Synthesis of α-iodoketals from methyl ketones via sustainable and orthogonal tandem catalysis

Article abstract of DOI:10.1039/c2ob27028e

A highly efficient method for the direct synthesis of α-iodoketals from methyl ketones has been developed via sustainable integration of orthogonal tandem catalytic reactions: copper(ii) oxide catalyzed iodination reaction and the subsequent excess or reg

Full text of DOI:10.1039/c2ob27028e

Organic &
Biomolecular Chemistry
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Synthesis of α-iodoketals from methyl ketones via
sustainable and orthogonal tandem catalysis†
Cite this: Org. Biomol. Chem., 2013, 11,
1226
Yan Yang, Meng Gao, Wen-Ming Shu, Liu-Ming Wu, Dong-Xue Zhang and
An-Xin Wu*
Received 17th October 2012,
Accepted 17th December 2012
A highly efficient method for the direct synthesis of α-iodoketals from methyl ketones has been devel-
oped via sustainable integration of orthogonal tandem catalytic reactions: copper(II) oxide catalyzed iodi-
nation reaction and the subsequent excess or regenerated iodine catalyzed regioselective ketalization
reaction.
DOI: 10.1039/c2ob27028e
www.rsc.org/obc
Introduction
In order to maximize synthetic efficiency, great attention has
been paid to the sustainable integration of diverse reactions in
one process via domino or tandem strategies.1 Considering
stoichiometric reagents are still needed for many organic reac-
tions, it is particularly attractive for their stoichiometric bypro-
ducts to be internally recycled to catalyze the subsequent
reaction in one process. Recently, this strategy has been suc-
cessfully implemented in a domino nitroarene reduction/
imine formation/aza Diels–Alder reaction,2a domino nitrogen
protection/imine formation/imine addition reaction,2b domino
Wittig–conjugate–reduction reaction.2c Inspired by these excel-
lent studies, we have recently developed a new synthetic strat-
egy for the synthesis of hydantoins and α-formyloxy by
sustainable integration of coupled domino processes.2d–e
Based on our interests in developing sustainable synthetic
Scheme 1 Sustainable integration of coupled catalytic processes.a
Scheme 2 Our hypothesis for the direct synthesis of α-iodoketals.
strategies, we would like to report herein a novel sustainable iodination of ketals.9,10 Surprisingly, only limited methods are
orthogonal-tandem catalysis strategy,3 in which the excess or available for the direct transformation of ketones into α-iodo-
partly regenerated reagent in the upstream reaction could be ketals,9,11 and their substrates were most limited to saturated
internally recycled to catalyze the downstream reaction aliphatic ketones, probably due to the easy iodination of
(Scheme 1).
carbon–carbon double bonds and lower reactivity of aryl
α-Iodoketals have been used as versatile intermediates in ketones.6 To complement the previous synthetic methods, it is
synthesis of multifunctional organic compounds4 and natural highly desirable to develop a simple and direct method for the
products.5 Correspondingly, several methods have been devel- synthesis of α-iodoketals from aryl/vinyl ketones.
oped for their synthesis, including iodocyclization of alkenes,6
In our previous studies, we have developed a highly
ring-opening of aziridines or oxirines,7 substitution of stannic efficient method for the α-iodination of methyl ketones in
or halogenated ketals,8 acetalization of α-iodoketones,5b,9 and methanol or 2-propanol.12 Encouraged by this result, we won-
dered whether it would be possible for the direct synthesis of
α-iodoketals via sustainable integration of α-iodination and
ketalization in one process via an orthogonal tandem strategy
(Scheme 2). To verify this hypothesis, we would like to report
herein a highly efficient and regioselective method for the
direct synthesis of α-iodoketals from aryl/vinyl methyl ketones,
which have potentially broad applications in organic
synthesis.13
Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of
Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079,
P. R. China. E-mail: chwuax@mail.ccnu.edu.cn; Tel: +86 027 6786 7773
†Electronic supplementary information (ESI) available: Experimental procedures
and compound characterization data. CCDC 884836, 884837 and 885165. For
ESI and crystallographic data in CIF or other electronic format see DOI:
10.1039/c2ob27028e
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Table 2 Scope of substrates with different R1 groupsa
Scheme 3 Synthesis of (Z)-2-arylidene-1-arylbutane-1,3-diones.
Table 1 Optimization of the reaction conditionsa
Entry
R1
4
Yieldb (%)
1
2
3
4
5
6
7
8
9
3aa (C6H5)
4aa
4ba
4ca
4da
4ea
4fa
4ga
4ha
4ia
85
83
82
84
60
72
85
78
73
89
3ba (4-MeC6H4)
3ca (4-MeOC6H4)
3da (4-NO2C6H4)
3ea (1-Naphthyl)
3fa (2-Naphthyl)
3ga (4-ClC6H4)
3ha (4-BrC6H4)
3ia (4-FC6H4)
Entry
CuO (equiv.)
I2 (equiv.)
Temp (°C)
Yieldb (%)
10
3ja (2-Thienyl)
4ja
1
2
3
4
5
6
7
8
1.0
1.5
1.5
1.5
2.0
3.0
1.2
1.2
2.0
3.0
3.0
1.5
1.5
1.5
1.5
1.5
1.5
1.5
1.0
1.2
1.0
0.8
1.2
1.2
2.0
3.0
2.0
2.0
3.0
1.2
1.2
1.2
1.2
1.2
1.2
1.2
60
60
60
60
60
60
60
60
60
60
60
rt
40
80
100
100
100
120
75
85
72
63
80
75
83
78
75
76
74
a Reaction was performed with (Z)-2-arylidene-1-phenylbutane-1,3-
dione 3 (1.0 mmol), CuO (1.5 mmol), and I2 (1.2 mmol) in ethylene
glycol (5 mL) at 60 °C for 5 h. b Isolated yield.
also conducted with different doses of copper(II) oxide and
iodine, but no better results were obtained (entries 3–11). The
temperature also has a significant influence on the reaction
efficiency. No conversion of 3aa was observed at room tempera-
ture (Table 1, entry 12). When the reaction was conducted at
40 or 80 °C, 4aa was obtained in 65% and 80% yield, respecti-
vely (entries 13, 14). Further increasing the reaction tempera-
ture resulted in a significant decrease in the yields (entries
15–18).
Under the optimized reaction conditions (Table 1, entry 2),
the reactivity of substrates 3 with various R1 groups was
initially investigated (Table 2). Pleasingly, the electronic nature
of arylidenes has little influence on the reaction efficiency.
With electron neutral (–H, –Me), electron donating (–OMe) and
electron withdrawing groups (–NO2), the reactions proceeded
smoothly and their corresponding products were obtained in
good yields (entries 1–4, 82–85%). In addition, moderate yields
9
10
11
12
13
14
15d
16e
17
18
c
—
65
80
31
57
63
42
a Reaction conditions: (Z)-2-benzylidene-1-phenylbutane-1,3-dione 3aa
(1.0 mmol), CuO (x mmol) and iodine (x mmol) in 5 mL of ethylene
glycol for 5 h. b Isolated yields. c No desired product was obtained.
d The reaction time was 1 h. e The reaction time was 3 h.
Results and discussion
(Z)-2-Arylidene-1-arylbutane-1,3-diones 3 were first prepared were obtained for sterically hindered substrates (60–72%;
from aldehyde 1 and 1-arylbutane-1,3-dione 2 in excellent entries 5 and 6). Notably, the halogenated substrates (73–85%;
yields according to a modified procedure (Scheme 3).14 Con- entries 7–9) were also compatible under this reaction, which
sidering ethylene glycol could both serve as the reaction could be used for further functionalization.17 Much to our satis-
solvent and reagent for acetal protection,15 we wondered faction, substrate with heteroarylidene group could also give the
whether it would be possible for the direct synthesis of α-iodo- corresponding product in excellent yield (89%; entry 10).
ketals with ethylene glycol as solvent. On the basis of our pre-
Next, the generality of this reaction was expanded to sub-
vious studies on iodination of methyl ketones,12 we first tried strates 3 with different R2 groups, which could also proceed
the experiment using (Z)-2-benzylidene-1-phenylbutane-1,3- efficiently to afford their corresponding products in moderate
dione 3aa as the model substrate in the presence of iodine and to excellent yields (Table 3). Although a moderate yield was
copper(II) oxide with ethylene glycol as the solvent (Table 1). obtained with the sterically hindered 2-naphthyl group (43%,
Fortunately, when the reaction was conducted with 1.0 equiv. entry 2), the halogenated aryl groups were compatible under
of copper(II) oxide and 1.0 equiv. of iodine at 60 °C, the the reaction conditions and good yields were obtained
desired product 4aa was obtained in 75% yield (entry 1) and (73–78%; entries 3–4). To our satisfaction, substrates with
its structure was also clearly confirmed by X-ray diffraction.16 heteroaryl groups could also give their corresponding products
Further exploration showed that the yield was increased to in good to excellent yields (85–88%; entries 5–6).
85% when the equivalent of copper(II) oxide was 1.5 and
Considering 1,3-propanediol is also a popular reagent for
iodine was 1.2 (entry 2). A series of screening experiments were ketone protection,14 the reaction was then conducted with
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Table 3 Scope of substrates with different R2 groupsa
Table 4 Scope of substrates with aryl methyl ketonesa
Entry
R2
2
Yieldb (%) Entry
R3
7
Yieldb (%)
1
2
3
4
5
6
3ab (4-MeC6H4)
3ac (2-Naphthyl)
3ad (4-ClC6H4)
3ae (4-BrC6H4)
3af (2-Furyl)
4ab
4ac
4ad
4ae
4af
82
43
78
73
85
88
1
2
3
4
5
6
7
8
9
6a (C6H5)
7a
7b
7c
7d
7e
7f
7g
7h
7i
36
43
46
52
44
98
84
72
6b (4-ClC6H4)
6c (3,4-ClC6H3)
6d (4-BrC6H4)
6e (4-FC6H4)
6f (4-NO2C6H4)
6g (3-NO2C6H4)
6h (2-NO2C6H4)
6i (4-MeOC6H4)
3ag (2-Thienyl)
4ag
a Reaction was performed with (Z)-2-benzylidene-1-arylbutane-1,3-
dione 3 (1.0 mmol), CuO (1.5 mmol), and I2 (1.2 mmol) in ethylene
glycol (5 mL) at 60 °C for 5 h. b Isolated yield.
c
—
a Reaction was performed with aryl methyl ketone 6 (1.0 mmol), CuO
(1.5 mmol), and I2 (1.2 mmol) in ethylene glycol (5 mL) at 60 °C for
5 h. b Isolated yield. c Only the α-iodoketone product was obtained in
92% yield.
Scheme 4 Control experiment.
1,3-propanediol as solvent. Unexpectedly, only the unprotected
iodinated product 5 was obtained in excellent yield (90%;
Scheme 4a).
Scheme 5 Proposed reaction mechanism.
To provide insight into the proposed mechanism, a control
experiment was then performed (Scheme 4). When α-iodo-
ketone 3aa was used as substrate in ethylene glycol, the
desired product 4aa was obtained in 92% yield in the presence
of iodine (Scheme 4b). However, no desired product 4aa was
obtained without iodine. This result clearly confirmed our sus-
picion that I2 could efficiently catalyze the ketalization
reaction.18
To further extend the scope of this reaction, simple aryl
methyl ketones 6 were also used as substrates (Table 4). For
substrates with electron-neutral substituents (–H), a moderate
yield was obtained (36%; entry 1). To our delight, the haloge-
nated substrates were also compatible under this reaction con-
dition, and moderate yields were obtained (43–52%; entries
2–5). Gratifyingly, substrates with electron withdrawing groups
afforded good to excellent yields (72–98%; entries 6–8).
However, for substrates with electron donating groups (–OMe),
only the α-iodoketone product was obtained in high yield
(92%). This is because the electron donating substituents on
the aromatic rings would decrease the positive charge on the
carbonyl carbon, which would make the carbonyl group less
electrophilic and retard its acetal formation, whereas electron
withdrawing substituents would facilitate it.15
Based on the previous studies, a possible reaction mechan-
ism was shown in Scheme 5 using 3aa as an example: sub-
strate 3aa first undergoes copper(II) oxide-catalyzed iodination
to give intermediate B, which could be further activated by
excess or in situ regenerated iodine (from oxidation of HI
byproduct by CuO) to form hemiketal D. The hydroxyl group in
D is protonated leading to the oxonium ion intermediate E,
which accepts the second hydroxyl group of ethylene glycol to
afford the desired product 4aa. The regioselective ketalization
of (Z)-2-arylidene-1-arylbutane-1,3-diones 3 is probably due to
the conjugation effect of aromatic rings deactivates the adja-
cent carbonyl group towards acetalisation.15
Conclusions
In summary, we have developed a sustainable integration strat-
egy for the direct and efficient synthesis of α-iodoketals from
(Z)-2-arylidene-1-arylbutane-1,3-diones and aryl methyl
ketones via successive tandem catalysis of copper(II) oxide and
iodine in ethylene glycol. Noteworthy features of this method
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are mild reaction condition, ease of manipulation, short reac- stirred at 60 °C for 5 h. After the reaction completed, the
tion time and good yields.
mixture was diluted with water and treated with Na2S2O3 (5%
w/w, aq.). The mixture was then extracted with CH2Cl2 (3 ×
20 mL), the combined organic extracts were dried over Na2SO4
and concentrated under reduced pressure. The crude product
was purified by column chromatography on silica gel (eluent :
petroleum ether–EtOAc = 15 : 1) to afford a yellow solid 5
(339 mg, 90%).
Preparation of α-iodoketals of (Z)-2-arylidene-1-arylbutane-
1,3-dione (7a as an example). Acetophenone 6a (120 mg,
1.0 mmol), CuO (120 mg, 1.5 mmol), and iodine (305 mg,
1.2 mmol) were placed in a sealed tube. After addition of anhy-
drous 1,3-propanediol (5 mL), the mixture was stirred at 60 °C
for 5 h. After the reaction completed, the mixture was diluted
with water and treated with Na2S2O3 (5% w/w, aq.). The
mixture was then extracted with CH2Cl2 (3 × 20 mL), the com-
bined organic extracts were dried over Na2SO4 and concen-
trated under reduced pressure. The crude product was purified
by column chromatography on silica gel (eluent : petroleum
ether–EtOAc = 80 : 1) to afford a yellow solid 7a (104 mg, 36%).
Experimental section
1
General methods
All reagents were purchased from commercial suppliers and
used without further purification. IR spectra were recorded on
an infrared spectrometer as KBr pellets with absorption in
cm−1 1H spectra were recorded in CDCl3 on 400/600 MHz
.
NMR spectrometers and resonances (δ) are given in ppm rela-
tive to tetramethylsilane. Data are reported as follows: chemi-
cal shift, multiplicity (s = singlet, d = doublet, t = triplet, m =
multiplet, brs = broad singlet), coupling constants (Hz) and
integration. 13C spectra were recorded in CDCl3 on 100/
150 MHz spectrometers and resonances (δ) are given in ppm
relative to the center line of a triplet at 77.0 ppm of chloro-
form-d. HRMS were obtained on an Apex-Ultra MS equipped
with APCI or ESI source. Melting points were determined
using XT-4 apparatus and not corrected. The X-ray crystal-
structure determination of 3ba, 3ia and 4aa was obtained on a
Bruker SMART APEX CCD system. Column chromatography
was performed on silica gel (200–300 mesh).
3
Spectroscopic data
(Z)-2-Benzylidene-1-phenylbutane-1,3-dione
(3aa). Yield
86%; white solid; m.p. 92.8–93.5 °C; 1H NMR (CDCl3,
400 MHz): δ 7.92 (d, J = 7.6 Hz, 2H), 7.79 (s, 1H), 7.53 (t, J =
7.6 Hz, 1H), 7.41–7.38 (m, 2H), 7.35–7.33 (m, 2H), 7.28–7.20
2
General procedures
Preparation of (Z)-2-arylidene-1-arylbutane-1,3-dione (3aa as (m, 3H), 2.39 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 198.0,
an example). Piperidine (20 mL) was added dropwise to the 195.8, 141.1, 139.6, 135.9, 134.0, 132.8, 130.4, 130.2, 129.1,
stirred solution of acetic acid (25 mL) in ice bath. Benz- 128.9, 128.8, 27.2; IR (KBr): 1678, 1651, 1619, 1233, 1207 cm−1
;
aldehyde 1a (1.06 g, 10.0 mmol) and 1-phenylbutane-1,3-dione HRMS (APCI): m/z [M + H]+ calcd for C17H15O2: 251.1067;
2a (1.62 g, 10.0 mmol) were then added into the mixture solu- found: 251.1068.
tion and stirred at room temperature for overnight. After the
(Z)-2-(4-Methylbenzylidene)-1-phenylbutane-1,3-dione (3ba).
reaction completed, the mixture was diluted with water and Yield 82%; white solid; m.p. 72.5–74.2 °C; 1H NMR (CDCl3,
extracted with CH2Cl2 (3 × 200 mL), the combined organic 400 MHz): δ 7.94–7.91 (m, 2H), 7.76 (s, 1H), 7.55–7.51 (m, 1H),
extracts were washed with NaOH (5% w/w, aq.) and brine suc- 7.40 (t, J = 7.6 Hz, 2H), 7.24 (d, J = 8.0 Hz, 2H), 7.03 (d, J =
cessively, then dried with Na2SO4, and concentrated under 8.4 Hz, 2H), 2.38 (s, 3H), 2.25 (s, 3H); 13C NMR (CDCl3,
reduced pressure. The crude product was purified by column 100 MHz): δ 198.3, 195.9, 141.3, 141.1, 138.5, 136.0, 134.0,
chromatography on silica gel (eluent : petroleum ether– 130.4, 129.9, 129.5, 129.1, 128.9, 27.0, 21.3; IR (KBr): 1669,
EtOAc = 10 : 1) to afford a white solid 3aa (2.15 g, 86%).
Preparation of α-iodoketals of (Z)-2-arylidene-1-arylbutane- calcd for C18H17O2: 265.1223; found: 265.1224.
1646, 1601, 1246, 1234, 1210 cm−1; HRMS (APCI): m/z [M + H]+
1,3-dione (4aa as an example). (Z)-2-Benzylidene-1-phenyl-
(Z)-2-(4-Methoxybenzylidene)-1-phenylbutane-1,3-dione (3ca).
butane-1,3-dione 3aa (250 mg, 1.0 mmol), CuO (120 mg, Yield 80%; white solid; m.p. 70.6–72.1 °C; 1H NMR (CDCl3,
1.5 mmol), and iodine (305 mg, 1.2 mmol) were placed in a 400 MHz): δ 7.93 (d, J = 7.2 Hz, 2H), 7.74 (s, 1H), 7.53 (t, J =
sealed tube. After addition of anhydrous ethylene glycol 7.2 Hz, 1H), 7.40 (t, J = 7.2 Hz, 2H), 7.31–7.27 (m, 2H), 6.73 (d,
(5 mL), the mixture was stirred at 60 °C for 5 h. After the reac- J = 8.8 Hz, 2H), 3.72 (s, 3H), 2.37 (s, 3H); 13C NMR (CDCl3,
tion completed, the mixture was diluted with water and treated 100 MHz): δ 198.5, 195.8, 161.4, 141.0, 137.2, 136.0, 133.9,
with Na2S2O3 (5% w/w, aq.). The mixture was then extracted 132.4, 129.0, 128.8, 125.2, 114.3, 55.2, 26.9; IR (KBr): 1670,
with CH2Cl2 (3 × 20 mL), the combined organic extracts were 1645, 1601, 1513, 1178 cm−1; HRMS (APCI): m/z [M + H]+ calcd
dried over Na2SO4 and concentrated under reduced pressure. for C18H17O3: 281.1172; found: 281.1173.
The crude product was purified by column chromatography on
silica gel (eluent : petroleum ether–EtOAc = 20 : 1) to afford a Yield 88%; light yellow solid; m.p. 152.1–153.6 °C; 1H NMR
white solid 4aa (357 mg, 85%). (CDCl3, 400 MHz): δ 8.08–8.05 (m, 2H), 7.89 (d, J = 8.0 Hz, 2H),
(Z)-2-(4-Nitrobenzylidene)-1-phenylbutane-1,3-dione (3da).
Preparation of 5. (Z)-2-Benzylidene-1-phenylbutane-1,3- 7.82 (s, 1H), 7.60–7.56 (m, 1H), 7.50 (d, J = 8.8 Hz, 2H),
dione 3aa (250 mg, 1.0 mmol), CuO (120 mg, 1.5 mmol), and 7.45–7.41 (m, 2H), 2.41 (s, 3H); 13C NMR (CDCl3, 100 MHz):
iodine (305 mg, 1.2 mmol) were placed in a sealed tube. After δ 196.9, 195.1, 148.2, 142.7, 139.2, 137.7, 135.4, 134.7, 130.6,
addition of anhydrous 1,3-propanediol (5 mL), the mixture was 129.2, 129.1, 123.9, 27.5; IR (KBr): 1678, 1657, 1595, 1519,
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1347, 1231 cm−1; HRMS (APCI): m/z [M + H]+ calcd for 1601, 1267, 1238, 1219, 1202 cm−1; HRMS (APCI): m/z [M + H]+
C17H14NO4: 296.0917; found: 296.0917.
calcd for C15H13O2S: 257.0631; found: 257.0632.
(Z)-2-(Naphthalen-1-ylmethylene)-1-phenylbutane-1,3-dione
(Z)-2-Benzylidene-1-(p-tolyl)butane-1,3-dione
(3ab). Yield
(3ea). Yield 77%; yellow oil; 1H NMR (CDCl3, 400 MHz): δ 8.60 83%; white solid; m.p. 106.0–107.2 °C; 1H NMR (CDCl3,
(s, 1H), 8.10 (d, J = 8.4 Hz, 1H), 7.80–7.78 (m, 3H), 7.71 (d, J = 400 MHz): δ 7.82 (d, J = 8.0 Hz, 2H), 7.77 (s, 1H), 7.35 (d, J =
8.4 Hz, 1H), 7.63–7.59 (m, 1H), 7.54–7.50 (m, 1H), 7.40–7.35 7.6 Hz, 2H), 7.26–7.19 (m, 5H), 2.37 (s, 3H), 2.35 (s, 3H); 13C
(m, 2H), 7.24–7.19 (m, 3H), 2.48 (s, 3H); 13C NMR (CDCl3, NMR (CDCl3, 100 MHz): δ 197.5, 195.8, 145.1, 140.8, 139.7,
100 MHz): δ 197.4, 195.5, 141.4, 139.2, 136.1, 133.7, 133.3, 133.6, 132.8, 130.3, 130.2, 129.6, 129.2, 128.7, 27.2, 21.6; IR
131.4, 130.6, 130.4, 128.9, 128.8, 128.6, 127.9, 127.0, 126.4, (KBr): 1675, 1649, 1620, 1605, 1237, 1208, 1182 cm−1; HRMS
125.2, 123.7, 27.8; IR (KBr): 1679, 1658, 1595, 1231 cm−1
;
(APCI): m/z [M + H]+ calcd for C18H17O2: 265.1223; found:
HRMS (APCI): m/z [M + H]+ calcd for C21H17O2: 301.1223; 265.1224.
found: 301.1224.
(Z)-2-Benzylidene-1-(naphthalen-2-yl)butane-1,3-dione (3ac).
(Z)-2-(Naphthalen-2-ylmethylene)-1-phenylbutane-1,3-dione Yield 75%; yellow solid; m.p. 86.5–87.5 °C; 1H NMR (CDCl3,
(3fa). Yield 78%; light yellow solid; m.p. 98.7–99.4 °C; 1H 400 MHz): δ 8.37 (s, 1H), 8.07 (d, J = 8.4 Hz, 1H), 7.88–7.81 (m,
NMR (CDCl3, 400 MHz): δ 7.97–7.95 (m, 3H), 7.89 (s, 1H), 4H), 7.56 (t, J = 6.8 Hz, 1H), 7.48 (t, J = 6.8 Hz, 1H), 7.40–7.38
7.73–7.68 (m, 2H), 7.61 (d, J = 8.4 Hz, 1H), 7.51–7.35 (m, 6H), (m, 2H), 7.20–7.16 (m, 3H), 2.42 (s, 3H); 13C NMR (CDCl3,
2.43 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 198.2, 195.8, 100 MHz): δ 197.9, 195.8, 141.2, 139.6, 136.0, 133.4, 132.8,
141.2, 139.5, 136.1, 134.1, 133.8, 132.8, 131.9, 130.3, 132.5, 131.8, 130.5, 130.3, 129.7, 129.0, 128.9, 128.8, 127.7,
129.1, 128.9, 128.6, 128.5, 127.7, 127.5, 126.7, 125.9, 27.2; 126.8, 123.8, 27.3; IR (KBr): 1668, 1653, 1620, 1243, 1182 cm−1
IR (KBr): 1675, 1648, 1610, 1362, 1262, 1231, 1174 cm−1 HRMS (APCI): m/z [M + H]+ calcd for C21H17O2: 301.1223;
HRMS (APCI): m/z [M + H]+ calcd for C21H17O2: 301.1223; found: 301.1224.
found: 301.1224. (Z)-2-Benzylidene-1-(4-chlorophenyl)butane-1,3-dione (3ad).
;
;
1
(Z)-2-(4-Chlorobenzylidene)-1-phenylbutane-1,3-dione (3ga). Yield 83%; white solid; m.p. 1084.–111.0 °C; H NMR (CDCl3,
Yield 83%; white solid; m.p. 90.2–91.7 °C; 1H NMR (CDCl3, 400 MHz): δ 7.86–7.82 (m, 2H), 7.79 (s, 1H), 7.39–7.35 (m, 2H),
400 MHz): δ 7.90 (d, J = 7.6 Hz, 2H), 7.74 (s, 1H), 7.58–7.54 (m, 7.33–7.22 (m, 5H), 2.42 (s, 3H); 13C NMR (CDCl3, 100 MHz):
1H), 7.42 (t, J = 7.2 Hz, 2H), 7.29–7.27 (m, 2H), 7.20 (d, J = δ 196.7, 195.9, 141.6, 140.6, 139.1, 134.3, 132.6, 130.7, 130.4,
8.0 Hz, 2H), 2.39 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 197.7, 130.2, 129.3, 128.9, 27.1; IR (KBr): 1681, 1648, 1621, 1586,
195.5, 139.9, 139.5, 136.5, 135.7, 134.3, 131.4, 131.3, 129.1, 1230, 1208 cm−1; HRMS (APCI): m/z [M + H]+ calcd for
129.0, 27.2; IR (KBr): 1679, 1655, 1618, 1230, 1210, 1089 cm−1
;
C17H14ClO2: 285.0677; found: 285.0679.
(Z)-2-Benzylidene-1-(4-bromophenyl)butane-1,3-dione (3ae).
Yield 84%; white solid; m.p. 125.4–126.5 °C; H NMR (CDCl3,
HRMS (APCI): m/z [M + H]+ calcd for C17H14ClO2: 285.0677;
1
found: 285.0679.
(Z)-2-(4-Bromobenzylidene)-1-phenylbutane-1,3-dione (3ha). 400 MHz): δ 7.79–7.75 (m, 3H), 7.54 (d, J = 8.4 Hz, 2H),
Yield 84%; white solid; m.p. 88.0–89.4 °C; 1H NMR (CDCl3, 7.33–7.23 (m, 5H), 2.42 (s, 3H); 13C NMR (CDCl3, 100 MHz):
400 MHz): δ 7.90 (d, J = 8.0 Hz, 2H), 7.71 (s, 1H), 7.54 (t, J = δ 196.9, 195.9, 141.6, 139.1, 134.7, 132.5, 132.2, 130.7, 130.5,
7.6 Hz, 1H), 7.41 (t, J = 7.6 Hz, 2H), 7.35–7.33 (m, 2H), 7.20 (d, 130.2, 129.4, 128.9, 27.0; IR (KBr): 1680, 1647, 1622, 1583,
J = 8.4 Hz, 2H), 2.38 (s, 3H); 13C NMR (CDCl3, 100 MHz): 1230, 1209 cm−1; HRMS (APCI): m/z [M + H]+ calcd for
δ 197.6, 195.5, 140.0, 139.5, 135.6, 134.2, 131.9, 131.6, 131.4, C17H14BrO2: 329.0172; found: 329.0173.
129.0, 128.9, 124.9, 27.1; IR (KBr): 1673, 1653, 1616, 1583,
1238 cm−1; HRMS (APCI): m/z [M + H]+ calcd for C17H14BrO2: 60%; white solid; m.p. 118.5–119.6 °C; 1H NMR (CDCl3,
329.0172; found: 329.0173. 400 MHz): δ 7.79 (s, 1H), 7.56 (brs, 1H), 7.39–7.37 (m, 2H),
(Z)-2-Benzylidene-1-(furan-2-yl)butane-1,3-dione (3af). Yield
(Z)-2-(4-Fluorobenzylidene)-1-phenylbutane-1,3-dione (3ia). 7.33–7.25 (m, 3H), 7.06 (d, J = 3.6 Hz, 1H), 6.45–6.43 (m, 1H),
Yield 80%; light yellow solid; m.p. 110.6–111.8 °C; 1H NMR 2.42 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 195.3, 184.6, 152.2,
(CDCl3, 400 MHz): δ 7.92–7.90 (m, 2H), 7.76 (s, 1H), 7.56 (t, J = 147.9, 142.1, 138.5, 132.8, 130.5, 130.1, 128.8, 120.4, 112.6,
7.6 Hz, 1H), 7.42 (t, J = 7.6 Hz, 2H), 7.36–7.33 (m, 2H), 6.92 (t, 27.2; IR (KBr): 1665, 1646, 1617, 1242 cm−1; HRMS (APCI): m/z
J = 8.4 Hz, 2H), 2.38 (s, 3H); 13C NMR (CDCl3, 100 MHz): [M + H]+ calcd for C15H13O3: 241.0859; found: 241.0860.
δ 198.0, 195.6, 165.0, 162.5, 139.8, 139.27, 139.25, 135.8, 134.3,
(Z)-2-Benzylidene-1-(thiophen-2-yl)butane-1,3-dione
(3ag).
132.4, 132.3, 129.1, 129.0, 116.2, 116.0, 27.3; IR (KBr): 1681, Yield 70%; white solid; m.p. 96.3–97.5 °C; 1H NMR (CDCl3,
1650, 1620, 1596, 1508, 1228, 1164 cm−1; HRMS (APCI): m/z 400 MHz): δ 7.79 (s, 1H), 7.66 (d, J = 4.0 Hz, 1H), 7.51 (d, J =
[M + H]+ calcd for C17H14FO2: 269.0972; found: 269.0974.
2.8 Hz, 1H), 7.43–7.41 (m, 2H), 7.32–7.24 (m, 3H), 7.01 (t, J =
(Z)-1-Phenyl-2-(thiophen-2-ylmethylene)butane-1,3-dione 4.4 Hz, 1H), 2.41 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 195.1,
(3ja). Yield 84%; white solid; m.p. 123.6–124.9 °C; 1H NMR 189.8, 143.6, 141.2, 139.2, 135.7, 134.7, 132.8, 130.6, 130.3,
(CDCl3, 400 MHz): δ 7.99–7.97 (m, 2H), 7.90 (s, 1H), 7.59 (t, J = 128.8, 128.5, 27.3; IR (KBr): 1660, 1638, 1615, 1413, 1246 cm−1
;
7.6 Hz, 1H), 7.45 (t, J = 7.6 Hz, 2H), 7.38 (d, J = 4.8 Hz, 1H), HRMS (APCI): m/z [M + H]+ calcd for C15H13O2S: 257.0631;
7.27–7.26 (m, 1H), 6.98–6.96 (m, 1H), 2.36 (s, 3H); 13C NMR found: 257.0633.
(CDCl3, 100 MHz): δ 197.7, 195.2, 136.5, 136.2, 135.9, 134.2,
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-1,3-diphenylprop-2-
133.2, 132.0, 129.2, 128.9, 128.0, 27.0; IR (KBr): 1670, 1647, en-1-one (4aa). Yield 85%; white solid; m.p. 135.5–136.4 °C;
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1H NMR (CDCl3, 400 MHz): δ 7.84–7.82 (m, 2H), 7.43 (t, J = 128.0, 127.4, 126.6, 126.3, 126.0, 107.3, 66.1, 13.3; IR (KBr):
7.6 Hz, 1H), 7.30 (t, J = 7.6 Hz, 2H), 7.21 (s, 1H), 7.19–7.12 (m, 1645, 1233, 1038 cm−1; HRMS (APCI): m/z [M + H]+ calcd for
5H), 4.19–4.16 (m, 2H), 4.04–4.01 (m, 2H), 3.88 (s, 2H); C23H20IO3: 471.0452; found: 471.0453.
13C NMR (CDCl3, 100 MHz): δ 197.7, 137.6, 135.9, 134.1, 133.4,
(E)-3-(4-Chlorophenyl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-1-
131.4, 129.2, 129.1, 128.6, 128.5, 128.4, 107.2, 66.1, 13.3; IR phenylprop-2-en-1-one (4ga). Yield 85%; white solid; m.p.
(KBr): 1650, 1238, 1036 cm−1; HRMS (APCI): m/z [M + H]+ calcd 123.7–124.6 °C; 1H NMR (CDCl3, 400 MHz): δ 7.83–7.81 (m,
for C19H18IO3: 421.0295; found: 421.0295.
2H), 7.47 (t, J = 7.2 Hz, 1H), 7.32 (t, J = 7.2 Hz, 2H), 7.15 (s,
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-1-phenyl-3-(p-tolyl)- 1H), 7.10 (brs, 4H), 4.19–4.16 (m, 2H), 4.03–4.00 (m, 2H), 3.85
prop-2-en-1-one (4ba). Yield 83%; white solid; m.p. (s, 2H); 13C NMR (CDCl3, 100 MHz): δ 197.5, 138.3, 135.7,
145.1–146.9 °C; 1H NMR (CDCl3, 400 MHz): δ 7.86–7.83 (m, 134.5, 133.7, 132.6, 130.3, 130.0, 129.1, 128.64, 128.60, 107.2,
2H), 7.44 (t, J = 7.2 Hz, 1H), 7.30 (t, J = 7.2 Hz, 2H), 7.16 (s, 66.1, 13.0; IR (KBr): 1649, 1237, 1038 cm−1; HRMS (APCI): m/z
1H), 7.07 (d, J = 8.0 Hz, 2H), 6.92 (d, J = 8.0 Hz, 2H), 4.17–4.14 [M + H]+ calcd for C19H17ClIO3: 454.9905; found: 454.9906.
(m, 2H), 4.02–3.99 (m, 2H), 3.87 (s, 2H), 2.19 (s, 3H); 13C NMR
(E)-3-(4-Bromophenyl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-1-
(CDCl3, 100 MHz): δ 197.9, 138.7, 136.4, 136.0, 133.3, 131.3, phenylprop-2-en-1-one (4ha). Yield 78%; white solid; m.p.
131.1, 129.1, 128.5, 107.2, 66.0, 21.1, 13.4; IR (KBr): 1648, 126.0–127.0 °C; 1H NMR (CDCl3, 400 MHz): δ 7.83–7.81 (m,
1237, 1038 cm−1; HRMS (APCI): m/z [M + H]+ calcd for 2H), 7.47 (t, J = 7.6 Hz, 1H), 7.32 (t, J = 7.6 Hz, 2H), 7.25 (d, J =
C20H20IO3: 435.0452; found: 435.0452.
8.4 Hz, 2H), 7.12 (s, 1H), 7.04 (d, J = 8.4 Hz, 2H), 4.19–4.15 (m,
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-(4-methoxyphenyl)- 2H), 4.03–4.00 (m, 2H), 3.85 (s, 2H); 13C NMR (CDCl3,
1-phenylprop-2-en-1-one (4ca). Yield 82%; white solid; m.p. 100 MHz): δ 197.4, 138.4, 135.7, 133.7, 133.0, 131.6, 130.5,
127.2–128.7 °C; 1H NMR (CDCl3, 400 MHz): δ 7.86–7.84 (m, 129.9, 129.1, 128.6, 122.8, 107.1, 66.1, 13.0; IR (KBr): 1648,
2H), 7.45 (t, J = 7.2 Hz, 1H), 7.31 (d, J = 7.2 Hz, 2H), 7.14–7.10 1236, 1038 cm−1; HRMS (APCI): m/z [M + H]+ calcd for
(m, 3H), 6.65 (d, J = 8.8 Hz, 2H), 4.17–4.14 (m, 2H), 4.02–3.99 C19H17BrIO3: 498.9400; found: 498.9402.
(m, 2H), 3.87 (s, 2H), 3.69 (s, 3H); 13C NMR (CDCl3, 100 MHz):
(E)-3-(4-Fluorophenyl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-1-
δ 198.1, 159.8, 136.0, 135.2, 133.4, 131.0, 130.7, 129.2, 128.5, phenylprop-2-en-1-one (4ia). Yield 73%; white solid; m.p.
126.6, 113.8, 107.2, 66.0, 55.1, 13.5; IR (KBr): 1643, 1608, 1511, 113.7–115.1 °C; 1H NMR (CDCl3, 400 MHz): δ 7.83–7.81 (m,
1261, 1178, 1032 cm−1; HRMS (APCI): m/z [M + H]+ calcd for 2H), 7.46 (t, J = 7.6 Hz, 1H), 7.31 (t, J = 7.6 Hz, 2H), 7.17–7.14
C20H20IO4: 451.0401; found: 451.0401.
(m, 3H), 6.81 (t, J = 8.8 Hz, 2H), 4.20–4.16 (m, 2H), 4.04–4.00
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-(4-nitrophenyl)-1- (m, 2H), 3.87 (s, 2H); 13C NMR (CDCl3, 100 MHz): δ 197.6,
phenylprop-2-en-1-one (4da). Yield 84%; white solid; m.p. 163.8, 161.3, 137.5, 135.8, 133.6, 130.9, 130.8, 130.3, 130.25,
163.7–164.5 °C; 1H NMR (CDCl3, 400 MHz): δ 7.99 (d, J = 130.2, 129.1, 128.5, 115.6, 115.4, 107.2, 66.1, 13.1; IR (KBr):
8.8 Hz, 2H), 7.81–7.79 (m, 2H), 7.48 (t, J = 7.6 Hz, 1H), 1657, 1597, 1505, 1234, 1035 cm−1; HRMS (APCI): m/z [M + H]+
7.35–7.31 (m, 4H), 7.25 (s, 1H), 4.23–4.19 (m, 2H), 4.07–4.03 calcd for C19H17FIO3: 439.0201; found: 439.0201.
(m, 2H), 3.85 (s, 2H); 13C NMR (CDCl3, 100 MHz): δ 196.8,
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-1-phenyl-3-(thiophen-
147.3, 142.0, 140.6, 135.5, 134.0, 129.6, 129.1, 128.82, 128.76, 2-yl)prop-2-en-1-one (4ja). Yield 89%; white solid; m.p.
123.7, 107.2, 66.3, 12.4; IR (KBr): 1656, 1594, 1515, 1342, 1234, 144.4–146.0 °C; 1H NMR (CDCl3, 400 MHz): δ 7.95–7.93 (m,
1034 cm−1; HRMS (APCI): m/z [M + H]+ calcd for C19H17INO5: 2H), 7.52 (d, J = 7.6 Hz, 1H), 7.39 (t, J = 7.6 Hz, 2H), 7.23 (s,
466.0146; found: 466.0146.
1H), 7.15 (d, J = 5.2 Hz, 1H), 6.94 (d, J = 3.6 Hz, 1H), 6.84–6.82
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-(naphthalen-1-yl)- (m, 1H), 4.18–4.14 (m, 2H), 4.04–4.01 (m, 2H), 3.81 (s, 2H); 13
C
1-phenylprop-2-en-1-one (4ea). Yield 60%; white solid; m.p. NMR (CDCl3, 100 MHz): δ 197.2, 137.0, 136.0, 135.7, 133.7,
131.3–132.4 °C; 1H NMR (CDCl3, 400 MHz): δ 8.05 (d, J = 129.9, 129.2, 128.7, 128.1, 127.3, 123.3, 106.9, 66.1, 13.1; IR
8.4 Hz, 1H), 7.95 (s, 1H), 7.73 (d, J = 8.0 Hz, 1H), 7.67–7.65 (m, (KBr): 1653, 1232, 1209, 1170, 1035 cm−1; HRMS (APCI): m/z
2H), 7.60–7.56 (m, 2H), 7.48 (t, J = 7.2 Hz, 1H), 7.25–7.16 (m, [M + H]+ calcd for C17H16IO3S: 426.9859; found: 426.9860.
2H), 7.11 (t, J = 7.2 Hz, 1H), 7.01 (t, J = 7.6 Hz, 2H), 4.29–4.23
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-phenyl-1-(p-tolyl)-
(m, 2H), 4.22–4.16 (m, 2H), 4.01 (s, 2H); 13C NMR (CDCl3, prop-2-en-1-one (4ab). Yield 82%; white solid; m.p.
1
100 MHz): δ 197.2, 139.5, 136.3, 133.2, 132.9, 131.6, 131.2, 92.6–94.2 °C; H NMR (CDCl3, 400 MHz): δ 7.74 (d, J = 8.0 Hz,
130.6, 129.0, 128.63, 128.58, 128.0, 127.6, 126.5, 126.0, 125.1, 2H), 7.20–7.17 (m, 3H), 7.13–7.08 (m, 5H), 4.18–4.14 (m, 2H),
123.8, 107.5, 66.2, 13.1; IR (KBr): 1658, 1230, 1176, 1036 cm−1
;
4.03–3.99 (m, 2H), 3.87 (s, 2H), 2.31 (s, 3H); 13C NMR (CDCl3,
HRMS (APCI): m/z [M + H]+ calcd for C23H20IO3: 471.0452; 100 MHz): δ 197.3, 144.3, 137.7, 134.1, 133.5, 131.0, 129.3,
found: 471.0452.
129.2, 129.1, 128.5, 128.4, 107.2, 66.0, 21.6, 13.4; IR (KBr):
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-(naphthalen-2-yl)-1- 1651, 1604, 1240, 1211, 1179, 1039 cm−1; HRMS (APCI): m/z [M
phenylprop-2-en-1-one (4fa). Yield 72%; white solid; m.p. + H]+ calcd for C20H20IO3: 435.0452; found: 435.0452.
120.1–122.0 °C; 1H NMR (CDCl3, 400 MHz): δ 7.88–7.86 (m,
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-1-(naphthalen-2-yl)-
2H), 7.69–7.65 (m, 3H), 7.55 (d, J = 8.4 Hz, 1H), 7.41–7.35 (m, 3-phenylprop-2-en-1-one (4ac). Yield 43%; white solid; m.p.
4H), 7.27–7.23 (m, 3H), 4.21–4.18 (m, 2H), 4.07–4.03 (m, 2H), 112.1–113.6 °C; 1H NMR (CDCl3, 400 MHz): δ 8.34 (s, 1H),
3.93 (s, 2H); 13C NMR (CDCl3, 100 MHz): δ 197.8, 137.7, 136.0, 7.95–7.93 (m, 1H), 7.82–7.76 (m, 3H), 7.56–7.52 (m, 1H),
133.4, 132.91, 132.87, 131.6, 131.4, 129.4, 129.0, 128.5, 128.1, 7.49–7.45 (m, 1H), 7.27–7.23 (m, 3H), 7.12–7.06 (m, 3H),
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4.20–4.16 (m, 2H), 4.07–4.04 (m, 2H), 3.91 (s, 2H); 13C NMR δ 139.1, 128.6, 128.3, 125.8, 106.7, 65.6, 14.0; IR (KBr): 1208,
(CDCl3, 100 MHz): δ 197.7, 137.8, 135.7, 134.1, 133.4, 132.4, 1159, 1035, 960, 703 cm−1; HRMS (ESI): m/z [M + H]+ calcd for
131.53, 131.49, 129.7, 129.1, 128.64, 128.60, 128.5, 127.7, C10H12IO2: 290.9876; found: 290.9877.
126.6, 124.3, 107.3, 66.2, 13.3; IR (KBr): 1653, 1626, 1218,
1184, 1033 cm−1; HRMS (APCI): m/z [M + H]+ calcd for 43%; yellow oil; 1H NMR (CDCl3, 600 MHz): δ 7.44 (d, J =
C23H20IO3: 471.0452; found: 471.0452. 8.4 Hz, 2H), 7.33 (d, J = 8.4 Hz, 2H), 4.20–4.18 (m, 2H),
2-(4-Chlorophenyl)-2-(iodomethyl)-1,3-dioxolane (7b). Yield
(E)-1-(4-Chlorophenyl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-3- 3.87–3.84 (m, 2H), 3.54 (s, 2H); 13C NMR (CDCl3, 150 MHz):
phenylprop-2-en-1-one (4ad). Yield 78%; white solid; m.p. δ 137.7, 134.6, 128.5, 127.4, 106.4, 65.7, 13.5; IR (KBr): 1487,
98.7–100.1 °C; 1H NMR (CDCl3, 400 MHz): δ 7.77–7.75 (m, 2H), 1208, 1091, 1040, 978, 832 cm−1; HRMS (ESI): m/z [M + H]+
7.27–7.25 (m, 2H), 7.23 (s, 1H), 7.15 (brs, 5H), 4.20–4.17 (m, calcd for C10H11ClIO2: 324.9487; found: 424.9488.
2H), 4.02–3.99 (m, 2H), 3.86 (s, 2H); 13C NMR (CDCl3,
2-(3,4-Dichlorophenyl)-2-(iodomethyl)-1,3-dioxolane
(7c).
100 MHz): δ 196.5, 139.8, 137.1, 134.3, 133.9, 131.7, 130.5, Yield 46%; yellow oil; 1H NMR (CDCl3, 400 MHz): δ 7.60 (d, J =
129.1, 128.84, 128.80, 128.5, 107.3, 66.1, 13.0; IR (KBr): 1658, 2.4 Hz, 1H), 7.33 (d, J = 8.4 Hz, 1H), 7.35–7.32 (m, 1H),
1228, 1040 cm−1; HRMS (APCI): m/z [M + H]+ calcd for 4.21–4.18 (m, 2H), 3.89–3.85 (m, 2H), 3.51 (s, 2H); 13C NMR
C19H17ClIO3: 454.9905; found: 454.9906.
(CDCl3, 100 MHz): δ 139.7, 132.6, 130.4, 128.1, 125.4, 106.0,
(E)-1-(4-Bromophenyl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-3- 65.9, 12.8; IR (KBr): 1467, 1378, 1208, 1167, 1033, 977 cm−1
;
phenylprop-2-en-1-one (4ae). Yield 73%; white solid; m.p. HRMS (ESI): m/z [M + H]+ calcd for C10H10Cl2IO2: 358.9097;
111.5–112.6 °C; 1H NMR (CDCl3, 400 MHz): δ 7.68 (d, J = found: 358.9099.
8.4 Hz, 2H), 7.43 (d, J = 8.4 Hz, 2H), 7.22 (s, 1H), 7.15 (brs, 5H),
2-(4-Bromophenyl)-2-(iodomethyl)-1,3-dioxolane (7d). Yield
4.20–4.17 (m, 2H), 4.02–3.99 (m, 2H), 3.86 (s, 2H); 13C NMR 52%; yellow solid; m.p. 56.2–58.3 °C; 1H NMR (CDCl3,
(CDCl3, 100 MHz): δ 196.7, 137.1, 134.7, 133.8, 131.8, 131.7, 400 MHz): δ 7.49 (d, J = 8.4 Hz, 2H), 7.38 (d, J = 8.4 Hz, 2H),
130.5, 129.0, 128.8, 128.7, 128.5, 107.2, 66.1, 13.0; IR (KBr): 4.20–4.17 (m, 2H), 3.87–3.84 (m, 2H), 3.53 (s, 2H); 13C NMR
1658, 1221, 1040 cm−1; HRMS (APCI): m/z [M + H]+ calcd for (CDCl3, 100 MHz): δ 138.3, 131.5, 127.7, 122.9, 106.5, 65.7,
C19H17BrIO3: 498.9400; found: 498.9402.
13.3; IR (KBr): 1584, 1479, 1405, 1208, 1039, 976, 956, 940,
(E)-1-(Furan-2-yl)-2-(2-(iodomethyl)-1,3-dioxolan-2-yl)-3-phe- 830 cm−1; HRMS (ESI): m/z [M + H]+ calcd for C10H11BrIO2:
nylprop-2-en-1-one (4af). Yield 85%; white solid; m.p. 368.8982; found: 368.8982.
1
137.6–139.2 °C; H NMR (CDCl3, 400 MHz): δ 7.434–7.428 (m,
2-(4-Fluorophenyl)-2-(iodomethyl)-1,3-dioxolane (7e). Yield
1H), 7.21–7.17 (m, 6H), 6.93 (d, J = 3.6 Hz, 1H), 6.34–6.33 (m, 44%; yellow oil; 1H NMR (CDCl3, 600 MHz): δ 7.49–7.47
1H), 4.21–4.17 (m, 2H), 4.07–4.04 (m, 2H), 3.88 (s, 2H); 13C (m, 2H), 7.05–7.02 (m, 2H), 4.20–4.19 (m, 2H), 3.87–3.85
NMR (CDCl3, 100 MHz): δ 184.6, 152.4, 147.1, 137.0, 134.2, (m, 2H), 3.55 (s, 2H); 13C NMR (CDCl3, 150 MHz): δ 163.6,
132.7, 128.8, 128.6, 128.4, 119.7, 112.3, 106.8, 66.0, 12.8; IR 162.0, 135.0, 127.8, 127.7, 115.2, 115.1, 106.4, 65.7, 13.8; IR
(KBr): 1641, 1624, 1040 cm−1; HRMS (APCI): m/z [M + H]+ calcd (KBr): 1602, 1504, 1225, 1158, 1040, 978, 840, 566 cm−1; HRMS
for C17H16IO4: 411.0088; found: 411.0087.
(E)-2-(2-(Iodomethyl)-1,3-dioxolan-2-yl)-3-phenyl-1-(thiophen- 308.9784.
2-yl)prop-2-en-1-one (4ag). Yield 88%; white solid; m.p. 2-(Iodomethyl)-2-(4-nitrophenyl)-1,3-dioxolane
(ESI): m/z [M + H]+ calcd for C10H11FIO2: 308.9782; found:
(7f). Yield
136.4–137.3 °C; 1H NMR (CDCl3, 400 MHz): δ 7.53–7.51 (m, 98%; white solid; m.p. 108.1–111.4 °C; 1H NMR (CDCl3,
1H), 7.45–7.44 (m, 1H), 7.26–7.23 (m, 2H), 7.19–7.16 (m, 4H), 400 MHz): δ 8.22 (d, J = 8.8 Hz, 2H), 7.70 (d, J = 8.8 Hz, 2H),
6.91–6.89 (m, 1H), 4.20–4.19 (m, 2H), 4.07–4.04 (m, 2H), 3.89 4.26–4.23 (m, 2H), 3.91–3.88 (m, 2H), 3.55 (s, 2H); 13C NMR
(s, 2H); 13C NMR (CDCl3, 100 MHz): δ 189.5, 143.8, 138.0, (CDCl3, 100 MHz): δ 148.1, 146.4, 127.1, 123.5, 106.3, 66.0,
134.7, 134.2, 133.9, 131.8, 129.1, 128.7 128.4, 128.1, 107.0, 12.3; IR (KBr): 1518, 1345, 1214, 1037, 855, 700 cm−1; HRMS
66.1, 13.0; IR (KBr): 1642, 1625, 1411, 1245, 1054 cm−1; HRMS (ESI): m/z [M + H]+ calcd for C10H11INO4: 335.9727; found:
(APCI): m/z [M + H]+ calcd for C17H16IO3S: 426.9859; found: 335.9723.
426.9860.
2-(Iodomethyl)-2-(3-nitrophenyl)-1,3-dioxolane
(7g). Yield
(E)-2-Benzylidene-4-iodo-1-phenylbutane-1,3-dione (5). Yield 84%; white solid; m.p. 83.0–84.1 °C; 1H NMR (CDCl3,
90%; yellow solid; m.p. 112.5–113.6 °C; 1H NMR (CDCl3, 400 MHz): δ 8.39–8.38 (m, 1H), 8.22–8.20 (m, 1H), 7.87–7.85
600 MHz): δ 7.98 (s, 1H), 7.95 (d, J = 7.2 Hz, 2H), 7.52 (t, J = (m, 1H), 7.57 (t, J = 8.0 Hz, 1H), 4.27–4.23 (m, 2H), 3.92–3.89
7.8 Hz, 1H), 7.39 (t, J = 7.8 Hz, 2H), 7.33 (d, J = 7.2 Hz, 2H), (m, 2H), 3.56 (s, 2H); 13C NMR (CDCl3, 100 MHz): δ 148.2,
7.29–7.26 (m, 1H), 7.22 (t, J = 7.2 Hz, 2H), 4.20 (s, 2H); 141.8, 132.1, 129.4, 123.7, 121.2, 106.2, 66.0, 12.5; IR (KBr):
13C NMR (CDCl3, 100 MHz): δ 196.8, 190.6, 143.6, 135.9, 135.8, 1524, 1347, 1213, 1045, 979, 690 cm−1; HRMS (ESI): m/z
134.1, 132.6, 130.8, 130.5, 129.4, 128.8, 128.7, 2.3; IR (KBr): [M + H]+ calcd for C10H11INO4: 335.9727; found: 335.9726.
1668, 1639, 1616, 1258, 1233, 1211 cm−1; HRMS (APCI): m/z
2-(Iodomethyl)-2-(2-nitrophenyl)-1,3-dioxolane (7h). Yield
72%; white solid; m.p. 108.3–110.5 °C; 1H NMR (CDCl3,
[M + H]+ calcd for C17H14IO2: 377.0033; found: 377.0034.
2-(Iodomethyl)-2-phenyl-1,3-dioxolane
(7a). Yield
36%; 400 MHz): δ 7.72 (d, J = 7.6 Hz, 1H), 7.57–7.47 (m, 3H),
yellow solid; m.p. 65.5–67.0 °C; 1H NMR (CDCl3, 400 MHz): 4.18–4.15 (m, 2H), 3.92 (s, 2H), 3.79–3.76 (m, 2H); 13C NMR
δ 7.51–7.49 (m, 2H), 7.38–7.33 (m, 3H), 4.20–4.17 (m, 2H), (CDCl3, 100 MHz): δ 149.6, 132.0, 131.2, 129.9, 129.0, 123.5,
3.88–3.84 (m, 2H), 3.58 (s, 2H); 13C NMR (CDCl3, 100 MHz): 105.7, 65.9, 12.5; IR (KBr): 1539, 1361, 1205, 1030, 976,
1232 | Org. Biomol. Chem., 2013, 11, 1226–1233
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786 cm−1; HRMS (ESI): m/z [M + H]+ calcd for C10H11INO4:
335.9727; found: 335.9727.
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We thank the National Natural Science Foundation of China
(Grant 20872042 and 21032001). We also thank Dr Chuanqi
Zhou for his help in performing HRMS analysis and Dr Xiang-
gao Meng for his help in performing X-ray diffraction analysis.
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