One-pot insertion of chalcones into the benzoylacetone backbone

Article abstract of DOI:10.1007/s13738-015-0705-x

Interaction of 1-phenylbutane-1,3-dione and chalcones in the presence of a base gives, in one step, good to high yields cyclic and unusual acyclic insertion products in ratios which depend on substrate, catalyst, and reaction conditions. All the synthesiz

Full text of DOI:10.1007/s13738-015-0705-x

J IRAN CHEM SOC
DOI 10.1007/s13738-015-0705-x
ORIGINAL PAPER
One‑pot insertion of chalcones into the benzoylacetone backbone
Farid N. Naghiyev1 · Atash V. Gurbanov1 · Abel M. Maharramov1 ·
Ibrahim G. Mamedov1 · Mirze A. Allahverdiyev1 · Kamran T. Mahmudov1,2
Received: 30 December 2014 / Accepted: 16 July 2015
© Iranian Chemical Society 2015
Abstract Interaction of 1-phenylbutane-1,3-dione and
chalcones in the presence of a base gives, in one step, good
to high yields cyclic and unusual acyclic insertion products
in ratios which depend on substrate, catalyst, and reaction
conditions. All the synthesized compounds are character-
many instances leads to ring systems with asymmetric car-
bon atoms, thus allowing an easy preparation of structural
motifs found in a variety of natural products [1].
Chalcones are known substrates where different sub-
stitution patterns on the two aromatic rings of 1,3-diphe-
nyl-2-propen-1-one are linked by a three carbon α,β-
unsaturated carbonyl system which belongs to the flavonoid
family [10–12]. Chalcones exhibit a wide spectrum of bio-
logical activities including antimicrobial, anticancer, anti-
protozoal, antiulcer, and antiinflammatory ones [10, 12].
The coupling products of AMC with chalcones (Scheme 1)
not only constitute components of biologically active natu-
ral products, but also serve as starting materials for further
important organic transformations [13]. Michael additions
of AMC to chalcone are usually catalyzed by bases, such
as piperidine, CH3ONa, NaOH, Ba(OH)2, ionic liquids,
etc. [14–19]. Due to the presence of bases, the cycliza-
tion of the extended ketones (Scheme 1) usually proceeds
smoothly giving cyclic products with asymmetric car-
bon atoms (Routes I and III, Scheme 2). However, to our
knowledge, no further ring transformation in such type of
syntheses has been reported but was observed in the cur-
rent study. Hence, herein we report results on the catalyst,
solvent, and substituent depending couplings of benzoylac-
etone with different chalcones.
1
ized using IR, H and 13C NMR spectroscopies, ESI–MS,
and single-crystal X-ray diffraction (for one compound)
analysis.
Keywords Michael addition · Chalcone ·
Benzoylacetone · Active methylene compounds
Introduction
The Michael addition of a stabilized carbon nucleophile
or a heteroatom-centered nucleophile to electron-deficient
olefins is a classical way to construct C–C or C–heteroatom
bonds in organic synthesis [1–5]. Active methylene com-
pounds (AMC) are widely used as carbon nucleophiles in
the coupling with e.g., chalcone (1,3-diphenyl-2-propen-
1-one) to form extended ketones (Scheme 1) [6–9]. An
intramolecular cyclization of these coupling products in
Electronic supplementary material The online version of this
article (doi:10.1007/s13738-015-0705-x) contains supplementary
material, which is available to authorized users.
Experimental section
* Kamran T. Mahmudov
kamran_chem@mail.ru; kamran_chem@yahoo.com
Materials and instrumentation
1
Department of Chemistry, Baku State University, Z. Xalilov
All the chemicals were obtained from commercial sources
(Aldrich) and used as received. The 1H and 13C NMR spec-
tra were recorded at room temperature on a Bruker System-
AV300 (UltraShieldTM Magnet) spectrometer operating
Str. 23, 1148 Baku, Azerbaijan
2
Centro de Química Estrutural, Instituto Superior Técnico,
Universidade de Lisboa, Av. Rovisco Pais, 1049–001 Lisbon,
Portugal
1 3

J IRAN CHEM SOC
solution. The compounds were observed in the positive
mode (capillary voltage = 80–105 V).
Synthesis of 1 and 2
To a solution of 1,3-diphenyl-2-propen-1-one (0.400 g,
1.90 mmol) in benzene (15 mL) 1-phenylbutane-1,3-di-
one (0.300 g, 1.90 mmol) and 0.05 mL piperidine (dry in
the case of 1) were added in this order and the mixture
was stirred at room temperature for 24 h. After comple-
tion of the reaction (as monitored by TLC), the solvent
was removed under reduced pressure, and the residue was
washed with hot water; then, the products were recrys-
tallized from ethanol (yield, 72 and 76 % for 1 and 2,
respectively).
Scheme 1 Michael addition of AMC to chalcone
at 300.130 and 75.468 MHz for proton and carbon-13,
respectively. The chemical shifts are reported in ppm using
tetramethylsilane as the internal reference. Infrared spec-
tra (4000–400 cm−1) were recorded on a BIO-RAD FTS
3000MX instrument in KBr pellets. Carbon, hydrogen,
and nitrogen elemental analyses were done using a “2400
CHN Elemental Analyzer” by Perkin Elmer. Electrospray
mass spectra were run with an ion trap instrument (Varian
500-MS LC Ion Trap Mass Spectrometer) equipped with
an electrospray (ESI) ion source. For electrospray ioniza-
tion, the drying gas and flow rate were optimized according
to the particular sample with 35 p.s.i. nebulizer pressure.
Scanning was performed from m/z 100 to 1200 in methanol
6′‑Benzoyl‑1′,6′‑dihydro‑[1,1′:3′,1′′‑terphenyl]‑5′(2′H)‑
one (1)
Mp 173 °C; IR (KBr): 2926, 2966, 3006 and 3062
ν(CH), 1610, 1650 and 1676 ν(C=O) cm−1; 1H NMR
Scheme 2 Reaction of
1-phenylbutane-1,3-dione with
chalcones
1 3

J IRAN CHEM SOC
2
(300.130 MHz, DMSO-d6): 3.12 (dd, 2H, CH2, JH–
1-phenylbutane-1,3-dione (0.300 g, 1.90 mmol) and
0.05 mL piperidine were added, and the reaction mixture
was stirred for 24 h at room temperature and monitored
by TLC. After that the solvent was evacuated to 2/3 of its
initial volume; the compound 3 precipitated from the thus
concentrated solution, being then filtered off and recrystal-
lized from methanol (yield 46 %, or 31 % if ethanol was
used as a solvent). In the case of compound 4, the liquid
part of the reaction mixture was completely evacuated and
the solid residue was recrystallized from ethanol to give
pure product 4 with yield 23 %. Compound 5 with 48 %
yield was obtained by the same procedure with ethanol
used instead of methanol (Route IV, Scheme 2).
3
3
= 16.3 Hz, JH–H = 8.2 Hz); 3.91 (t, 1H, CH, JH–
H
3
= 12.4 Hz); 5.52 (d, 1H, CH, JH–H = 12.4 Hz); 6.56
H
(s, 1H, CH =); 7.1–7.92 (m, 15Harom, 3Ar). 13C NMR
(75.468 MHz, DMSO-d6): 199.4, 197.5, 159.6, 142.7, 138.3,
137.8, 133.7, 130.9, 129.3, 129.1, 128.8, 128.0, 127.2, 126.9,
124.2, 58.2, 43.9, 36.4; MS (ESI): m/z: 353.15 [M + H]+.
Piperidin‑1‑ium 3‑hydroxy‑7‑oxo‑3,5,7‑
triphenylheptanoate (2)
Mp 108 °C; IR (KBr): 3281 ν(OH), 2856, 2936, 3031,
3053, 3084 and 3104 ν(CH), 1685 ν(C=O) cm−1; H NMR
1
(300.130 MHz, DMSO-d6): 1.14-1.39 (m, 6H, 3CH2); 2.18
2
3
and 2.32 (d-t, 2H, CH2, JH–H = 14.1 Hz, JH–H = 8.9 Hz);
Method 2
3
2.43 and 2.72 (d, 2H, CH2, JH–H = 8.9 Hz); 3.12 (m, 4H,
2CH2); 3.48 (m, 1H, CH); 3.64 and 3.12 (d-m, 2H, CH2, 3JH–
To a solution of 1,3-diphenyl-2-propen-1-one (0.400 g,
1.90 mmol) in methanol (15 mL) were added 1-phenylb-
utane-1,3-dione (0.300 g, 1.90 mmol) and 5 mg CH3ONa.
The mixture was then stirred for 24 h while reaction was
monitored by TLC. The solvent was removed under
reduced pressure, and the residue was recrystallized from
ethanol to give 4 in 65 % yield (Route V, Scheme 2).
= 15.21 Hz); 6.28 (s, 1H, OH); 6.89-7.69 (m, 15H, 3Ar).
H
13C NMR (75.468 MHz, DMSO-d6): 198.2, 169.2, 144.9,
144.3, 136.0, 131.5, 127.3, 127.1, 127.07, 126.4, 125.6, 124.9,
124.2, 74.9, 48.2, 45.6, 45.03, 41.9, 41.4, 36.7, 33.6, 25.2,
24.4, 23.3; MS (ESI): m/z: 387.16 [M-piperidin-1-ium]−.
Synthesis of 3
Method 3
To a solution of 1,3-diphenyl-2-propen-1-one (0.400 g,
1.90 mmol) in methanol (15 mL) 1-phenylbutane-1,3-dione
(0.300 g, 1.90 mmol) and 0.05 mL (C2H5)3N were added in
this order. The mixture was then stirred for 24 h while the
course of reaction was monitored by TLC. After the reac-
tion completion, the solvent was removed under reduced
pressure, and the residue was recrystallized from ethanol to
give 3 in 67 % yield.
5 mmol of 3 was dissolved in 15 mL methanol and then
5 mg CH3ONa was added and the solution was stirred for
24 h at room temperature. After 3 days (as monitored by
TLC) the solvent was removed under reduced pressure, and
the residue was recrystallized from ethanol to give pure 4
with yield 87 % (Scheme 4).
Methyl 3‑hydroxy‑7‑oxo‑3,5,7‑triphenylheptanoate (4)
2‑Benzoyl‑5‑hydroxy‑3,5‑diphenylcyclohexanone (3)
Mp 134 °C; IR (KBr): 3340 and 3530 ν(OH), 2845, 2896,
2926, 2942, 2951, 3004, 3029, 3060 and 3088 ν(CH),
Mp 205 °C; IR (KBr): 3420 and 3599 ν(OH), 2922, 2946,
1
2970, 3025, 3056 and 3084 ν(CH), 1672 ν(C=O) cm−1
;
1680 and 1724 ν(C=O) cm−1; H NMR (300.130 MHz,
1H NMR (300.130 MHz, DMSO-d6): 2.00 and 2.64 (d-t,
DMSO-d6): 2.31 (m, 2H, CH2); 2.83 (s, 2H, CH2); 3.04
2
3
2H, CH2, JH–H = 13.2 Hz, JH–H = 7.5 Hz); 2.41 and
(m, 1H, CH); 3.44 (s, 3H, CH3O); 3.66 and 3.39 (d-m, 2H,
3
3
2
3.52 (d, 2H, CH2, JH–H = 18.2 Hz); 4.10 (t, 1H, CH, JH–
H = 7.5 Hz); 5.51 (d, 1H, CH, 3JH–H = 10.9 Hz); 5.76 (s, 1H,
OH); 7.11–7.92 (m, 15Harom, 3Ar). 13C NMR (75.468 MHz,
DMSO-d6): 207.9, 198.0, 148.4, 143.8, 137.7, 133.6, 129.1,
128.8, 128.5, 128.4, 128.0, 127.7, 127.2, 126.8, 124.9, 76.2,
61.7, 54.1, 46.5, 42.4; MS (ESI): m/z: 371.24 [M + H]+.
CH2, JH–H = 14.7 Hz); 5.39 (s, 1H, OH); 6.88–7.81 (m,
15Harom, 3Ar). 13C NMR (75.468 MHz, DMSO-d6): 199.4,
171.2, 146.5, 145.6, 137.0, 133.3, 128.9, 128.4, 128.2,
128.1, 127.6, 126.8, 126.0, 125.9, 75.7, 51.5, 48.9, 48.5,
45.6, 37.7; MS (ESI): m/z: 403.27 [M + H]+.
Ethyl 3‑hydroxy‑7‑oxo‑3,5,7‑triphenylheptanoate (5)
Synthesis of 4 and 5
Mp 200 °C; IR (KBr): 3537 ν(OH), 2907, 2920, 2941,
2963, 2983, 3030, 3055 and 3084 ν(CH), 1675 and 1719
Method 1
1
ν(C=O) cm−1; H NMR (300.130 MHz, DMSO-d6): 0.95
3
To 15 mL of methanol (ethanol in the case of 5) solution
of 1,3-diphenyl-2-propen-1-one (0.400 g, 1.90 mmol)
(t, 3H, CH3, JH–H = 8.1 Hz); 2.32 (m, 2H, CH2); 2.81 (d,
2H, CH2); 3.06 (m, 1H, CH); 3.69-3.40 (d-m, 2H, CH2,
1 3

J IRAN CHEM SOC
3
2JH–H = 14.6 Hz); 3.89 (k, 2H, CH2O, JH–H = 8.1 Hz);
methanol and 5 mg of CH3ONa was added to this solution.
Reaction mixture was stirred at room temperature for 24 h
(as monitored by TLC). Then the solvent was removed
under reduced pressure, and the resulting precipitate of 8
was filtrated off and washed with ethanol (yield, 79 %).
5.37 (s, 1H, OH); 6.89–7.79 (m, 15Harom, 3Ar). 13C NMR
(75.468 MHz, DMSO-d6): 199.4, 170.8, 146.5, 145.5,
137.0, 133.3, 128.9, 128.4, 128.2, 128.0, 127.6, 127.2,
126.9, 126.0, 75.8, 59.9, 49.0, 48.7, 45.6, 37.7, 14.3; MS
(ESI): m/z: 417.09 [M + H]+.
Ethyl 5′‑oxo‑2′,3′,4′,5′‑tetrahydro‑[1,1′:3′,1′′‑terphenyl]‑
4′‑carboxylate (8)
Synthesis of 6 and 7
3-(4-nitrophenyl)-1-phenylprop-2-en-1-one
(0.400
g,
Mp 164 °C; IR (KBr): 2903, 2946, 2985, 3031 and 3061
1.60 mmol) was dissolved in 15 mL methanol (ethanol in
the case of 7) and refluxed for 5 min, then 1-phenylbutane-
1,3-dione (0.260 g, 1.60 mmol) and catalyst (0.05 mL piper-
idine or (C2H5)3N or 0.050 g CH3ONa) were added and the
reaction mixture was stirred at room temperature for 24 h.
After completion of the reaction (as monitored by TLC), the
solvent was removed under reduced pressure, and the resi-
due was washed with hot water and recrystallized from eth-
anol to give pure 6 or 7 with yields, respectively, of 67 and
69 %, with the (C2H5)3N catalyst, 69 and 72 % with piperi-
dine as a catalyst, and 72 and 74 % if CH3ONa was used.
ν(CH), 1606, 1658 and 1735 ν(C=O) cm−1
;
1H NMR
3
(300.130 MHz, DMSO-d6): 0.89 (t, 3H, CH3, JH–
3
= 8.3 Hz); 3.05 (m, 2H, CH2); 3.48 (t, 1H, CH, JH–
H
3
= 8.3 Hz); 3.89 (q, 2H, CH2, JH–H = 8.3 Hz); 4.11 (d,
H
1H, CH, 3JH–H = 11.1 Hz); 3.56 (s, 1H, CH =); 7.23–7.48
(m, 10H, 2Ar). 13C NMR (75.468 MHz, DMSO-d6): 194.8,
169.8, 159.8, 141.9, 137.7, 130.9, 129.3, 128.9, 128.3,
127.6, 126.9, 123.3; MS (ESI): m/z: 321.14 [M + H]+.
X‑ray structure determination
A crystal of 5 was immersed in cryo-oil, mounted in a
Nylon loop, and the intensity data were collected at 296 K
on a Smart Apex II diffractometer using Mo Kα radiation
(λ = 0.71073 Å). The diffraction experiments were carried
out on a Bruker APEX II CCD diffractometer. The program
SHELXTL [20] was used for collecting frames of data,
indexing reflections, and for the determination of the lattice
parameters, SAINTP [21]—for integration of the intensity
of reflections and scaling, SADABS [22]—for absorption
correction, and SHELXTL [20]—for the space group and
structure determination, least-squares refinements on F2.
The crystallographic details are summarized in Table (Elec-
tronic Supplementary Information). Crystallographic data
for the structure reported in this paper have been deposited
with the Cambridge Crystallographic Data Centre as sup-
plementary publication, CCDC (966239) 5. Copies of this
information may be obtained free of charge from The Cam-
bridge Crystallographic Data Centre via www.ccdc.cam.
ac.uk/data_request/cif.
Methyl 3‑hydroxy‑5‑(4‑nitrophenyl)‑7‑oxo‑3,7‑
diphenyl‑heptanoate (6)
Mp 142 °C; IR (KBr): 3528 ν(OH), 2844, 2900, 2918,
2929, 2941, 2959, 3030, 3066 and 3087 ν(CH), 1675 and
1
1717 ν(C=O) cm−1; H NMR (300.130 MHz, DMSO-
d6): 2.33 (m, 2H, CH2); 2.81 (s, 2H, CH2); 3.26 (m, 1H,
CH); 3.43 (s, 3H, CH3O); 3.59 (m, 2H, CH2); 5.39 (s, 1H,
OH); 7.1–7.92 (m, 14Harom, 3Ar). 13C NMR (75.468 MHz,
DMSO-d6): 198.8, 171.1, 154.8, 145.7, 145.4, 136.8, 133.6,
129.1, 128.2, 127.9, 126.7, 125.9, 123.3, 75.3, 51.5, 48.5,
48.2, 45.5, 37.3; MS (ESI): m/z: 448.11 [M + H]+.
Ethyl 3‑hydroxy‑5‑(4‑nitrophenyl)‑7‑oxo‑3,7‑
diphenylheptanoate (7)
Mp 116 °C; IR (KBr): 3499 ν(OH), 2940, 2982, 3027,
3067 and 3110 ν(CH), 1671 and 1722 ν(C=O) cm−1; H
1
3
NMR (300.130 MHz, DMSO-d6): 0.96 (t, 3H, CH3, JH–
H = 8.2 Hz); 2.33 (m, 2H, CH2); 2.79 (s, 2H, CH2); 3.28 (m,
1H, CH); 3.59 and 2.35 (d-m, 2H, CH2, 3JH–H = 14.7 Hz);
3.88 (k, 2H, CH2O, 3JH–H = 8.2 Hz); 5.36 (s, 1H, OH); 7.1–
7.91 (m, 14Harom, 3Ar). 13C NMR (75.468 MHz, DMSO-
d6): 198.8, 170.6, 154.8, 145.7, 145.3, 136.8, 133.6, 129.1,
128.2, 127.9, 126.6, 125.9, 123.3, 75.4, 59.9, 48.6, 48.3,
45.5, 37.3, 14.3; MS (ESI): m/z: 462.13 [M + H]+.
Results and discussion
The reactions of chalcones with 1-phenylbutane-1,3-dione
were performed in the presence of different solvents (ben-
zene, methanol, and ethanol) and catalysts, such as piperi-
dine, (C2H5)3N and CH3ONa (Scheme 2). It was observed
that in majority of cases the type of reaction products and
their yield strongly depend on the solvents used and basic-
ity of catalysts. For instance, alcohols play a dual role as
solvents and nucleophilic agents in the synthesis of the acy-
clic compounds 4–7, however, the yields of the products are
Synthesis of 8
338 mg (1 mmol) of ethyl 4-hydroxy-2-oxo-4,6-diphe-
nylcyclohexanecarboxylate was dissolved in 10 mL of
1 3

J IRAN CHEM SOC
Scheme 3 CH3ONa-catalyzed
dehydration (I) and ring open-
ing (II)
lower in alcoholic medium than in benzene (Routes I, II,
and IV, Scheme 2). Moreover, the yield of the acyclic prod-
uct is higher in ethanol (48 %, synthesis of 5) than in meth-
anol (23 %, synthesis of 4) for the piperidine-catalyzed
reaction of 1-phenylbutane-1,3-dione with chalcone (Route
IV). On the other hand, the found unusual fragmentation of
1-phenylbutane-1,3-dione depends on the basic properties
of catalysts: in the presence of more basic CH3ONa only
the insertion product 4 was obtained, while in piperidine
compounds 3 and 4, and in (C2H5)3N exclusively the cyclic
product 3 were isolated (Routes III–V). Purity of catalysts
is also important in this reaction: when unpurified piperi-
dine was used as a catalyst, only the acyclic compound 2
was isolated (Rote II, Scheme 2), which clearly shows a
role of water in the ring opening in compound 1, and sta-
bilization of this salt. However, when 3-(4-nitrophenyl)-1-
phenylprop-2-en-1-one is used as a starting material, result
of the reaction is the same, i.e., an acyclic product with
unusual insertion of the chalcone into the backbone of ben-
zoylacetone is formed (Route VI, Scheme 2). This fact is
possibly related to the higher electron-accepting ability of
–NO2 (its Hammett’s σp constant [23] is 0.78). It should be
noted that, more electron-donating group attached in chal-
cone moiety, such as –OCH3 (σp = −0.27) provides same
products as observed in the case of unsubstituted chalcone.
If other AMCs, such as pentane-2,4-dione, 1,3-diphe-
nylpropane-1,3-dione, and ethyl 3-oxobutanoate were used
instead of 1-phenylbutane-1,3-dione, the formation of acy-
clic products with the unusual fragmentation of diones was
not observed. Hence, the found insertion most probably
occurs through the formation of the cyclic products of the
Michael addition. This is, additionally, proved by interac-
tion of the cyclic products with alcohols in the presence of
a strong base, such as CH3ONa (Scheme 3). In this case,
replacement of –OC2H5 group by –C6H5 in the cyclic sub-
strate (in the synthesis of 4) leads to a ring opening reac-
tion. The observed difference in behavior can be explained
by different electron-withdrawing abilities of the substitu-
ents (values of Hammett’s σp constant [23] are −0.24 for
OC2H5 and −0.01 for C6H5) and bulkiness of phenyl ring.
The structures of all the obtained products were deduced
Fig. 1 X-ray structure of compound 5
X-ray diffraction analysis of compound 5 (Fig. 1). The
mass spectra of these compounds displayed molecular
ion peaks at the appropriate m/z (%) values. The IR spec-
trum of 1–8 showed two bands at 2844–3110 and 1606–
1685 cm−1 due to vibrations of the CH and C=O groups,
respectively, and ester carbonyl at 1717–1735 cm−1 (for
4–8), while ν(OH) of 2–7 reveal at ca. 3281–3599 cm−1
.
1H-NMR spectra of 2–7 in dimethylsulfoxide-d6 solution at
room temperature show a resonance at δ 5.36–6.28, which
can be assigned to the proton of the −OH group. The CH
protons of 1, 3, and 8 were visible as a triplet at δ 3.91
(J = 12.4 Hz), 4.10 (J = 7.5 Hz), 3.48 (J = 8.3 Hz) and
doublets at δ 5.52 (J = 12.4 Hz), 5.51 (J = 10.9 Hz) and
4.11 (J = 11.1 Hz), respectively. The 13C resonance sig-
nals for the carbonyl groups were seen at δ 199.4 and 197.5
(for 1), 198.2 (for 2), 207.9 and 198.0 (for 3), 199.4 (for 4),
199.4 (for 5), 198.8 (for 6), 198.8 (for 7), 194.8 (for 8). The
resonance signals at δ 169.2, 171.2, 170.8, 171.1, 170.6,
and 169.8 for 2, and 4–8, respectively, were attributed to
the ester carbonyls. All the other 13C resonance signals are
also in agreement with the designated structures. Addition-
ally, a molecular structure of 5 (Fig. 1) was determined by
single-crystal X-ray analysis, confirming unambiguously
the structures and stereochemistry of the products.
The following mechanism of the encountered unusual
insertion can be suggested based on the obtained results.
On the first stage, reaction of 1,3-diphenyl-2-propen-1-one
with 1-phenylbutane-1,3-dione in the presence of CH3ONa
gives cyclic product 3 (Scheme 2), which undergoes
1
from their IR, ESI–MS, H and 13C NMR spectra, and
1 3

J IRAN CHEM SOC
widen the scope of the found interesting one-step one-pot
transformation.
Acknowledgments This work has been partially supported by the
Baku State University, Azerbaijan.
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In summary, we have found that 1-phenylbutane-1,3-dione
can undergo an unusual fragmentation upon the Michael
reaction with chalcones which insert into its backbone. The
found transformation depends on basicity of the catalysts
used. Thus, no fragmentation was observed when (C2H5)3N
was applied as a catalyst, while in the presence of piperi-
dine and CH3ONa the acyclic insertion products were
isolated. To our knowledge, this is the first report on such
direct insertion reaction of chalcones into AMCs. Another
notable feature of the reaction is the found one-step one-
pot combination of three substrates in one new rather intri-
cate product with multiple stereogenic carbon atoms. The
insertion products can possess biological activities similar
to chalcones [10–12] or serve as a useful tool for the con-
struction of new coordination and supramolecular archi-
tectures [24]. Further study of reactants and conditions can
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