Palladium(0)-catalyzed carbon-Hydrogen bond functionalization for the synthesis of indoloquinazolinones

Article abstract of DOI:10.1002/adsc.201400078

The indoloquinazolinone ring system has attracted considerable attention as a pharmacophore, because it shows various biological activities. The reported synthetic methods for the compound are simple and direct, but are not effective for the direct synthesis of indoloquinazolinone with a methylene group at the C-6 position. A palladium(0)-catalyzed cyclization of chloroquinazolinone via C-H functionalization was developed for a concise synthesis of indoloquinazolinone derivatives. The presence of a substituent at the C-6 position is important for obtaining the product in good yield. The conformation of the reaction intermediate, in particular the N-C-Pd bond angle, is important for the regioselectivity of the reaction.

Full text of DOI:10.1002/adsc.201400078

COMMUNICATIONS
DOI: 10.1002/adsc.201400078
À
Palladium(0)-Catalyzed Carbon Hydrogen Bond
Functionalization for the Synthesis of Indoloquinazolinones
Chihiro Tsukano,a Masataka Okuno,a Hiromi Nishiguchi,a and Yoshiji Takemotoa,*
a
Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
Fax : (+81)-(0)75-753-4532; e-mail: Takemoto@pharm.kyoto-u.ac.jp
Received: January 21, 2014; Revised: March 9, 2014; Published online: April 30, 2014
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201400078.
Abstract: The indoloquinazolinone ring system has
attracted considerable attention as a pharmaco-
phore, because it shows various biological activities.
The reported synthetic methods for the compound
are simple and direct, but are not effective for the
direct synthesis of indoloquinazolinone with a meth-
ylene group at the C-6 position. A palladium(0)-cat-
sis of phaitanthrins.[7] Reactions that generate indolo-
quinazolinone under mild conditions using Oxone-in-
duced[8] and copper-catalyzed aerobic oxidation[9]
were developed by Grundt, and Liu and Wang, re-
spectively. These synthetic methods are simple and
direct, but are not effective for the direct synthesis of
indoloquinazolinone with a methylene group at the
C-6 position. For accessing the indoloquinazolinone,
a two-step sequence consisting of a formation of indo-
loquinazolinedione and a reduction is often em-
ployed.[10] While there are three reports of direct con-
struction of the reduced form, the scope of these
methods is limited.[11] There remains a need for
a direct method to construct the reduced form.
À
alyzed cyclization of chloroquinazolinone via C H
functionalization was developed for a concise syn-
thesis of indoloquinazolinone derivatives. The pres-
ence of a substituent at the C-6 position is impor-
tant for obtaining the product in good yield. The
conformation of the reaction intermediate, in par-
À À
ticular the N C Pd bond angle, is important for
3
À
the regioselectivity of the reaction.
Pd-catalyzed C
N
ed attention for the development of more straightfor-
Keywords: C H functionalization; cyclization; in-
ward synthetic routes with better atom economy.[12]
À
3
À
doloquinazolinone; palladium; regioselectivity; sub-
stituent effects
To date, several examples of Pd-catalyzed C
N
functionalization for the synthesis of heterocycles
have been reported, including indole-related com-
pounds.[13–15] We previously reported the synthesis of
oxindole and spirooxindole from carbamoyl chlorides
with a methyl and cyclopropyl group at the ortho-po-
3
À
Indoloquinazolinone has a tetracyclic alkaloid skele- sition, through oxidative addition, benzylic C
ton consisting of a quinazolinone fused to an indole
unit and is found in several natural products including
tryptanthrin,[1a,b] phaitanthrins[1c] and ophiuroidine[1d]
(Figure 1). These alkaloids show various biological ac-
tivities, including antibiotic,[2] antiparasitic,[3] antican-
cer,[1c,4] and antitubercular[5] activities. As such, the in-
doloquinazolinone system has attracted considerable
attentions as a pharmacophore.
(sp ) H
To date, several synthetic methods have been devel-
oped to further the biological studies on these natural
products and their congeners.[1b] Indoloquinazolinones
are generally prepared by the coupling of isatin and
isatoic anhydride, under basic conditions, although
the scope of this method is limited.[6] Recently,
Argade and co-workers reported an aryne insertion
into quinazolinones as an effective synthesis for indo-
loquinazolinone, and achieved a concise total synthe- Figure 1. Indoloquinazolinone-containing natural products.
Adv. Synth. Catal. 2014, 356, 1533 – 1538
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1533

COMMUNICATIONS
Chihiro Tsukano et al.
no reaction (entries 3–6). Interestingly, the reaction
with 20 mol% PPh3 proceeded to give 2a, although at
10 mol% of ligand, the yield significantly decreased
(entries 7 and 8). To improve the yields, several palla-
dium catalysts were also examined. While [h3-
(C3H5)PdCl]2 was not effective, it was found that Pd2
A
ACHTUNGTRENN(NUG PPh3)4 gave better
AHCTUNGTRENNUNG
ing of bases, additives, temperature and solvents was
performed. Several bases were tested including
K2CO3, Cs2CO3 and NaOAc, which gave the product
2a in 26–42% yield (entries 12–14). No desired prod-
uct was obtained in the case of triethylamine
(entry 15). The use of an additive was essential for
this reaction, and PivNHOH gave a higher yield than
PivOH (entries 16 and 17).[15a] While higher reaction
temperatures gave lower yields, at 100–1208C the re-
action proceeded to give a reasonable yield (en-
tries 18 and 19). Aromatic hydrocarbons including
3
À
Scheme 1. Pd(0)-catalyzed CACTHNUTRGENUGN(sp ) H functionalization for
the synthesis of heterocycles.
activation and reductive elimination of the resultant mesitylene, toluene and PhCl were effective solvents,
palladacycle (Scheme 1).[15a,c] The synthesis of 3-acyl- with the best yields for PhCl (entries 19–21). In con-
2-arylindole derivatives was also performed through trast, the use of dimethylacetamide (entry 22) did not
Pd(0)-catalyzed isocyanide insertion and oxypallada- give any of the cyclized products. Therefore, we set
tion of an alkyne.[15b] These results suggest that indo- the conditions as 5 mol% of Pd
ACHTNUGTRNEUNG(PPh3)4, two equiva-
loquinazolinone could be accessed from chloroquina- lents of Na2CO3 and 30 mol% of PivNHOH in PhCl
3
À
zolinone via Pd(0)-catalyzed C
G
tion. In the synthesis of oxindole, the main side reac-
tion was decarboxylation after oxidative addition, re- the reaction (Table 2). Cyclization of chloroquinazol-
quiring the reaction to be performed under a CO inones 1b–d, containing ethyl, chloro and methoxy
AHCTUNGTRENNUNG
atmosphere. In contrast, CO is not required in the groups, under the optimized conditions proceeded
synthesis of indoloquinazolinone because the reaction smoothly to give indoloquinazolinones 2b–d in good
intermediate is stabilized by attachment to another to excellent yield (entries 1–3). The presence of sub-
ring system. Additionally, this may allow the direct stituents at the other ortho position (i.e., the C-6 posi-
synthesis of indoloquinazolinones having a methylene tion) gave good results, while yields for substrates
group at the C-6 position from simple starting materi- having no substituent at the C-6 position were less fa-
3
À
als. Thus, use of a Pd(0)-catalyzed C
G
tion has good potential for this cyclization. In this quinazolinones 2e–g in yields of 16–58% with a signifi-
paper, we report a short synthesis of the indoloquina- cant amount of starting material recovered (entries 4–
zolinone system in its reduced form, via Pd(0)-cata- 6). This may be attributed to the ortho effect pro-
3
À
lyzed C
G
For initial investigations, chloroquinazolinone 1a cluding fluoro, chloro, methoxy, phenyl, vinyl groups,
was first prepared from 2,6-dimethylaniline in four ester and amine on the aromatic ring were tolerated
steps including isocyanate formation, condensation under these conditions and the desired indoloquinazo-
with anthranilic acid and chlorination using POCl3. linones 2h, i, k–o, s were obtained in moderate to
We first attempted the cyclization of chloroquinazol- good yields (entries 7, 8, 10–14, 18). Interestingly,
ACHTUNGTRENNUNGinone 1a under the conditions used for the synthesis chloroquinazolinones 1c and 1i featuring a chloro sub-
of oxindoles without a CO atmosphere, namely stituent on the aromatic ring could be used for this re-
5 mol% palladium acetate, 10 mol% Ad2PBu, two action and elimination of chloride was not observed
equivalents of Cs2CO3 and 30 mol% N-hydroxypival- (entries 2 and 8). In the case of a substrate having
ACHTUNGTRENNUNGamide (PivNHOH) in mesitylene at 1408C. The reac- a bromo substituent, the cyclization did not proceed
tion proceeded to give indoloquinazolinone 2a in probably due to deactivation of the palladium catalyst
22% yield (Table 1, entry 1). Use of Na2CO3 instead by competitive oxidative addition (entry 9). Although
of Cs2CO3 improved the yield (entry 2). While the re- substrates 1p and 1q having alcohol and carboxylic
action with (t-Bu)3P·HBF4 gave the product 2a in acid were not suitable for this reaction, the reaction
17% yield, the addition of dialkyl
ACHTUNGERTN(NUNG biaryl)phosphine li- of 1r, in which a hydroxy group was protected as
gands including Sphos, Xantphos and DavePhos gave siloxy ether, gave the cyclized product 2r (entries 15–
1534
asc.wiley-vch.de
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2014, 356, 1533 – 1538

À
COMMUNICATIONS
Palladium(0)-Catalyzed Carbon Hydrogen Bond Functionalization
3
À
Table 1. Investigation of Pd(0)-catalyzed C
N
Entry
Pd catalyst
Pd(OAc)2
Ligand
Base
Additive
Solvent
Temperature
Yield [%][a]
1
2
3
4
5
6
7
8
G
Ad2PBu
Ad2PBu
ACHTUNGRTNEN(UNG t-Bu)3P·HBF4
Cs2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Cs2CO3
K2CO3
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
none
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
mesitylene
toluene
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1408C
1608C
1208C
1008C
1208C
1208C
22
56
17
0
0
0
trace
28
28
68
68
26
33
42
0
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
[(h3-C3H5)PdCl]2
ACHTUNGTRENNUNG
R
N
E
T
G
ACHTUNGTRENNUNG
SPhos
Xantphos
DavePhos
PPh3[b]
PPh3
Ad2PBu
Cy3P·HBF4
none
none
none
none
none
none
none
none
none
none
none
none
9
A
[c]
10
11
12
13
14
15
16
17
18
19
20
21
22
Pd
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
Pd(PPh3)4
E
NaOAc
Et3N
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
0
PivOH
34
18
58
46
76
0
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PivNHOH
PhCl
DMA
[a]
Isolated yield.
20 mol% of PPh3 was used.
2.5 mol% of Pd2A(dba)3 was used.
[b]
[c]
CHTUNGTRENNUNG
17). As described in previous reports,[10] the majority
We then turned our attention to the regioselectivity
of the obtained indoloquinazolinones were unstable of the reaction of chloroquinazolinones having sub-
and readily oxidized to indoloquinazolinediones on stituents other than a methyl group. Because we de-
exposure to atmosphere.
veloped the cyclization of compound 10 for the syn-
3
À
Thus we examined a one-pot reaction including cyc- thesis of spirooxindole based on methine C
lization and oxidation for the synthesis of indoloquin- functionalization (Figure 2), the reaction of chloro-
(sp ) H
A
ACHUTGTNRNEUGqN uinACHTUNGTERNaNUGN zolinone 4 having a cyclopropyl group was at-
treated under the same conditions. The argon atmos- tempted under the optimized conditions (Scheme 2).
phere was then replaced by oxygen and the reaction Interestingly, the reaction proceeded to give cyclized
3
À
mixture was stirred at room temperature for several compound 6 in 39% yield via methylene C
G
hours. As expected, indoloquinazolinedione 3a was functionalization, and the indoloquinazolinone 5 was
obtained in 57% yield (entry 1). Several substituents not observed. Additionally, the reaction of 7 with
on the aromatic ring including fluoro, chloro and a benzyl instead of a methyl group resulted in forma-
2
À
alkyl groups were tolerated under these conditions tion of a seven-membered ring via C
(sp ) H function-
for the synthesis of indoloquinazolindiones, although alization, without any five-membered ring formation
the yields were low compared with the corresponding leading to indoloquinazolinone 8. For the carbamoyl
indoloquinazolinones (entry 2–5). Interestingly, oxida- chloride 11, the cyclization did not occur at all. This
tion of the indoloquinazolinone 2o possessing an elec- selectivity was unexpected,[17] and stable conforma-
tron-rich aromatic ring was slow, and the reaction for tions of the chloroquinazolinones 4, 7 and carbamoyl
1 h gave 3o in 24% yield with a significant amount of chlorides 10, 11 were evaluated using Gaussian 09[18]
2o (entry 6).
at the B3LYP/6-31G* level,[19] to explain this result
(Figure 2).[20] Our preliminary calculations indicate
Adv. Synth. Catal. 2014, 356, 1533 – 1538
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
1535

COMMUNICATIONS
Chihiro Tsukano et al.
Table 2. Synthesis of various indoloquinazolinones 2.
Figure 2. Carbamoyl chlorides having cyclopropyl and
benzyl groups and bond angles of the carbamoyl chloride
10, 11 and chloroquinazolinone 4, 7 calculated by Gaussian
09.
Entry R1
R2
Product Yield [%][a]
1
6-Et
H
H
H
H
H
H
2b
2c
2d
2e
2f
2g
2h
2i
quant.
68
70
2
6-Cl
3
4
6-MeO
H
58
5[b]
6[d]
7
3-Me
4-MeO
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me
6-Me, 4-NMe2
32[c]
16[e]
quant.
93%
0%
5’-F
5’-Cl
5’-Br
3’-Me
5’-Ph
5’-CH=CH2 2m
4’-CO2Me 2n
4’,5’-(MeO)2 2o
4’-CO2H
5’-OH
5’-OTBS
H
8
9
2j
10[f]
11
12
13
14
15
16
17
18
2k
2l
63%
74%
52%
80%
99%
0%
2p
2q
2r
2s
0%
43%[g]
90%
[a]
Isolated yield.
The reaction was performed for 6.5 h.
Starting material 1f was recovered in 58% yield.
The reaction was performed for 5.5 h.
Starting material 1g was recovered in 68% yield.
[b]
[c]
[d]
[e]
[f]
10 mol% of PdACHTUNGTRENNUNG
[g]
Table 3. Synthesis of various indoloquinazolinediones 3.
Scheme 2. Regioselective cyclization of chloroquinazol-
AHCTUNGTREGUNiNN nones 4 and 7.
À À
a large difference in the N C Cl bond angles of the
intermediates (115.868 vs. 113.198, for 4 and 10;
116.298 vs. 113.108, for 7 and 11, respectively). It is
suggested that the palladium center of the reaction in-
termediates derived from carbamoyl chlorides 10 and
À
11 is closer to the benzylic C H bond than the cyclo-
Entry
R1
R2
Product
Yield[a]
3
2
À
À
propyl methylene C
(sp ) H and the aromatic C
E
3
À
H bonds. In sharp contrast, the methylene C
of the cyclopropyl ring and the aromatic CACTHGUNTRNE(NUG sp ) H
bonds of the chloroquinazolinones 4 and 7 can readily
approach the palladium center of the intermediate to
form six- and seven-membered rings.
ACHTUNGTNRE(NUNG sp ) H
1
2
3
4
5
6
6-Me
6-Et
6-Cl
6-Me
6-Me
6-Me
H
H
H
5’-F
5’-Cl
4’,5’-(MeO)2
3a
3b
3c
3h
3i
57%
80%
35%
50%
55%
24%[b]
2
À
3o
In summary, we have developed a reaction for the
synthesis of indoloquinazolinone 2 and indoloquin-
À
[a]
Isolated yield.
Compound 2o was also obtained in 70% yield.
[b]
ACHTUNGTRENaNGNU zolinedione 3 via Pd(0)-catalyzed C H functionaliza-
1536
asc.wiley-vch.de
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2014, 356, 1533 – 1538

À
COMMUNICATIONS
Palladium(0)-Catalyzed Carbon Hydrogen Bond Functionalization
Babu, R. C. Puranik, D. Subramanyam, A. Venkates-
warlu, S. Rajagopal, K. B. S. Kumar, C. S. Rao,
N. V. S. R. Mamidi, D. S. Deevi, R. Ajaykumar, R. Ra-
jagopalan, Bioorg. Med. Chem. Lett. 2002, 12, 2303.
[5] J.-M. Hwang, T. Oh, T. Kaneko, A. M. Upton, S. G.
Franzblau, Z. Ma, S.-N. Cho, P. Kim, J. Nat. Prod. 2013,
76, 354.
[6] J. J. Mason, T. Janosik, J. Bergman, Synthesis 2009,
3642.
[7] S. D. Vaidya, N. P. Argade, Org. Lett. 2013, 15, 4006.
[8] A. C. Nelson, E. S. Kalinowski, T. L. Jacobson, P.
Grundt, Tetrahedron Lett. 2013, 54, 6804.
tion. Several substituents were tolerated under the
optimized conditions, although the presence of sub-
stituents at the C-6 position is important for obtaining
the product in good yield. It was found that for sub-
strates containing benzyl and cyclopropyl groups, the
reaction did not occur at the benzylic position proba-
bly because of the larger N C Pd angle of the reac-
tion intermediate compared with that of the carbamo-
yl chloride substrate.
À À
[9] C. Wang, L. Zhang, A. Ren, P. Lu, Y. Wang, Org. Lett.
Experimental Section
2013, 15, 2982.
[10] J. Bergman, U. Tilstam, K.-W. Tçrnroos, J. Chem. Soc.
Perkin Trans. 1 1987, 519.
Synthesis of 10-MethylindoloACHTUNTRGNEUNG[2,1-b]quinazolin-
12(6H)-one (2a)
[11] a) E. S. Lee, J.-G. Park, Y. Jahng, Tetrahedron Lett.
2003, 44, 1883; b) B. Staskun, J. F. Wolfe, S. Afr. J.
Chem. 1992, 45, 5; c) Z. Xia, K. Wang, J. Zheng, Z.
Ma, Z. Jiang, X. Wang, X. Lv, Org. Biomol. Chem.
2012, 10, 1602.
[12] Recent reviews, see: a) X. Chen, K. M. Engle, D.-H.
Wang, J.-Q. Yu, Angew. Chem. 2009, 121, 5196; Angew.
Chem. Int. Ed. 2009, 48, 5094; b) R. Jazzar, J. Hitce, A.
Renaudat, J. Sofack-Kreutzer, O. Baudoin, Chem. Eur.
J. 2010, 16, 2654; c) T. W. Lyons, M. S. Sanford, Chem.
Rev. 2010, 110, 1147; d) H. Li, B.-J. Li, Z.-J. Shi, Catal.
Sci. Technol. 2011, 1, 191.
2-Chloro-3-(2,6-dimethylphenyl)quinazolin-4(3H)-one (1a)
was mixed with Pd(PPh3)4 (5.0 mol%), sodium carbonate
AHCTUNGTRENNUNG
(2.0 equiv.) and PivNHOH (30 mol%). Under an argon at-
mosphere, chlorobenzene (0.1M) was added to the mixture.
The reaction mixture was stirred at 1208C for 3 h until the
starting material was completely consumed. The resulting
mixture was filtered through celite and concentrated under
reduced pressure. The obtained residue was purified by
silica gel column chromatography (n-hexane/ethyl acetate)
to give 10-methylindoloACHTUNTGRNEUNG[2,1-b]quinazolin-12(6H)-one (2a) as
a solid; yield: 76%; mp 208–2108C. 1H NMR (500 MHz,
CDCl3): d=8.27 (dd, 1H, J=8.0, 1.5 Hz), 7.67 (ddd, 1H, J=
8.5, 7.5, 1.5 Hz), 7.59 (d, 1H, J=8.0 Hz), 7.41 (ddd, 1H, J=
8.0, 7.0, 1.0 Hz), 7.21–7.12 (m, 3H), 4.13 (s, 2H), 2.65 (s,
3H); 13C NMR (125 MHz, CDCl3): d=159.7, 158.1, 146.9,
139.7, 134.2, 132.4, 128.0, 127.6, 127.1, 126.6, 126.5, 126.2,
121.9, 121.7, 36.4, 23.7; IR (ATR): n=3069, 2928, 1724,
1699, 1585, 1464, 1307, 1178, 753, 687 cmÀ1; MS (FAB):
m/z=249 (M+H)+; HR-MS: m/z=249.1027, calcd. for
C16H13N2O (M+H)+: 249.1028.
[13] M. Zhang, A.-Q. Zhang, Y. Peng, J. Organomet. Chem.
2013, 723, 224.
[14] Recent examples, see: a) J. J. Neumann, S. Rakshit, T.
Drçge, F. Glorius, Angew. Chem. 2009, 121, 7024;
Angew. Chem. Int. Ed. 2009, 48, 6892; b) S. Rousseaux,
S. I. Gorelsky, B. K. W. Chung, K. Fagnou, J. Am.
Chem. Soc. 2010, 132, 10692; c) K. J. Stowers, K. C.
Fortner, M. S. Sanford, J. Am. Chem. Soc. 2011, 133,
6541; d) M. Nakanishi, D. Katayev, C. Besnard, E. P.
Kꢁndig, Angew. Chem. 2011, 123, 7576; Angew. Chem.
Int. Ed. 2011, 50, 7438; e) P. Novꢂk, A. Correa, J. Gal-
lardo-Donaire, R. Martin, Angew. Chem. 2011, 123,
12444; Angew. Chem. Int. Ed. 2011, 50, 12236; f) S.
Rousseaux, B. Liꢃgault, K. Fagnou, Chem. Sci. 2012, 3,
244; g) T. Piou, L. Neuville, J. Zhu, Angew. Chem.
2012, 124, 11729; Angew. Chem. Int. Ed. 2012, 51,
11561; h) T. Saget, N. Cramer, Angew. Chem. 2012, 124,
13014; Angew. Chem. Int. Ed. 2012, 51, 12842; i) T.
Saget, D. Perez, N. Cramer, Org. Lett. 2013, 15, 1354;
j) C. L. Ladd, D. S. Roman, A. B. Charette, Org. Lett.
2013, 15, 1350.
Acknowledgements
This work was supported by a Grant-in-Aid for Scientific Re-
search on Innovative Areas “Molecular Activation Directed
toward Straightforward Synthesis” from the Ministry of Edu-
cation, Culture, Sports, Science and Technology, Japan.
References
[15] a) C. Tsukano, M. Okuno, Y. Takemoto, Angew. Chem.
2012, 124, 2817; Angew. Chem. Int. Ed. 2012, 51, 2763;
b) T. Nanjo, C. Tsukano, Y. Takemoto, Org. Lett. 2012,
14, 4270; c) C. Tsukano, M. Okuno, Y. Takemoto,
Chem. Lett. 2013, 42, 753.
[1] a) J. Bergman, B. Egestad, J.-O. Lindstrçm, Tetrahedron
Lett. 1977, 18, 2625; b) A. M. Tucker, P. Grundt, ARKI-
VOC 2012, 546, and references cited therein; c) C.-W.
Jao, W.-C. Lin, Y.-T. Wu, P.-L. Wu, J. Nat. Prod. 2008,
71, 1275; d) N. K. Utkina, V. A. Denisenko, Tetrahe-
dron Lett. 2007, 48, 4445.
[16] G. Maestri, E. Motti, N. Della Ca’, M. Malacria, E.
Derat, M. Catellani, J. Am. Chem. Soc. 2011, 133, 8574.
À
[17] Cramer and Charette also reported that methine C H
[2] G. Honda, M. Tabata, M. Tsuda, Planta Med. 1979, 37,
functionalization of cyclopropane occurred in the case
of the unsubstituted cyclopropane, respectively, see
refs.[14h–j]
172.
[3] B. Krivogorsky, A. C. Nelson, K. A. Douglas, P.
Grundt, Bioorg. Med. Chem. Lett. 2013, 23, 1032.
[4] V. M. Sharma, P. Prasanna, K. V. A. Seshu, B. Renuka,
C. V. L. Rao, G. S. Kumar, C. P. Narasimhulu, P. A.
[18] M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuse-
ria, M. A. Robb, J. R. Cheeseman, G. Scalmani, V.
Adv. Synth. Catal. 2014, 356, 1533 – 1538
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
1537

COMMUNICATIONS
Chihiro Tsukano et al.
Barone, B. Mennucci, G. A. Petersson, H. Nakatsuji,
M. Caricato, X. Li, H. P. Hratchian, A. F. Izmaylov, J.
Bloino, G. Zheng, J. L. Sonnenberg, M. Hada, M.
Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida,
T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven,
J. A. Montgomery Jr, J. E. Peralta, F. Ogliaro, M. Bear-
park, J. J. Heyd, E. Brothers, K. N. Kudin, V. N. Staro-
verov, R. Kobayashi, J. Normand, K. Raghavachari, A.
Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi,
N. Rega, N. J. Millam, M. Klene, J. E. Knox, J. B. Cross,
V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E.
Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Po-
melli, J. W. Ochterski, R. L. Martin, K. Morokuma,
V. G. Zakrzewski, G. A. Voth, P. Salvador, J. J. Dannen-
berg, S. Dapprich, A. D. Daniels, ꢄ. Farkas, J. B. Fores-
man, J. V. Ortiz, J. Cioslowski, D. J. Fox, Gaussian 09,
Revision B.01, Gaussian, Inc., Wallingford CT, 2009.
[19] a) A. D. Becke, J. Chem. Phys. 1993, 98, 5648; b) C.
Lee, W. Yang, R. G. Parr, Phys. Rev. B 1988, 37, 785;
c) P. J. Stephens, F. J. Devlin, C. F. Chabalowski, M. J.
Frisch, J. Phys. Chem. 1994, 98, 11623.
3
À
[20] A theoretical study of the palladium-catalyzed C
G
H functionalization of carbamoyl chloride has been re-
ported by Fu and co-workers, see: Q. Zhang, H.-Z. Yu,
Y. Fu, Organometallics 2013, 32, 4165.
1538
asc.wiley-vch.de
ꢀ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2014, 356, 1533 – 1538