Cross-dehydrogenative coupling of acetanilides with aromatic aldehydes

Article abstract of DOI:10.1039/c9nj05853b

Potassium bromide mediated cross-dehydrogenative coupling of acetanilides with aromatic aldehydes in the presence of tert-butyl hydroperoxide (TBHP) for the synthesis of imides has been developed. This new and efficient approach was carried out under an air atmosphere at room temperature and the desired products were obtained in good to high yields.

Full text of DOI:10.1039/c9nj05853b

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Cross-Dehydrogenative Coupling of Acetanilides with Aromatic
Aldehydes
Received 00th January 20xx,
Accepted 00th January 20xx
Ebrahim Kianmehr,*a Hadi Afaridouna
DOI: 10.1039/x0xx00000x
Potassium bromide mediated cross-dehydrogenative coupling of acetanilides with aromatic aldehydes in the presence of
tert-butyl hydroperoxide (TBHP) for the synthesis of imides has been developed. This new and efficient approach was
carried out under an air atmosphere at room temperature and the desired products were obtained in good to high yields.
1. Introduction
by Haung et.al in 2013.9c In 2014, Wang and co-workers reported
oxidative C–H/N–H coupling reaction between aldehydes and
Cross-dehydrogenative coupling reactions (CDC) are proved to be
the most powerful and accurate tools for functionalization of
inactivated C−H bonds through the formation of C–X (X = C, N, O, S,
etc.) bonds in a highly productive and atom economy way in
reduced reaction steps and therefore do not necessitate for pre-
functionalization of starting materials.1
amides in the presence of FeBr2 and TBHP.9d In light of these facts
and biological activity and practical applications of imides, the
development of convenient methods for the preparation of this
class of compunds in a synthetically useful manner is of great
interest.
Imides are a class of organic compounds with considerable
technical and commercial importance which are used in the
pharmaceutical, polymer industries and as precursors in organic
synthesis. The imide containing structural motif is frequently
present at the core of bioactive compounds and natural products.2
Due to the importance of imide motifs, significant efforts have been
devoted to develop efficient methods to construct this class of
compounds. Numerous synthetic methodologies for the
construction of imides have been developed in the past decades in
which acylation of amides with acyl chlorides, anhydrides, terminal
alkynes, esters3 and alcohols,4 Mumm rearrangement of isoimides,5
oxidative decarboxylation of amino acids,6 oxidation of amides2r
and carbonylative coupling of aryl halides and amides,7 are the
most common methods. However most of these methods have
some deficiencies such as using stoichiometric amounts of strong
bases and reactive reagents such as acyl halides with low synthetic
efficiencies.8 Transition metal catalyzed cross-dehydrogenative
coupling reactions of amides with aldehydes for the synthesis of
imides has also been reported recently [Scheme1].9 Acylation of
benzamides in the presence of CuBr and N-Bromosuccinimide was
reported by Fu and co-workers in 2008.9a Direct N-acylation of
lactams, oxazolidinones, and imidazolidinones with aldehydes by
using Shvo’s catalyst was reported by Hong and Zhang in 2012.9b
Scheme 1. Transition-metal catalyzed synthesis of imides from amides and
aldehydes as the acylation reagents.
As
a continuation of our ongoing interest in the field of
functionalization through CDC cross-coupling reactions,10 herein we
describe a transition metal-free, simple, mild and economic
method for direct acylation of acetanilides with aromatic aldehydes
as the easily available acylating source via CDC cross-coupling
reaction in the presence of potassium bromide and TBHP as the
oxidant at room temperature.
Synthesis
of
imides
through
palladium-catalyzed
C-H
functionalization of aldehydes with secondary amides was reported
2. Results and discussion
a. School of Chemistry, College of Science, University of Tehran, Tehran 1417614411,
Iran. E-mail addresses: kianmehr@khayam.ut.ac.ir
† Footnotes relating to the title and/or authors should appear here.
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
Our initial investigation began with acetanilide (1a) and
benzaldehyde (2a) as the standard substrates (Table 1). Various
conditions were screened to optimize the reaction conditions. The
control experiment showed that KBr is of crucial importance for this
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reaction, and the desired product 3a was not obtained in the Commonly used organic solvents such as DMSO, DMFV,ieDwCAMrti,clEetOOnAlince,
absence of KBr (Table 1, entries 1-5). The reaction was also tested CH3CN, DCE, CHCl3 and water were screened. Dichloromethane
DOI: 10.1039/C9NJ05853B
with different KBr loadings, and the results showed that 1.0 (DCM) gave the best yields and solvents such as CH3CN, CHCl3 and
equivalent of the KBr was the best choice for completing the DCE (1,2-dichloroethane) gave moderate yields of the product
reaction (Table 1, entry 4). Decreasing the amount of reagent from (Table 1, entries 11-13) and no reaction took place when H2O,
1.0 equivalent to 10 mol% led to insufficient outcomes and DMSO, DMF or EtOAc were used as the solvent. The reaction was
unfortunately, the reaction was not successful with the catalytic also examined in the presence of transition-metal catalysts. The
amounts of the KBr salt (Table 1, entries 1-3). Furthermore, results showed that a catalytic amount of KBr (10 mol%) is sufficient
increasing the amount of KBr to more than 1.0 equivalent did not to obtain 78 % of the desired product 3a when catalytic amount of
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improve the reaction efficiency (Table 1, entries 6-7).
Table 1. Optimization of the reaction conditions. a
nickel chloride (10 mol%) is used under the optimized reaction
conditions (Table 1, entry 14). To our surprise, catalytic amount of
NiBr2 (10 mol%) improved the yield to 83% even in the abscence of
KBr (Table 1, entry 15). Other catalysts such as Ni(OAc)2, Ni(SO4)2,
were totally ineffective in enhancing the reaction yield and
diminished the reaction progress.
The reaction was also investigated at different temperatures and
times and to our delight the best results were obtained at room
temperature in 12 h. With the results obtained from the
optimization of the reaction conditions, two procedures (A and B)
could be suggested as the standard reaction conditions, procedure
A: acetanilides (0.5 mmol), aldehydes (3.0 eqiuv.), KBr (1.0 equiv.),
TBHP (3.0 equiv.), DCM (2.0 mL) at room temperature for 12 hours
(entry 11) and procedure B: acetanilides (0.5 mmol), aldehydes (3.0
eqiuv.), NiBr2 (10 mol%) , TBHP (3.0 equiv.), DCM (2.0 mL) at room
temperature for 12 hours (entry 15). Therefore to explore the
substrate scope of the reaction, procedure A was preferred, as a
transition metal-free method, and a variety of combinations of
substrates were examined under this optimal reaction condition
and the results are summarized in Table 2.
Reagent (equiv./mol
%)
Oxidant
(equiv.)
Yield
(%)
Entry
Solvent
1
2
KBr (10 mol%)
KBr (10 mol%)
KBr (0.5 equiv.)
KBr (1.0 equiv.)
-
TBHP (2.0)
TBHP (3.0)
TBHP (3.0)
TBHP (3.0)
TBHP (3.0)
TBHP (3.0)
TBHP (3.0)
-
DCE
DCE
18
25
53
68
0
3
DCE
4
DCE
5
DCE
6
KBr (2.0 equiv.)
KBr (3.0 equiv.)
KBr (1.0 equiv.)
KBr (1.0 equiv.)
KBr (1.0 equiv.)
KBr (1.0 equiv.)
KBr (1.0 equiv.)
KBr (1.0 equiv.)
DCE
68
59
0
7
DCE
8
DCE
Substrates with both electron-donating and electron-withdrawing
groups on the aryl ring were well tolerated for this reaction,
affording the desired imides 3a-3n with good to high yields.
Notably, the electron-donating groups, such as -CH3, and -OCH3
performed a higher activity, affording the corresponding products
3b, 3c and 3d in 88-97% yields and electron-withdrawing groups,
such as Cl and Br showed less reactivity to the reaction, producing
the desired products (3e-3h) in 62-78% yields. The heteroaryl
aldehydes were also investigated and produced the desired
products (3o-3q) in 75-83% yields. It should be noted that the
reaction was also successful with ortho-substituted substrates and
the corresponding products 3l, 3m were obtained in 73 and 78%
yields. Unfortunately, the reaction was not successful with aliphatic
aldehydes such as propionaldehyde. The reaction was also
investigated in the presence of other acylating agents such as
toluene, benzyl alcohol, benzyl chloride and benzyl bromide
(Scheme 2). Gratifyingly, when benzyl alcohol was used instead of
benzaldehyde under otherwise identical reaction conditions the
acylated product (3a) was obtained in 82% yield. By using toluene,
benzyl chloride or bromide as the acylating agents, satisfactory
yields of the product were obtained at higher temperatures of 110
and 120°C, respectively (Scheme 2).
9
TBHP (1.0)
TBHP (5.0)
TBHP (3.0)
TBHP (3.0)
TBHP (3.0)
DCE
47
61
92
43
74
10
11
12
13
DCE
DCM
CH3CN
CHCl3
NiCl2 (10 mol%) & KBr
(10 mol%)
14
TBHP (3.0)
DCM
78
15
NiBr2 (10 mol%)
TBHP (3.0)
DCM
83
a
Acetanilide (0.5 mmol), benzaldehyde (1.5 mmol, 3.0 equiv.), reagent or
catalyst (equiv. or mol%), oxidant (equiv.), solvent (2.0 mL) were stirred at
room temperature for 12 h.
Effectiveness of the oxidant was also examined. TBHP was the most
suitable oxidant in this reaction and other oxidants such as DTBP,
H2O2, K2S2O8, Na2S2O8 and (NH4)2S2O8 were not effective and no
product was obtained in the absence of oxidant (Table 1, entry 8).
The amount of TBHP was also investigated, and the results showed
that the best yield was obtained with 3.0 equiv. of TBHP (Table 1,
entries 9-11). The reaction was also tested with NaBr and NBS
instead of KBr, as the bromine sources. With NaBr the desired
product was obtained in lower yield of 66 % and the reaction was
not successful with NBS.
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Table 2. KBr mediated N-acylation of acetanilides with aromatic
aldehydes.[a]
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Scheme 2. Different acylating agents used under the optimized reaction
conditions. (Reactions at elevated temperatures were carried out in sealed
tubes)
Although the mechanism of this reaction has not been established
11
experimentally, but on the basis of previous chemistry,9d,
a
possible mechanism for this cross-coupling reaction using
procedure A, is proposed in Scheme 3.
a
Reaction conditions: Acetanilides (0.5 mmol), aldehydes (3.0 eqiuv., 1.5 Scheme 3. Possible mechanism for the reaction by using procedure A.
mmol), KBr (1.0 equiv.), TBHP (3.0 equiv., 1.5 mmol), DCM (2.0 mL) were
To prove the radical mechanism, a control reaction that involves the
stirred at room temperature for 12 h.
use of 2,6-di-tert-butyl-4-methylphenol (BHT) as a radical scavenger
was performed. When 1a was treated in the presence of butylated
hydroxytoluene (3 equiv.) no desired product 3a was observed
(Scheme 4). To prove the roll of benzoyl bromide, reaction of
benzaldehyde (2a) with KBr and TBHP was investigated in DCM at
room temperature and the formation of benzoyl bromide was
determined by Gc-MS analysis. Also, when the reaction of
acetanilide (1a) with benzoyl bromide was investigated in the
absence of KOH no desired product was obtained in 24 hours.
Based on the above results, a plausible mechanism for the reaction
was proposed in Scheme 3. Initially bromine, tert-butoxy radical and
KOH are produced by reaction of KBr with tert-butyl
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hydroperoxide11d. Next, benzoyl radical intermediate A is generated
in situ by hydrogen-atom abstraction from benzaldehyde in the
presence of t-butoxy radical under the reaction conditions. Then,
the acyl radical reacts with free bromine which is generated in situ
and leads to the formation of benzoyl bromide9d. Finally, an
acylation reaction occurs between acetanilide and benzoyl bromide
in the presence of KOH to form the desired product. The effect of
NiBr2 as the catalyst, in procedure B, which causes the reaction to
be carried out in the absence of KBr is under investigation.
References
View Article Online
1.
(a) K. L. Hull and M. S. Sanford, JDAOCSI:,102.0100739, /1C299N,J1051895034B-
11905; (b) D. R. Stuart and K. Fagnou, Science, 2007, 316,
1172-1175; (c) J. A. Ashenhurst, Chem. Soc. Rev., 2010, 39,
540-548; (d) T. W. Lyons and M. S. Sanford, Chem. Rev.,
2010, 110, 1147-1169; (e) C.-L. Sun, B.-J. Li and Z.-J. Shi,
Chem. Rev., 2010, 111, 1293-1314; (f) S. H. Cho, J. Y. Kim,
J. Kwak and S. Chang, Chem. Soc. Rev., 2011, 40, 5068-
5083; (g) W. R. Gutekunst and P. S. Baran, Chem. Soc.
Rev., 2011, 40, 1976-1991; (h) C. Liu, H. Zhang, W. Shi and
A. Lei, Chem. Rev., 2011, 111, 1780-1824; (i) W. Shi, C. Liu
and A. Lei, Chem. Soc. Rev., 2011, 40, 2761-2776; (j) C. S.
Yeung and V. M. Dong, Chem. Rev., 2011, 111, 1215-1292;
(k) P. B. Arockiam, C. Bruneau and P. H. Dixneuf, Chem.
Rev., 2012, 112, 5879-5918; (l) T. A. Ramirez, B. Zhao and
Y. Shi, Chem. Soc. Rev., 2012, 41, 931-942; (m) Z. Shi, C.
Zhang, C. Tang and N. Jiao, Chem. Soc. Rev., 2012, 41,
3381-3430; (n) C. Zhang, C. Tang and N. Jiao, Chem. Soc.
Rev., 2012, 41, 3464-3484; (o) X. Shang and Z.-Q. Liu,
Chem. Soc. Rev., 2013, 42, 3253-3260; (p) M.-L. Louillat
and F. W. Patureau, Chem. Soc. Rev., 2014, 43, 901-910;
(q) C. Liu, J. Yuan, M. Gao, S. Tang, W. Li, R. Shi and A. Lei,
Chem. Rev., 2015, 115, 12138-12204; (r) H. Yi, G. Zhang,
H. Wang, Z. Huang, J. Wang, A. K. Singh and A. Lei, Chem.
Rev., 2017, 117, 9016-9085.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
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40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
2.
(a) E.-S. Kim, K. Y. Park, J.-M. Heo, B. J. Kim, K. D. Ahn and
J.-G. Lee, Ind. Eng. Chem. Res., 2010, 49, 11250-11253; (b)
T. Pacher, A. Raninger, E. Lorbeer, L. Brecker, P. P.-H. But
and H. Greger, J. Nat. Prod., 2010, 73, 1389-1393; (c) C. S.
Schindler, P. M. Forster and E. M. Carreira, Org. Lett.,
2010, 12, 4102-4105; (d) L. Raj, T. Ide, A. U. Gurkar, M.
Foley, M. Schenone, X. Li, N. J. Tolliday, T. R. Golub, S. A.
Carr, A. F. Shamji, A. M. Stern, A. Mandinova, S. L.
Schreiber and S. W. Lee, Nature, 2011, 475, 231; (e) J.
Sperry, Synthesis, 2011, 2011, 3569-3580; (f) Y.-J. Bian, C.-
Y. Chen and Z.-Z. Huang Chem. Eur. J., 2013, 19, 1129-
1133; (g) H. Lavrard, F. Rodriguez and E. Delfourne, Biorg.
Med. Chem., 2014, 22, 4961-4967; (h) Y. Schmidt, M. van
der Voort, M. Crüsemann, J. Piel, M. Josten, H.-G. Sahl, H.
Miess, J. M. Raaijmakers and H. Gross, ChemBioChem,
2014, 15, 259-266; (i) H. Yu and Y. Zhang, Eur. J. Org.
Chem., 2015, 2015, 1824-1828; (j) H. Aruri, U. Singh, S.
Kumar, M. Kushwaha, A. P. Gupta, R. A. Vishwakarma and
P. P. Singh, Org. Lett., 2016, 18, 3638-3641; (k) S.
Thompson, S. A. McMahon, J. H. Naismith and D.
O’Hagan, Bioorg. Chem., 2016, 64, 37-41; (l) C. S. Digwal,
U. Yadav, P. V. S. Ramya, S. Sana, B. Swain and A. Kamal, J.
Org. Chem., 2017, 82, 7332-7345.
Scheme 4. Control experiments.
3. Conclusions
In conclusion, an efficient method for the synthesis of imides
through N-acylation of acetanilides was developed. This method
provides an economical, direct and simple acylation procedure by
using easily available acylation reagents and avoids ineffective steps
for pre-functionalization of starting materials. This facile and
practical oxidative cross-coupling reaction which is carried out in
the presence of an efficient reagent system (KBr/TBHP), is
insensitive to air or moisture and tolerates a wide range of electron-
donating and electron-withdrawing functional groups and
generates the corresponding products in good to high yields at
room temperature. Different acylating agents such as toluenes,
benzyl alcohols and benzyl halides can be used under the reaction
conditions and produce the desired acylated products in good
yields.
3.
4.
(a) M. B. Andrus, W. Li and R. F. Keyes, Tetrahedron Lett.,
1998, 39, 5465-5468; (b) A. Giovannini, D. Savoia and A.
Umani-Ronchi, J. Org. Chem., 1989, 54, 228-234; (c) X. Jin,
K. Yamaguchi and N. Mizuno, Chem. Lett., 2012, 41, 866-
867; (d) D. Savoia, V. Concialini, S. Roffia and L. Tarsi, J.
Org. Chem., 1991, 56, 1822-1827.
K. Kataoka, K. Wachi, X. Jin, K. Suzuki, Y. Sasano, Y.
Iwabuchi, J.-y. Hasegawa, N. Mizuno and K. Yamaguchi,
Chem. Sci, 2018, 9, 4756-4768.
Conflicts of interest
There are no conflicts to declare.
Acknowledgements
We gratefully acknowledge the financial support from the
Research Council of the University of Tehran.
5.
6.
K. Brady and A. F. Hegarty, J. Chem. Soc., Perkin Trans. 2,
1980, DOI: 10.1039/P29800000121, 121-126.
W. Huang, M. Wang and H. Yue, Synthesis, 2008, 2008,
1342-1344.
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
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Page 5 of 6
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Please do not adjust margins
Journal Name
ARTICLE
1
2
3
4
5
6
7
8
9
7.
(a) H. Li, K. Dong, H. Neumann and M. Beller, Angew.
View Article Online
DOI: 10.1039/C9NJ05853B
Chem., 2015, 127, 10377-10381; (b) Y. Li, F. Zhu, Z. Wang,
J. Rabeah, A. Brückner and X. F. Wu, ChemCatChem, 2017,
9, 915-919.
(a) Y. Li, Y. Wang and J. Wang, Russ. J. Org. Chem., 2008,
44, 358-361; (b) L. Wang, H. Fu, Y. Jiang and Y. Zhao,
Chem. Eur. J., 2008, 14, 10722-10726; (c) X. Li, Y. Fang, P.
Deng, J. Hu, T. Li, W. Feng and L. Yuan, Org. Lett., 2011,
13, 4628-4631; (d) H. Yu and Y. Zhang, Eur. J. Org. Chem.,
2015, 2015, 1824-1828.
8.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
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38
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41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
9.
(a) L. Wang, H. Fu, Y. Jiang and Y. Zhao, Chem. Eur. J.,
2008, 14, 10722-10726; (b) J. Zhang and S. H. Hong, Org.
Lett., 2012, 14, 4646-4649; (c) Y. J. Bian, C. Y. Chen and Z.
Z. Huang, Chem. Eur. J, 2013, 19, 1129-1133; (d) J. Wang,
C. Liu, J. Yuan and A. Lei, Chem. Commun., 2014, 50, 4736-
4739.
(a) E. Kianmehr, S. Kazemi and A. Foroumadi,
Tetrahedron, 2014, 70, 349-354; (b) E. Kianmehr, N.
Faghih and K. M. Khan, Org. Lett., 2015, 17, 414-417; (c) E.
Kianmehr, A. Pakbaznia, N. Faghih and A. Foroumadi,
Tetrahedron, 2017, 73, 1407-1412; (d) E. Kianmehr and M.
Gholamhosseyni, Eur. J. Org. Chem., 2018, 2018, 1559-
1566.
(a) N. Narender, P. Srinivasu, M. Ramakrishna Prasad, S. J.
Kulkarni and K. V. Raghavan, Synth. Commun., 2002, 32,
2313-2318; (b) N. Narender, K. V. V. Krishna Mohan, R. V.
Reddy, P. Srinivasu, S. J. Kulkarni and K. V. Raghavan, J.
Mol. Catal. A: Chem., 2003, 192, 73-77; (c) K. Rajender
Reddy, M. Venkateshwar, C. Uma Maheswari and P.
Santhosh Kumar, Tetrahedron Lett., 2010, 51, 2170-2173.
10.
11.
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A practical, versatile, and efficient method for N-acylation of acetanilides with aromatic aldehydes,
benzyl halides, benzyl alcohols and toluenes as the acylating agents has been described.