTf
NaPF6
AgSbF6
AgNTf2
AgNTf2
AgNTf2
AgNTf2
AgNTf2
AgNTf2
AgNTf2
Encouraged by the successful results of the direct amida-
tion of benzamides, we next tried to explore a new type of
substrate with weak coordinating ability.[15] In particular,
aryl ketones were selected to be tested since amidated prod-
ucts, 2-aminoaryl ketones, have a variety of synthetic utilit-
ies (vide infra). We were delighted to see that acetophe-
none, indeed, was readily amidated by an in situ generated
cationic ruthenium catalyst with the help of acetate additive
in this case (Table 3).[6b,16] In sharp contrast, our previous
rhodium catalyst system[13] was not operative for this amida-
tion of acetophenone. Although Liu et al. recently reported
the Pd-catalyzed amidation of aryl ketones by using sulfona-
mides, the scope was rather limited to substrates bearing
mainly bulky alkyl moieties to give satisfactory yields.[4 h]
A wide range of aryl ketones were subsequently subjected
to the above optimal conditions (Table 4). As in the case of
aromatic ketones, the amidation took place smoothly re-
gardless of the position and electronic properties of substitu-
23
15
n.r.
40
50
89
11
12
47
70
11
8[b]
9[b]
10[b]
11[b]
12[b]
13[b,c]
tert-amylOH
1,4-dioxane
ClCH2CH2Cl
[a] Conditions: 1a (0.2 mmol), 2a (1.2 equiv), [RuCl2ACTHUNTRGNEU(GN p-cymene)]2
(4 mol%), and additive (16 mol%) in solvent (0.5 mL) for 12 h at the in-
dicated temperature. [b] 1a (2 equiv) and 2a (0.2 mmol) under otherwise
identical conditions for 12 h. [c] [RuACHTUNTRGNEUNG(benzene)Cl2]2 (4 mol%) was used as
the Ru catalyst. [d] Yield was determined by 1H NMR spectroscopy by
using an internal standard.
ruthenium precursors other than [RuCl2ACTHUNTRGNE(NUG p-cymene)]2 or its
analogues were inactive, the nature of additives, which con-
vert the dimeric ruthenium(II) complexes to their
corresponding cationic species, turned out to be
most important.
Table 2. Scope of benzamide substrates.[a]
Among several silver salts screened, AgSbF6 and
AgNTf2 (4 equiv to Ru catalyst) were especially ef-
fective (Table 1, entries 6–7) albeit the latter addi-
tive provided slightly higher efficiency. It was also
found that when an azide was employed as a limit-
ing reactant, product yield was significantly in-
creased (entry 8). While the reaction was best per-
formed at 808C in 1,2-dichloroethane, lower effi-
ciency was the result either at lower temperatures
or in different solvents (entries 9–12). Interestingly,
an analogous ruthenium species [RuACTHNUTRGNE(UNG benzene)Cl2]2
displayed much inferior reactivity (entry 13).
The optimized amidation conditions were next
applied to a range of benzamides in reaction with
sulfonyl azides (Table 2). The position and electron-
ic variation of substituents in benzamides little in-
fluenced the reaction efficiency (3b–f). Importantly,
functional-group tolerance was excellent under the
present conditions as can be demonstrated by sub-
strates bearing bromo, ester, free hydroxyl, and ace-
tate groups (3g, 3h, 3i, and 3j, respectively). N-tert-
Butyl-2-naphthamide was exclusively amidated at
the 3-position in high yield (3k). It was also ob-
served that the N-alkyl substitutents of benzamides
were highly flexible to include adamantyl, cyclohex-
yl, and isopropyl (3l–n) in addition to a tert-butyl
group. Finally, the scope of sulfonyl azides was also
very broad: both arene and alkane variants were [a] Conditions: 1 (2 equiv), 2 (0.2 mmol). Isolated yields are given. [b] Run for 48 h.
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Ruthenium-Catalyzed Direct C H Amidation of Arenes
COMMUNICATION
Table 3. Direct amidation of acetophenone.[a]
of sulfonyl azides were smoothly introduced at the ortho po-
sition of acetophenone in moderate to good yields (5aa–af).
It should be noted that the reaction could be scaled up with-
out difficulty on a gram quantity (see the Supporting Infor-
mation for details).
2
Yield [%][b]
À
Direct sp C H amidation of arenes bearing strong coor-
Additive ([mol%])
dinating nitrogen groups was briefly investigated under the
current ruthenium system (Table 5). We were pleased to ob-
serve that representative directing groups, such as 2-pyridyl,
pyrazol, and ketoxime moieties all facilitated the desired
amidation in the presence of AgSbF6 salt and acetate addi-
tive.
no additive
CsOPiv (20)
KOAc (20)
NaOAc (20)
5
n.r.
60
70
[a] Conditions: 4a (2 equiv) and 2a (0.2 mmol). [b] 1H NMR spectrosco-
py.
Table 4. Scope of aryl ketone substrates.[a]
Table 5. Preliminary scope of substrates bearing heterocyclic directing
groups.[a]
[a] Conditions: 7 (2 equiv) and 2 (0.2 mmol). Isolated yields are given.
It was interesting to note that amidation proceeds with
significantly different initial rates depending on substrates
employed. Quite surprisingly, the reaction of weakly coordi-
nating acetophenone took place much faster than benz-
AHCTUNGTREGaNNUN mides and 2-phenylpyridine, which displayed similar reac-
tivity to each other (Figure 1). Although the exact reason
for this observation is not clear at the present stage, it is as-
À
sumed that the relative ease of the rate-limiting C H activa-
tion step is reflected in this rate difference.
To gain a mechanistic insight into our Ru-catalyzed ami-
dation reaction, a series of preliminary studies were carried
À
out. A deuterium scrambling test revealed that C H bond
[a] Conditions: 4 (2 equiv) and 2 (0.2 mmol). Isolated yields are given.
activation is irreversible (Scheme 2a). A significant degree
of primary kinetic isotopic effects was observed with both
N-tert-butylbenzamide and aceotophenone substrates (Sche-
À
ents on substrates (5a–f). In addition, the conditions were
compatible with the various organic functional groups exam-
ined (e.g. 5g–i). Derivatives of alkyl aryl ketones or benzo-
phenone were readily amidated under the present condi-
tions (5j–o and 5p, respectively). As expected, all variants
me 2b and c), which implied that the C H bond cleavage is
involved in the rate-limiting step.[17] The electronic effects of
substituents on the reaction rate was tested to reveal that
aryl ketones bearing electron-donating groups displayed
faster initial rates than electron-deficient substrates. For ex-
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S. Chang et al.
Based on the above mecha-
nistic data and precedent re-
ports,[13,16b,18] a plausible mecha-
nistic pathway is depicted in
Scheme 3 with acetophenone as
a model substrate.[19] Silver salt
is believed to convert the neu-
tral ruthenium precursor to its
cationic species.[16b] As implied
by the above described elec-
tronic effects on the initial
À
rates, the C H bond activation
Figure 1. Reaction profile of amidation among three different types of substrates under the present Ru-catalyst
system.
is postulated to proceed by an
electrophilic aromatic metala-
tion pathway leading to the
ruthenacycle species I.[20] A re-
versible coordination of azide
to the cationic metal center will
be followed by an amido inser-
tion to release a nitrogen mole-
cule giving rise to III, which is
eventually protonated to afford
the desired amidated product.
As a synthetic application,
acetophenone bearing a boro-
nate substituent (4q) was ami-
dated under the present Ru-cat-
alyzed conditions to afford 5q,
which was in situ coupled with
4-iodoacetophenone by
a Pd
catalyst system to provide 9 in
satisfactory yield [Eq. (1)].
It is also noteworthy that syn-
thetic utility of ortho-amido
aryl ketone products is signifi-
cant, and a wide range of bioac-
tive heterocycles could be syn-
thesized by simple conventional
methods (Scheme 4).[21] In fact,
synthetic procedures are known
for the preparation of oxcarba-
zepines, indazoles, (oxy)indoles,
and quinoline derivatives by
Scheme 2. Preliminary mechanistic studies.
ample, 4-methoxyacetophenone
was amidated about four-times
faster
than
acetophenone,
which was in turn faster than 4-
chloroacetophenone by about
two times (see the Supporting
Information for details).
A
ruthenacycle species A was iso-
lated and characterized by X-
ray crystallographic analysis
(Scheme 2d). When A was treated with sulfonyl azide under
the reaction conditions, the corresponding amido insertion
metal species B was detected by mass spectroscopy.
starting from a common precursor, ortho-amido aryl ke-
tones, and some examples are demonstrated herein.
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Ruthenium-Catalyzed Direct C H Amidation of Arenes
COMMUNICATION
Experimental Section
Representative procedure: Acetophenone (4a, 0.4 mmol), p-toluenesul-
fonyl azide (2a, 0.2 mmol), [RuCl2ACHTNUGTRENUNG(p-cymene)]2 (4.9 mg, 4 mol%),
AgNTf2 (12.5 mg, 16 mol%), NaOAc (3.3 mg, 20 mol%), and 1,2-di-
chloroethane (0.5 mL) were added to a screw-capped vial equipped with
a spinvane triangular-shaped Teflon stirbar. The reaction mixture was
stirred in a preheated oil bath at 808C for 12 h and then cooled to room
temperature, filtered through a pad of Celite, and washed with ethyl ace-
tate (10 mLꢁ3). The filtrate was concentrated under reduced pressure
and the residue was purified by chromatography on silica gel (n-hexane/
EtOAc 3:1) to give the desired product 5a (56.1 mg, 97%).
Acknowledgements
This research was supported by the Institute of Basic Science (IBS).
Scheme 3. Proposed reaction pathway.
Keywords: amination
·
·
À
catalysis
·
C H activation
ruthenium · sulfonyl azides
[1] a) R. Hili, A. K. Yudin, Nat.
Chem. Biol. 2006, 2, 284;
b) Amino Group Chemistry, From
Synthesis to the Life Sciences
(Ed.: A. Ricci),Wiley-VCH, Wein-
heim, 2007.
[2] a) M. Kosugi, M. Kameyama, T.
Migita, Chem. Lett. 1983, 12, 927;
b) F. Paul, J. Patt, J. F. Hartwig, J.
Am. Chem. Soc. 1994, 116, 5969;
c) A. S. Guram, S. L. Buchwald, J.
Am. Chem. Soc. 1994, 116, 7901;
d) G. Evano, N. Blanchard, M.
Toumi, Chem. Rev. 2008, 108,
3054.
[3] a) A. Armstrong, J. C. Collins,
Angew. Chem. 2010, 122, 2332;
Angew. Chem. Int. Ed. 2010, 49,
2282; b) S. H. Cho, J. Y. Kim, J.
Kwak, S. Chang, Chem. Soc. Rev.
2011, 40, 5068; c) J. Wencel-
Delord, T. Drçge, F. Liu, F. Glo-
rius, Chem. Soc. Rev. 2011, 40,
4740; and for amination reactions
Scheme 4. Synthetic utility of amidated products.
In summary, we have presented the inexpensive rutheni-
2
À
um-catalyzed direct sp C H amidation of arenes by using
À
with C H activation, see: d) W. C. P. Tsang, N. Zheng, S. L. Buch-
wald, J. Am. Chem. Soc. 2005, 127, 14560; e) J. A. Jordan-Hore,
C. C. C. Johansson, M. Gulias, E. M. Beck, M. J. Gaunt, J. Am.
Chem. Soc. 2008, 130, 16184; for amination reactions with nitrene
precursors, see: f) C. G. Espino, P. M. Wehn, J. Chow, J. Du Bois, J.
Am. Chem. Soc. 2001, 123, 6935; g) K. W. Fiori, J. Du Bois, J. Am.
Chem. Soc. 2007, 129, 562.
sulfonyl azides as the nitrogen source. While a wide range of
substrates were readily amidated, compounds bearing weak
coordinating groups were also reacted with excellent effi-
ciency and selectivity. Indeed, the introduction of an amido
unit at the ortho-position of aryl ketones was unprecedent-
edly facile, which cannot be achieved with other catalytic
systems, such as rhodium or palladium. Synthetic utility of
the thus obtained products is enormous serving as a
common synthetic building unit for the preparation of a
wide range of biologically active heterocycles.
[4] For oxidative amination of activated arenes, see: a) Q. Wang, S. L.
Schreiber, Org. Lett. 2009, 11, 5178; b) D. Monguchi, T. Fujiwara, H.
Furukawa, A. Mori, Org. Lett. 2009, 11, 1607; c) S. H. Cho, J. Y.
Kim, S. Y. Lee, S. Chang, Angew. Chem. 2009, 121, 9291; Angew.
Chem. Int. Ed. 2009, 48, 9127; d) Y. Oda, K. Hirano, T. Satoh, M.
Miura, Org. Lett. 2012, 14, 664; for oxidative amination of arenes
bearing directing groups, see: e) T. Uemura, S. Imoto, N. Chatani,
Chem. Lett. 2006, 35, 842; f) X. Chen, X.-S. Hao, C. E. Goodhue, J.-
Q. Yu, J. Am. Chem. Soc. 2006, 128, 6790; g) H.-Y. Thu, W.-Y. Yu,
C.-M. Che, J. Am. Chem. Soc. 2006, 128, 9048; h) B. Xiao, T.-J.
Gong, J. Xu, Z.-J. Liu, L. Liu, J. Am. Chem. Soc. 2011, 133, 1466;
Chem. Eur. J. 2013, 00, 0 – 0
ꢀ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
&
5
&
ÞÞ
These are not the final page numbers!

S. Chang et al.
i) A. John, K. M. Nicholas, J. Org. Chem. 2011, 76, 4158; j) B. Haffe-
mayer, M. Gulias, M. J. Gaunt, Chem. Sci. 2011, 2, 312.
1304; c) S. Cenini, E. Gallo, A. Caselli, F. Ragaini, S. Fantauzzi, C.
Piangiolino, Coord. Chem. Rev. 2006, 250, 1234; d) B. J. Stokes, H.
Dong, B. E. Leslie, A. L. Pumphrey, T. G. Driver, J. Am. Chem. Soc.
2007, 129, 7500; e) J. V. Ruppel, R. M. Kamble, X. P. Zhang, Org.
Lett. 2007, 9, 4889; f) Y. M. Badiei, A. Dinescu, X. Dai, R. M. Palo-
mino, F. W. Heinemann, T. R. Cundari, T. H. Warren, Angew. Chem.
2008, 120, 10109; Angew. Chem. Int. Ed. 2008, 47, 9961; g) Y.-F.
Wang, K. K. Toh, J.-Y. Lee, S. Chiba, Angew. Chem. 2011, 123, 6049;
Angew. Chem. Int. Ed. 2011, 50, 5927; h) A. R. Fout, Q. Zhao, D. J.
Xiao, T. A. Betley, J. Am. Chem. Soc. 2011, 133, 16750; i) S. Chiba,
Synlett 2012, 23, 21; j) G. Dequirez, V. Pons, P. Dauban, Angew.
Chem. 2012, 124, 7498; Angew. Chem. Int. Ed. 2012, 51, 7384; k) Y.
Fukunaga, T. Uchida, Y. Ito, K. Matsumoto, T. Katsuki, Org. Lett.
2012, 14, 4658; l) Q. Nguyen, T. Nguyen, T. G. Driver, J. Am. Chem.
Soc. 2013, 135, 620; m) Y. Nishioka, T. Uchida, T. Katsuki, Angew.
Chem. 2013, 125, 1783; Angew. Chem. Int. Ed. 2013, 52, 1739.
[5] a) T. Kawano, K. Hirano, T. Satoh, M. Miura, J. Am. Chem. Soc.
2010, 132, 6900; b) K.-H. Ng, A. S. C. Chan, W.-Y. Yu, J. Am. Chem.
Soc. 2010, 132, 12862; c) K. Sun, Y. Li, T. Xiong, J. Zhang, Q.
Zhang, J. Am. Chem. Soc. 2011, 133, 1694; d) E. J. Yoo, S. Ma, T.-S.
Mei, K. S. L. Chan, J.-Q. Yu, J. Am. Chem. Soc. 2011, 133, 7652;
e) K.-H. Ng, Z. Zhou, W.-Y. Yu, Org. Lett. 2012, 14, 272; f) C. Groh-
mann, H. Wang, F. Glorius, Org. Lett. 2012, 14, 656; g) Y. Miki, K.
Hirano, T. Satoh, M. Miura, Org. Lett. 2013, 15, 172.
[6] a) L. Ackermann, R. Vicente, Top. Curr. Chem. 2009, 292, 211;
b) P. B. Arockiam, C. Bruneau, P. H. Dixneuf, Chem. Rev. 2012, 112,
5879.
[7] S. Murai, F. Kakiuchi, S. Sekine, T. Danaka, A. Kamatani, M.
Sonoda, N. Chatani, Nature 1993, 366, 529.
À
[8] For ruthenium(0)-catalyzed C H bond functionalizations, see: a) F.
À
Kakiuchi, S. Murai, Acc. Chem. Res. 2002, 35, 826; b) F. Kakiuchi,
N. Chatani, Adv. Synth. Catal. 2003, 345, 1077; for ruthenium(II)-
[15] For direct C H funtionalizations assisted by weak coordinating
groups, see: K. M. Engle, T.-S. Mei, M. Wasa, J.-Q. Yu, Acc. Chem.
À
catalyzed C H bond functionalizations, see: c) I. ꢂzdemir, S.
Res. 2012, 45, 788.
À
Demir, B. C¸ etinkaya, C. Gourlaouen, F. Maseras, C. Bruneau, P. H.
Dixneuf, J. Am. Chem. Soc. 2008, 130, 1156; d) L. Ackermann,
Chem. Rev. 2011, 111, 1315.
[16] For carboxylate effects in the Ru-catalyzed C H bond functionaliza-
tions, see: a) P. B. Arockiam, C. Fischmeister, C. Bruneau, P. H. Dix-
neuf, Angew. Chem. 2010, 122, 6779; Angew. Chem. Int. Ed. 2010,
49, 6629; b) K. Padala, M. Jeganmohan, Org. Lett. 2011, 13, 6144;
c) Y. Hashimoto, T. Ortloff, K. Hirano, T. Satoh, C. Bolm, M.
Miura, Chem. Lett. 2012, 41, 151; d) B. Li, J. Ma, N. Wang, H. Feng,
S. Xu, B. Wang, Org. Lett. 2012, 14, 736; e) V. S. Thirunavukkarasu,
M. Donati, L. Ackermann, Org. Lett. 2012, 14, 3416; f) V. K.-Y. Lo,
Z. Guo, M. K.-W. Choi, W.-Y. Yu, J.-S. Huang, C.-M. Che, J. Am.
Chem. Soc. 2012, 134, 7588; g) L. Ackermann, J. Pospech, K. Grac-
zyk, K. Rauch, Org. Lett. 2012, 14, 930.
[9] a) S. Oi, S. Fukita, N. Hirata, N. Watanuki, S. Miyano, Y. Inoue,
Org. Lett. 2001, 3, 2579; b) S. Oi, Y. Ogino, S. Fukita, Y. Inoue, Org.
Lett. 2002, 4, 1783; c) L. Ackermann, Org. Lett. 2005, 7, 3123; d) F.
ˇ
Pozgan, P. H. Dixneuf, Adv. Synth. Catal. 2009, 351, 1737; e) L. Ac-
kermann, R. Vicente, A. R. Kapdi, Angew. Chem. 2009, 121, 9976;
Angew. Chem. Int. Ed. 2009, 48, 9792; f) L. Ackermann, A. V. Lygin,
N. Hofmann, Angew. Chem. 2011, 123, 6503; Angew. Chem. Int. Ed.
2011, 50, 6379.
[10] During the preparation of this manuscript, the Ru-catalyzed ortho-
amidation of N-benzoylated sulfoximines was reported by using sul-
fonyl azides as the amino source: M. R. Yadav, R. K. Rit, A. K.
Sahoo, Org. Lett. 2013, 15, 1638.
[17] E. M. Simmons, J. F. Hartwig, Angew. Chem. 2012, 124, 3120;
Angew. Chem. Int. Ed. 2012, 51, 3066.
[18] a) G. Guillemot, E. Solari, C. Floriani, C. Rizzoli, Organometallics
2001, 20, 607; b) A. R. Dick, M. S. Remy, J. W. Kampf, M. S. San-
ford, Organometallics 2007, 26, 1365; c) B. C. Boren, S. Narayan,
L. K. Rasmussen, L. Zhang, H. Zhao, Z. Lin, G. Jia, V. V. Fokin, J.
Am. Chem. Soc. 2008, 130, 8923; d) H. Wu, M. B. Hall, J. Am.
Chem. Soc. 2008, 130, 16452; e) W. G. Shou, J. Li, T. Guo, Z. Lin, G.
Jia, Organometallics 2009, 28, 6847.
À
[11] For Ru-catalyzed intramolecular C N bond formation, see: a) J.-L.
Liang, S.-X. Yuan, J.-S. Huang, W.-Y. Yu, C.-M. Che, Angew. Chem.
2002, 114, 3615; Angew. Chem. Int. Ed. 2002, 41, 3465; b) J.-L.
Liang, S.-X. Yuan, J.-S. Huang, C.-M. Che, J. Org. Chem. 2004, 69,
3610; c) E. Milczek, N. Boudet, S. Blakey, Angew. Chem. 2008, 120,
6931; Angew. Chem. Int. Ed. 2008, 47, 6825; d) J. Hu, S. Chen, Y.
Sun, J. Yang, Y. Rao, Org. Lett. 2012, 14, 5030; for Ru-catalyzed in-
[19] An inspiring study on the mechanistic aspect of a similar RuII cata-
lyst system was recently reported: E. F. Flegeau, C. Bruneau, P. H.
Dixneuf, A. Jutand, J. Am. Chem. Soc. 2011, 133, 10161.
À
termolecular C N bond formation, see: e) X.-Q. Yu, J.-S. Huang,
À
X.-G. Zhou, C.-M. Che, Org. Lett. 2000, 2, 2233; f) J.-L. Liang, J.-S.
Huang, X.-Q. Yu, N. Zhu, C.-M. Che, Chem. Eur. J. 2002, 8, 1563.
[12] a) J. Y. Kim, S. H. Cho, J. Joseph, S. Chang, Angew. Chem. 2010,
122, 10095; Angew. Chem. Int. Ed. 2010, 49, 9899; b) S. H. Cho, J.
Yoon, S. Chang, J. Am. Chem. Soc. 2011, 133, 5996; c) H. J. Kim, J.
Kim, S. H. Cho, S. Chang, J. Am. Chem. Soc. 2011, 133, 16382.
[13] a) J. Y. Kim, S. H. Park, J. Ryu, S. H. Cho, S. H. Kim, S. Chang, J.
Am. Chem. Soc. 2012, 134, 9110; b) J. Ryu, K. Shin, S. H. Park, J. Y.
Kim, S. Chang, Angew. Chem. 2012, 124, 10042; Angew. Chem. Int.
Ed. 2012, 51, 9904.
[20] For the C H funtionalization involving an electrophilic metalation,
see : a) X. Wang, B. S. Lane, D. Sames, J. Am. Chem. Soc. 2005, 127,
4996; b) M. Tobisu, Y. Ano, N. Chatani, Org. Lett. 2009, 11, 3250.
[21] a) C. Theeraladanon, M. Arisawa, A. Nishida, M. Nakagawa, Tetra-
hedron 2004, 60, 3017; b) M. Carril, R. SanMartin, F. Churruca, I.
Tellitu, E. Domꢄnguez, Org. Lett. 2005, 7, 4787; c) Y. Hari, T. Kanie,
T. Miyagi, T. Aoyama, Synthesis 2006, 1249; d) C. M. Counceller,
C. C. Eichman, B. C. Wray, J. P. Stambuli, Org. Lett. 2008, 10, 1021;
e) Y. Sun, R. Fan, Chem. Commun. 2010, 46, 6834; f) F. Pan, Z.-Q.
Lei, H. Wang, H. Li, J. Sun, Z.-J. Shi, Angew. Chem. 2013, 125, 2117;
Angew. Chem. Int. Ed. 2013, 52, 2063.
[14] For recent examples on the use of azides as the nitrogen source in
the metal-mediated amination reactions, see: a) S. Brꢃse, C. Gil, K.
Knepper, V. Zimmermann, Angew. Chem. 2005, 117, 5320; Angew.
Chem. Int. Ed. 2005, 44, 5188; b) T. Katsuki, Chem. Lett. 2005, 34,
Received: March 18, 2013
Published online: && &&, 0000
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ꢀ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 0000, 00, 0 – 0
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These are not the final page numbers!

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Ruthenium-Catalyzed Direct C H Amidation of Arenes
COMMUNICATION
Synthetic Methods
J. Kim, J. Kim, S. Chang* . . &&&& — &&&&
À
Ruthenium-Catalyzed Direct C H
Amidation of Arenes Including
Weakly Coordinating Aromatic
Ketones
À
C H activation: The ruthenium-cata-
bearing weakly coordinating groups.
2
À
lyzed direct sp C H amidation of
Synthetic utility of the thus obtained
products was demonstrated in the
preparation of biologically active het-
erocycles.
arenes by using sulfonyl azides as the
amino source is presented (see
scheme). A wide range of substrates
were readily amidated including arenes
Chem. Eur. J. 2013, 00, 0 – 0
ꢀ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemeurj.org
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These are not the final page numbers!