One-pot synthesis of new type aza- Baylis-Hillman adducts from chlorovinyl aldehydes under solvent-free condition

Article abstract of DOI:10.3184/030823410X12627215361201

A series of new type aza- Baylis-Hillman adducts were prepared in moderate yields by one-pot treatment of chlorovinyl aldehydes, benzenesulfonamides and activated olefi ns under solvent-free condition. The chlorovinyl aldehydes were obtained via chlorofor

Full text of DOI:10.3184/030823410X12627215361201

44 RESEARCH PAPER
JANUARY, 44–49
JOURNAL OF CHEMICAL RESEARCH 2010
One-pot synthesis of new type aza- Baylis–Hillman adducts from
chlorovinyl aldehydes under solvent-free condition
Weihui Zhong*, Yanhui Chen and Guan Wang
Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University
ofTechnology, Hangzhou 310014, P.R. China
A series of new type aza- Baylis–Hillman adducts were prepared in moderate yields by one-pot treatment of chloro-
vinyl aldehydes, benzenesulfonamides and activated olefins under solvent-free condition. The chlorovinyl aldehydes
were obtained via chloroformylation of ketones using bis(trichloromethyl)carbonate(BTC)/DMF system.
Keywords: aza- Baylis–Hillman reaction, chlorovinyl aldehydes, chloroformylation, benzenesulfonamides
The Baylis–Hillman reaction has become an important tool in
organic synthesis because of the formation of carbon–carbon
bonds under mild conditions.1–3 The aza version provides a
convenient method for the synthesis of α-methylene-β-amino
carbonyl compounds. The aza- Baylis–Hillman adducts
and their rearranged derivatives are used extensively for the
synthesis of many heterocyclic compounds which are key
skeletons in many biologically important compounds.2,4–9 To
improve the aza- Baylis–Hillman reaction, various methods
including Lewis acids catalysis,10–12 ultrasound13,14 or micro-
waves irradiation,15 using ionic liquids16,17 or supercritical
carbon dioxide18 as solvents, under high pressure19,20 have
proved advantageous in some cases.
In continuation of our research on Baylis–Hillman reaction
and its adducts,21–23 recently we have developed an efficient
synthesis of new type Baylis–Hillman adducts from the chlo-
rovinyl aldehydes which were prepared by treatment of ketones
with the Vilsmeier reagent derived from bis(trichloromethyl)
carbonate(BTC)/DMF system instead of the traditional POCl3/
DMF system24 (Scheme 1). Then, we suspected that new type
aza- Baylis–Hillman adducts might be synthesised in one pot
from the chlorovinyl aldehydes.
Initially, (Z)-3-chloro-3-phenylacrylaldehyde 1a was mixed
with toluenesulfonamide 2a and methyl acrylate 3a at room
temperature in DMF catalysed by DABCO (Table 1, entry 1),
however, no desired new aza- Baylis–Hillman adduct 4a was
detected but a new Baylis–Hillman adduct 5a was isolated
with 86%. When the Lewis acid AlCl3 was added to the above
reaction, 30% of 4a, accompanied with 8% of 5a and 23% of
chlorovinyl aldehyde 1a was isolated (Table 1, entry 2). Other
solvents such as toluene and THF gave also unsatisfactory
results. When this reaction was carried out under solvent-
free conditions at room temperature for 3 hours, the desired
product 4a was isolated with a yield of 58% (Table 1, entry 5).
Attempts to elevate or decrease reaction temperature and
prolong the reaction time under solvent-free conditions failed
to improve the product yield, but some of the starting material
1a was recovered (Table 1, entries 6–8). Compared to DABCO,
the base DMAP and DBU provided only traces of 4a and worse
results were observed using ZnCl2 or CF3CO2H as additives
instead of AlCl .
On the other3hand, to improve the reaction yield, we tried to
prepare 4a via formation of benzenesufonimide derivative 6a.
Firstly treatment of (Z)-3-chloro-3-phenylacrylaldehyde 1a
with toluenesulfonamide 2a catalysed by AlCl3 generated a
benzenesufonimide derivative 6a in situ, which was directly
used for Baylis–Hillman reaction by mixture with methyl
acrylate 3a in the presence of DABCO at room temperature for
48 h. To our disappointment, TLC showed that no reaction
took place and a mixture of the starting material 1a and
the intermediate 6a was isolated after column chromatography
on silica gel (Scheme 2). So, the optimal condition for the
preparation of 4 was to mix 1, 2 with 3 at room temperature
under solvent-free conditions catalysed by DABCO and AlCl3
system.
In order to extend the scope of this strategy, various chloro-
vinyl aldehydes 1, benzenesulfonamides 2 and activated
olefins 3 were used for aza- Baylis–Hillman reaction under
similar conditions and the full results are summarised in
Table 2. It was found that most of the substrates 1 gave the
corresponding aza- Baylis–Hillman adducts 4a–o in low to
moderate yields (30–60%).
According to Table 2, the electron-withdrawing groups on
the aromatic ring were found to benefit the formation of
aza- Baylis–Hillman adducts. Compared to methyl acrylate,
ethyl acrylate provided the corresponding products 4 with
lower yield over prolonged reaction times. To our surprise,
when but-3-en-2-one was used instead of methyl acrylate, only
Baylis–Hillman adducts 5n–o were formed quickly in high
yields (Table 2, entries 14–15), which is very different from
the previously reported results.25
In addition, other special substrates were also investigated
under the optimal condition. The substrate 1p could be
provided the desired product 4p and the side product 5p in
Scheme 1
* Correspondent. E-mail: pharmlab@zjut.edu.cn

JOURNAL OF CHEMICAL RESEARCH 2010 45
Table 1 The aza- Baylis–Hillman reactions of 1a under different conditionsa
Entry
Catalyst
Additives
Solvents
Temp./°C
Time/h
Yield/%b
4a
5a
1
2
DABCO
DABCO
DABCO
DABCO
DABCO
DABCO
DABCO
DABCO
DMAP
–
DMF
rt
rt
rt
rt
rt
rt
0
50
rt
rt
rt
rt
rt
14
14
14
14
3
14
14
3
–
86
8
AlCl
DMF
30c
35c
32c
58
3
AlCl3
AlCl3
AlCl3
AlCl3
AlCl3
AlCl3
AlCl3
AlCl3
AlCl33
ZnCl
CF3C2O2H
Toluene
THF
10
11
20
18
15
12
9
12
14
18
13
4
5
Solvent-free
Solvent-free
Solvent-free
Solvent-free
Solvent-free
Solvent-free
Solvent-free
Solvent-free
Solvent-free
6
56
7
48
8
50
9
48
48
48
8
TraceC
TraceC
TraceC
49
10
11
12
13
DBU
K CO3
D2ABCO
DABCO
36
34c
aConditions: 1a (3.0 mmol), 2a (3.0 mmol), 3a (9.0 mmol), additives (1.5 mmol), bases (0.6 mmol), solvents (10 mL) were used.
bIsolated yields based on 1a.
cSome chlorovinyl aldehyde 1a was recovered.
Scheme 2
Table 2 The synthesis of new type aza- Baylis–Hillman adductsa
Entry
Ar1
Ar2
EWG
Time/h
Product (Yield/%)b
4
5
1
2
C H
4-MeC6H4
Ph
2-ClC6H4
4-MeC H
4-MeC6H4
4-MeC66H44
Ph
4-MeC H
4-MeC6H4
4-MeC66H44
Ph
4-MeC H
4-MeC6H4
4-MeC6H4
4-MeC66H44
CO Me
CO2Me
CO2Me
CO2Et
10
24
72
72
1
4a (58)
4b (48)
4c (28c)
4d (36)
4e (47)
4f (33c)
4g (45)
4h (42)
4i(55)
5a (20)
5a (18)
5a (10)
5d (15)
5e(17)
5f (11)
5e(16)
5h (15)
5i (15)
5j (12)
5j (10)
5l (15)
5m (16)
5n (68)
5o (70)
C6H5
3
C6H5
4
C66H55
5
p-MeC H
p-MeC6H4
p-MeC66H44
p-FC6H4
p-ClC6H4
m-ClC H
m-ClC66H4
p-MeOC64H4
p-NO2C6H4
C6H5
CO2Me
CO2Et
6
72
24
1
7
CO2Me
CO2Me
CO2Me
CO2Me
CO2Me
CO2Me
CO2Me
CO2Me
COMe
8
9
2
10
11
12
13
14
15
10
12
2
4j (40c)
4k (30c)
4l (53)
1
0.5
0.5
4m (60)
4n (NDd)
4o (NDd)
p-FC6H4
aConditions: 1 (3.0 mmol), 2 (3.0 mmol), 3 (9.0 mmol), AlCl3 (1.5 mmol), DABCO (0.6 mmol) were used.
bIsolated yields based on 1.
cThe reaction was carried out under ultrasound and solvent-free conditions.
dNo desired products were detected.

46 JOURNAL OF CHEMICAL RESEARCH 2010
carried out on a Vario EL III instrument. The chlorovinyl aldehydes
were prepared by treatment of ketones with bis(trichloromethyl)carbo
nate (BTC)/DMF system.24
50% and 15%, respectively (Scheme 3). When (Z)-3-chloro-
2-methyl-3-phenylacrylaldehyde 1q derived from propiophe-
none was tested under similar conditions, 30% of the
aza- Baylis–Hillman adduct 4q, accompanied with the
unexpected 4-chloro-3-methyl-1-tosyl-1,2-dihydroquinoline
7 (50%) was obtained (Scheme 3). Further study showed that
the unique product 7 was formed in 85% when using just AlCl3
as catalyst. A plausible mechanism of this process includes
Friedel-Crafts acylation and ring enlargement as shown in
Scheme 4.
In summary, we have developed a one-pot synthesis of new
aza- Baylis–Hillman adducts from chlorovinyl aldehydes with
low to moderate yields. Further studies on their application are
now in progress in our laboratory.
Typical procedure for (Z)-methyl 5-chloro-2-methylene-3-(tolylsul-
fonamido)-5-phenylpent-4-enoate (4a) and (Z)-methyl 5-chloro-3-
hydroxy-2-methylene-5-phenylpent-4-enoate (5a)
To a mixture of (Z)-3-chloro-3-phenylacrylaldehyde 1a (3.0 mmol),
toluenesulfonamide 2a (3.0 mmol) and methyl acrylate 3a (9.0 mmol),
were added AlCl3 (1.5 mmol) and DABCO (0.6 mmol). The mixture
was stirred at room temperature for a given time (Table 2). Then the
reaction was quenched with water and extracted with dichloromethane
(30 mL×3). The combined organic layers were dried over Na2SO4 and
concentrated under vacuum and the obtained residue was further
purified by flash column chromatography on silica gel (petroleum
ether:ethyl acetate = 8:1) to give the desired product 4a and the side
product 5a.
Experimental
The products 4b–q and 5d–f, 5h–j, 5l–p could also be prepared
under the similar conditions.
Melting points were determined on a Büchi B-540 capillary melting
point apparatus and uncorrected. IR spectra were recorded on a
1
Thermo Nicolet Avatar 370 spectropho-tometer. H and 13C spectra
Typical procedure for 4-chloro-3-methyl-1-tosyl-1,2-dihydroquinoline
(7)
To a mixture of (Z)-3-chloro-2-methyl-3-phenylacrylaldehyde 1q
(3.0 mmol), toluenesulfonamide 2a (3.0 mmol) were added AlCl3
(1.5 mmol). The mixture was stirred at room temperature for 2h.
Then the reaction was quenched with water and extracted with
were recorded in CDCl with tetramethylsilane (TMS, δ = 0) as an
internal standard at amb3ient temperature on a Varian-400 MHz spec-
trometer at 400 and 100 MHz. Chemical shifts (δ) are expressed in
ppm and coupling constants J are given in Hz. Mass spectra were
obtained on a Trace DSQ mass spectrometer. Elemental analyses were
Scheme 3
Scheme 4 Plausible mechanism for the formation of 7.

JOURNAL OF CHEMICAL RESEARCH 2010 47
dichloromethane (30 mL × 3). The combined organic layers were
dried over Na SO and concentrated under vacuum and the obtained
residue was fu2rthe4r purified by flash column chromatography on silica
gel (petroleum ether:ethyl acetate = 8:1) to give the product 7.
(Z)-Methyl 5-chloro-2-methylene-3-(tolylsulfonamido)-5-phenyl-
pent-4-enoate (4a): Yellow solid; m.p. 112–114 °C. 1H NMR(CDCl3,
400MHz): δ 2.29 (3H, s, CH ), 3.71 (3H, s, CH3O), 5.24 (1H, t,
J = 8.8 Hz, CH), 5.83 (1H, d3, J = 10.0 Hz, C=CH), 5.93 (1H, s,
MeCO C=CH), 6.00 (1H, d, J = 8.4 Hz, NH), 6.17 (1H, s,
MeCO22C=CH), 7.18–7.74 (7H, m, ArH), 7.75 (2H, d, J = 8.0 Hz,
ArH); 13C NMR(CDCl3, 100M Hz): δ 21.4, 52.2, 56.3, 124.8, 126.4,
127.2, 128.1(2C), 128.4(2C), 129.1(2C), 129.5(2C), 134.9, 136.5,
136.6, 137.8, 143.5, 166.0; IR (KBr): 3252, 1709, 1634, 1589,
1164 cm−1; MS (ESI) 428[M+Na]+; Anal. Calcd for C H20ClNO4S: C,
59.18; H, 4.97; N, 3.45. Found: C, 59.29; H, 5.13; N,230 .51%.
J = 8.4 Hz, NH), 6.14 (1H, s, MeCO C=CH), 7.07 (2H, d, J = 8.4 Hz,
ArH), 7.16 (2H, d, J = 8.4 Hz, ArH)2, 7.40–7.47 (3H, m, ArH), 7.85–
7.87 (2H, m, ArH); 13C NMR(CDCl , 100MHz): δ 21.1, 29.7, 52.2,
56.4, 123.7, 126.4(2C), 127.1(2C),3 128.3(2C), 128.9(2C), 132.6,
133.9, 135.2, 136.6, 139.4, 140.9, 166.0; IR (neat): 3273, 1716, 1633,
1446, 1163 cm−1; MS (ESI) 440[M+Cl]–; Anal. Calcd for
C H ClNO4S: C, 59.18; H, 4.97; N, 3.45. Found: C, 59.25; H, 4.91;
N2,03.2209%.
(Z)-Methyl 5-chloro-5-(4-fluorophenyl)-2-methylene-3-(tolylsulfo-
namido)pent-4-enoate (4h): Yellow solid; m.p. 118–120 °C. 1H
NMR(CDCl3, 400MHz): δ 2.30 (3H, s, CH3), 3.71 (3H, s, CH3O), 5.22
(1H, t, J = 9.6 Hz, CH), 5.90 (2H, m, C=CH and MeCO2C=CH), 5.98
(1H, d, J = 9.6 Hz, NH), 6.16 (1H, s, MeCO2C=CH), 6.93–6.97 (2H,
m, ArH), 7.18–7.74 (4H, m, ArH), 7.75 (2H, d, J = 8.0 Hz, ArH); 13
C
NMR(CDCl3, 100MHz): δ 21.3, 52.1, 56.2, 114.7, 115.0, 124.8, 128.3
(2C), 128.4(2C), 129.4(2C), 132.9(2C), 133.8, 136.6, 137.9, 143.4,
163.1 (d, JCF 250.1 Hz), 165.9; IR (neat): 3255, 1708, 1633, 1597,
1164 cm−1; MS (ESI) 446[M+Na]+; Anal. Calcd for C20H ClFNO4S:
C, 56.67; H, 4.52; N, 3.30. Found: C, 56.58; H, 4.40; N, 31.942%.
(Z)-Methyl 5-chloro-5-(4-chlorophenyl)-2-methylene-3-(tolylsulfo-
namido)pent-4-enoate (4i): White solid; m.p. 108–110 °C. 1H
NMR(CDCl3, 400MHz): δ 2.31 (3H, s, CH3), 3.72 (3H, s, CH3O), 5.21
(1H, t, J = 8.8 Hz, CH), 5.77 (1H, d, J = 10.0 Hz, C=CH), 5.93 (1H,
s, MeCO2C=CH), 6.00 (1H, d, J = 8.4 Hz, NH), 6.17 (1H, s,
MeCO2C=CH), 7.18 (2H, d, J = 8.6 Hz, ArH), 7.22 (2H, d, J = 9.6 Hz,
ArH), 7.26 (2H, d, J = 2.4 Hz, ArH), 7.73 (2H, d, J = 8.0 Hz, ArH);
13C NMR(CDCl3, 100MHz): δ 21.4, 52.2, 56.4, 125.4, 127.2,
127.7(2C), 128.3(2C), 128.6(2C), 129.5(2C), 133.8, 135.1, 135.1,
136.4, 137.9, 143.5, 166.0; IR (KBr): 3259, 1708, 1634, 1486,
1162 cm−1; MS (ESI) 474[M+Cl]–; Anal. Calcd for C H19Cl2NO4S: C,
54.55; H, 4.35; N, 3.18. Found: C, 54.59; H, 4.45, N2,03.29%.
(Z)-Methyl 5-chloro-5-(3-chlorophenyl)-2-methylene-3-(tolylsulfo-
namido)pent-4-enoate (4j): Yellow oil. 1H NMR(CDCl3, 400MHz): δ
2.32 (3H, s, CH3), 3.74 (3H, s, CH3O), 5.21 (1H, t, J = 8.4 Hz, CH),
5.76 (1H, d, J = 10.0 Hz, C=CH), 5.96 (1H, s, MeCO C=CH), 5.98
(1H, d, J = 8.4 Hz, NH), 6.19 (1H, s, MeCO2C=CH),2 7.12 (2H, d,
J = 7.2 Hz, ArH), 7.18 (2H, d, J = 16.8 Hz, ArH), 7.22 (2H, d,
J = 8.0 Hz, ArH), 7.74 (2H, d, J = 8.4 Hz, ArH); 13C NMR(CDCl3,
100MHz): δ 21.4, 52.3, 56.4, 124.7, 126.1, 126.5, 127.2, 128.7(2C),
129.1(2C), 129.4, 129.6, 130.5, 133.4, 136.3, 138.5, 139.7, 143.7,
166.0; IR (neat): 3280, 1707, 1593, 1503, 1160 cm−1; MS (ESI)
474[M+Cl]–; Anal. Calcd for C20H19Cl NO4S: C, 54.55; H, 4.35; N,
3.18. Found: C, 54.65; H, 4.21; N, 3.322%.
(Z)-Methyl 5-chloro-5-(3-chlorophenyl)-2-methylene-3-(phenylsul-
fonamido)pent-4-enoate (4k):Yellow oil. 1H NMR(CDCl3, 400MHz):
δ 3.73 (3H, s, CH3O), 5.24 (1H, t, J = 9.6 Hz, CH), 5.85 (1H, d,
J = 9.6 Hz, C=CH), 5.94 (1H, s, MeCO C=CH), 6.04 (1H, d,
J = 8.4 Hz, NH), 6.17 (1H, s, MeCO2C=CH),27.15–7.29 (4H, m, ArH),
7.43–7.51 (3H, m, ArH), 7.87 (2H, d, J = 6.8 Hz, ArH); 13C
NMR(CDCl , 100MHz): δ 52.3, 56.3, 124.7, 125.9, 126.6, 127.1,
128.8, 129.03(2C), 129.2, 129.5(2C), 132.7, 133.6, 134.2, 136.2, 138.3,
140.8, 165.7; IR (neat): 3256, 1711, 1629, 1425, 1164 cm−1; MS (ESI)
460[M+Cl]–; Anal. Calcd for C19H17Cl NO4S: C, 53.53; H, 4.02; N,
3.29. Found: C, 53.45; H, 3.94; N, 3.372%.
(Z)-Methyl 5-chloro-5-(4-methoxyphenyl)-2-methylene-3-(tolylsul-
fonamido)pent-4-enoate (4l): White solid; m.p. 101–103 °C. 1H
NMR(CDCl3, 400MHz): δ 2.31 (3H, s, CH3), 3.71 (3H, s, CH3O), 3.80
(3H, s, CH3O), 5.22 (1H, t, J = 9.2 Hz, CH), 5.77 (1H, d, J = 9.6 Hz,
C=CH), 5.87 (1H, s, MeCO C=CH), 5.91 (1H, d, J = 10.0 Hz, NH),
6.15 (1H, s, MeCO2C=CH), 26.78 (2H, d, J = 8.8 Hz, ArH), 7.16–7.27
(4H, m, ArH), 7.74 (2H, d, J = 8.4 Hz, ArH); 13C NMR(CDCl3,
100MHz): δ 21.4, 29.7, 52.1, 55.3, 56.4, 113.4, 122.9, 127.2(2C),
127.8(2C), 128.2(2C), 129.5(2C), 134.7, 136.7, 137.9, 143.4, 160.2,
166.0; IR (KBr): 3250, 1708, 1633, 1508, 1164 cm−1; MS (ESI)
470[M+Cl]–; Anal. Calcd for C21H22ClNO5S: C, 57.86; H, 5.09; N,
3.21. Found: C, 57.99; H, 5.19; N, 3.29%.
(Z)-Methyl 5-chloro-2-methylene-5-phenyl-3-(phenylsulfonamido)
1
pent-4-enoate (4b): Yellow oil. H NMR(CDCl3, 400MHz): δ 3.71
(3H, s, CH3O), 5.27 (1H, m, CH), 5.83 (1H, d, J = 10.0 Hz, C=CH),
5.93 (1H, s, MeCO2C=CH), 6.05 (1H, d, J = 8.8 Hz, NH), 6.15 (1H, s,
MeCO2C=CH), 7.27–7.49 (7H, m, ArH), 7.87 (2H, m, ArH); 13C
NMR(CDCl3, 100MHz): δ 52.2, 56.3, 124.6, 126.5, 127.1, 128.2(2C),
128.5(2C), 128.9(2C),129.2(2C), 132.6, 135.1, 136.5, 136.7, 140.8,
165.9; IR (neat): 3280, 1715, 1578, 1446, 1164 cm−1; MS (ESI)
390[M-1]–; Anal. Calcd for C H ClNO4S: C, 58.23; H, 4.63; N, 3.57.
Found: C, 58.34; H, 4.53; N, 139.3118%.
(Z)-Methyl 5-chloro-3-(2-chlorophenylsulfonamido)-2-methylene-
5-phenylpent-4-enoate (4c):Yellow oil. 1H NMR(CDCl3, 400MHz): δ
3.76 (3H, s, CH3O), 5.25 (1H, m, CH), 5.86 (1H, s, MeCO C=CH),
6.14 (1H, s, MeCO2C=CH), 6.18 (1H, d, J = 8.8 Hz, C=C2H), 6.42
(1H, d, J = 10.0 Hz, NH), 7.24–7.43 (8H, m, ArH), 7.75 (1H, m, ArH);
13C NMR(CDCl3, 100MHz): δ 52.3, 56.6, 123.6, 126.4, 127.2, 128.2,
128.4, 129.2(2C), 130.1(2C), 131.2, 133.6(2C), 135.1, 136.3, 136.5,
138.1, 165.9; IR (neat): 3321, 1712, 1586, 1444, 1166 cm−1; MS (ESI)
460[M+Cl]–; Anal. Calcd for C19H17Cl NO4S: C, 53.53; H, 4.02; N,
3.29. Found: C, 53.43; H, 4.11; N, 3.372%.
(Z)-Ethyl 5-chloro-2-methylene-3-(tolylsulfonamido)-5-phenylpent-
4-enoate (4d): Light yellow solid; m.p. 113–115 °C. 1H NMR(CDCl ,
400MHz): δ 1.27 (3H, t, J = 9.2 Hz, CH3), 2.29 (3H, s, CH3), 4.137
(1H, d, J = 9.2 Hz, CH2O), 4.17 (1H, d, J = 9.2 Hz, CH2O), 5.23 (1H,
t, J = 9.2 Hz, CH), 5.78 (1H, d, J = 10.0 Hz, C=CH), 5.93 (1H,
s, MeCO2C=CH), 6.00 (1H, d, J = 8.4 Hz, NH), 6.16 (1H, s,
MeCO2C=CH), 7.19–7.30 (7H, m, ArH), 7.74 (2H, d, J = 8.0 Hz,
ArH); 13C NMR(CDCl3, 100MHz): δ 14.3, 21.7, 30.0, 56.7, 61.6,
125.2, 126.7, 127.5(2C), 128.5(2C), 129.4(2C), 129.8(2C), 135.2,
137.0, 137.1, 138.2, 143.7, 165.9; IR (neat): 3411, 1715, 1634, 1441,
1160 cm−1; MS (ESI) 418[M-1]–; Anal. Calcd for C21H22ClNO4S: C,
60.06; H, 5.28; N, 3.34. Found: C, 59.93; H, 5.21; N, 3.45%.
(Z)-Methyl 5-chloro-2-methylene-3-(tolylsulfonamido)-5-tolylpent-
4-enoate (4e): Yellow solid; m.p. 105–106 °C. 1H NMR(CDCl3,
400MHz): δ 2.31 (6H, t, CH3), 3.71 (3H, s, CH3O), 5.23 (1H,
t, J = 8.8 Hz, CH), 5.77 (1H, d, J = 9.6 Hz, C=CH), 5.92 (1H, s,
MeCO C=CH), 5.94 (1H, d, J = 8.2 Hz, NH), 6.15 (1H, s,
MeCO22C=CH), 7.07 (2H, d, ArH), 7.13 (2H, d, J = 8.4 Hz, ArH), 7.20
(2H, d, J = 8.0 Hz, ArH), 7.73 (2H, d, J = 8.0 Hz, ArH); 13C
NMR(CDCl3, 100MHz): δ 21.2, 21.4, 52.1, 56.3, 123.8, 126.4,
127.2(2C), 128.3(2C), 128.8(2C), 129.5(2C), 133.9, 135.1, 136.7,
137.9, 139.2, 143.4, 166.0; IR (KBr): 3256, 1691, 1630, 1335,
1164 cm−1; MS (ESI) 418[M-1]–; Anal. Calcd for C21H22ClNO4S: C,
60.06; H, 5.28; N, 3.34. Found: C, 60.19; H, 5.45; N, 3.42%.
(Z)-Ethyl 5-chloro-2-methylene-3-(tolylsulfonamido)-5-tolylpent-
1
4-enoate (4f): Yellow oil. H NMR(CDCl3, 400MHz): δ 1.25–1.29
(3H, m, CH3), 2.31 (6H, d, J = 8.8 Hz, CH ), 4.11–4.20 (2H, m,
CH2O), 5.22 (1H, t, J = 9.2 Hz, CH), 5.77 (1H,3s, C=CH), 5.91 (1H, s,
MeCO C=CH), 5.95 (1H, d, J = 8.4 Hz, NH), 6.15 (1H, s,
MeCO22C=CH), 7.07 (2H, d, J = 8.4 Hz, ArH), 7.13 (2H, d, J = 4.4 Hz,
ArH), 7.19 (2H, d, J = 8.0 Hz, ArH), 7.73 (2H, d, J = 8.0 Hz, ArH);
13C NMR(CDCl3, 100MHz): δ 14.0, 21.1, 21.4, 56.4, 61.2, 123.9,
126.3(2C), 127.2(2C), 128.0, 128.8(2C), 129.5(2C), 134.0, 135.0,
137.0, 138.0, 139.2, 143.3, 165.6; IR (neat): 3260, 1690, 1625, 1439,
1161 cm−1; MS (ESI) 456[M+Na]+; Anal. Calcd for C H24ClNO4S: C,
60.89; H, 5.57; N, 3.23. Found: C, 60.96; H, 5.49; N,232 .19%.
(Z)-Methyl 5-chloro-2-methylene-3-(tolylsulfonamido)-5-(4-nitro-
phenyl)pent-4-enoate (4m): Yellow solid; m.p. 106–108 °C. 1H
NMR(CDCl3, 400MHz): δ 2.42 (3H, s, CH3), 3.71 (3H, s, CH3O), 4.61
(1H, t, J = 9.6 Hz, CH), 5.42 (1H, s, MeCO2C=CH), 5.65 (1H, d,
J = 9.2 Hz, C=CH), 6.03 (1H, s, MeCO2C=CH), 6.16 (1H, d, J =
10.4 Hz, NH), 7.21–7.26 (2H, m, ArH), 7.45 (2H, d, J = 9.2 Hz, ArH),
7.48–7.58 (2H, m, ArH), 8.22–8.24 (2H, m, ArH); 13C NMR(CDCl3,
100MHz): δ 21.5, 29.3, 56.4, 120.2, 123.5, 123.8(2C), 127.2(2C),
128.6(2C), 129.5(2C), 132.8, 137.1, 137.5, 142.0, 143.7, 148.1, 165.4;
(Z)-Methyl 5-chloro-2-methylene-3-(phenylsulfonamido)-5-tolyl-
1
pent-4-enoate (4g): Yellow oil. H NMR(CDCl3, 400MHz): δ 2.33
(3H, s, CH ), 3.71 (3H, s, CH3O), 5.25 (1H, t, J = 9.6 Hz, CH), 5.80
(1H, d, J =39.6 Hz, C=CH), 5.91 (1H, s, MeCO2C=CH), 6.00 (1H, d,

48 JOURNAL OF CHEMICAL RESEARCH 2010
IR (KBr): 3253, 1709, 1629, 1593, 1164 cm−1; MS (ESI) 449[M-1]–;
Anal. Calcd for C20H19ClN O6S: C, 53.28; H, 4.25; N, 6.21. Found: C,
53.43; H, 4.13; N, 6.29%. 2
270(M+, 3), 203(100);Anal. Calcd for C13H12ClFO3: C, 57.68; H, 4.47.
Found: C, 57.77; H, 4.39%.
(Z)-Methyl 5-chloro-5-(4-chlorophenyl)-3-hydroxy-2-methylene-
pent-4-enoate (5i): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 3.37
(1H, br s, OH), 3.81 (3H, s, CO2CH3), 5.45 (1H, d, J = 7.6 Hz, CHOH),
5.94 (1H, s, C = CH2-b), 6.30 (1H, s, C = CH2-a), 6.35 (1H, d,
J = 7.6 Hz, ClC = CH) 7.31–7.33 (2H, m, ArH), 7.51–7.53 (2H, m,
ArH); 13C NMR (100 MHz, CDCl3): δ 52.1, 70.4, 126.8, 127.7, 127.8
(2C), 128.5 (2C), 133.6, 135.1, 135.6, 139.3, 166.7; IR (neat): 3463,
2953, 1723, 1507, 1237 cm−1; MS (EI) m/z 286(M+, 1), 219(100);
Anal. Calcd for C13H12Cl2O3: C, 54.38; H, 4.21. Found: C, 54.45; H,
4.31%.
(Z)-Methyl 5-chloro-5-(3-chlorophenyl)-3-hydroxy-2-methylene-
pent-4-enoate (5j): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 3.82
(3H, s, CO2CH3), 5.44 (1H, d, J = 7.6 Hz, CHOH), 5.95 (1H, s,
C = CH2-b), 6.31 (1H, s, C = CH2-a), 6.38 (1H, d, J = 7.6 Hz,
ClC = CH), 7.29–7.31 (2H, m, ArH), 7.46–7.49 (1H, m, ArH), 7.58
(1H, s, ArH); 13C NMR (100 MHz, CDCl3): δ 52.1, 70.4, 124.7, 126.7,
126.9, 128.4, 129.1, 129.6, 133.3, 134.4, 138.8, 139.2, 166.7; IR
(neat):3435, 2952, 1720, 1440, 1335, 1156 cm−1; MS (EI) m/z 286(M+,
3), 251(100); Anal. Calcd for C13H12Cl2O3: C, 54.38; H, 4.21. Found:
C, 54.47; H, 4.18%.
(Z)-Methyl 5-chloro-3-hydroxy-5-(4-methoxyphenyl)-2-methylene-
pent-4-enoate (5l): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 3.45
(1H, br s, OH), 3.80 (6H, s, CO2CH3 and OCH3), 5.47 (1H, d,
J = 8.0 Hz, CHOH), 5.94 (1H, s, C = CH2-b), 6.24 (1H, d, J = 8.0 Hz,
ClC = CH), 6.28 (1H, s, C = CH2-a), 6.86 (2H, d, J = 8.8 Hz, ArH),
7.52 (2H, d, J = 8.4 Hz, ArH); 13C NMR (100 MHz, CDCl3): δ 52.0,
55.2, 70.2, 113.6 (2C), 125.2, 126.4, 127.9 (2C), 129.6, 134.5, 139.7,
160.2, 166.8; IR(neat): 3479, 2953, 1715, 1509, 1255, 1178 cm−1; MS
(EI) m/z 282(M+, 9), 215(100); Anal. Calcd for C14H15ClO4: C, 59.48;
H, 5.35. Found: C, 59.33; H, 5.26%.
(Z)-Methyl 5-chloro-3-hydroxy-2-methylene-5-(4-nitrophenyl)pent-
4-enoate (5m): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 3.46 (1H,
br s, OH), 3.83 (3H, s, CO2CH3), 5.47 (1H, d, J = 8.0 Hz, CHOH),
5.99 (1H, s, C = CH2-b), 6.34 (1H, s, C = CH2-a), 6.56 (1H, d,
J = 8.0 Hz, ClC = CH), 7.77 (2H, d, J = 8.8 Hz, ArH), 8.21 (2H, d,
J = 9.2 Hz, ArH); 13C NMR (100 MHz, CDCl3): δ 52.5, 70.8, 123.9
(2C), 127.5, 127.6 (2C), 131.5, 132.6, 139.3, 143.2, 148.2, 166.9; IR
(neat): 3480, 3106, 1703, 1518 cm−1; MS (EI) m/z 297(M+, 12),
1667(100); Anal. Calcd for C13H12ClNO5: C, 52.45; H, 4.06; N, 4.71.
Found: C, 52.53; H, 3.96; N, 4.72%.
Methyl 2-((1-chloro-3,4-dihydronaphthalen-2-yl)(tolylsulfonamido
)methyl)acrylate(4p):Yellowsolid;m.p. 130–133 °C.1HNMR(CDCl ,
400MHz): δ 2.21 (2H, t, J = 8.0 Hz, CH ), 2.29 (3H, s, CH3), 2.443–
2.59 (2H, m, CH2), 3.67 (3H, s, CH3O), 52.64 (1H, d, J = 8.8 Hz, CH),
5.93 (1H, s, MeCO2C=CH), 6.10 (1H, s, NH), 6.26 (1H, s,
MeCO2C=CH), 7.02 (1H, d, J = 7.2 Hz, ArH), 7.14–7.26 (4H, m,
ArH), 7.53 (1H, d, J = 7.6 Hz, ArH), 7.77 (2H, t, J = 6.8 Hz, ArH); 13C
NMR(CDCl , 100MHz): δ 21.4, 24.8, 27.3, 52.1, 56.4, 124.7, 126.5,
126.7, 127.23, 128.1(2C), 128.3, 128.8, 129.4(2C), 132.4, 132.4, 135.9,
136.8, 137.0, 143.5, 166.1; IR (KBr): 3264, 1727, 1629, 1589,
1154 cm−1; MS (ESI) 454[M+Na]+; Anal. Calcd for C H22ClNO4S: C,
61.18; H, 5.13; N, 3.24. Found: C, 61.22; H, 5.19; N,232 .29%.
(Z)-Methyl 5-chloro-4-methyl-2-methylene-3-(tolylsulfonamido)-5-
phenylpent-4-enoate (4q): Yellow solid; m.p. 122–124 °C.1H
NMR(CDCl3, 400MHz): δ 1.85 (3H, s, CH3), 2.40 (3H, s, CH ), 3.61
(3H, s, CH O), 5.03 (1H, d, J = 8.4 Hz, MeCO2C=CH), 5.29 3(1H, d,
J = 8.4 Hz,3MeCO C=CH), 5.58–5.70 (1H, m, NH), 6.06 (1H, s, CH),
7.19–7.34 (7H, m,2ArH and MeCO2C=CH), 7.55 (2H, d, J = 8.4 Hz,
ArH); 13C NMR(CDCl3, 100MHz): δ 15.9, 21.5, 52.1, 56.6, 127.2,
128.2, 128.5, 128.7(2C), 128.8(2C), 129.4(2C), 131.1(2C), 132.1,
137.2, 137.5, 137.9, 143.4, 166.1; IR (neat): 3215, 1708, 1580, 1437,
1163 cm−1; MS (ESI) 418[M-1]–; Anal. Calcd for C21H22ClNO4S: C,
60.06; H, 5.28; N, 3.34. Found: C, 60.17; H, 5.42; N, 3.44%.
(Z)-Methyl5-chloro-3-hydroxy-2-methylene-5-phenylpent-4-enoate
(5a):Yellow oil24. 1H NMR (CDCl3, 400 MHz): δ 3.44 (1H, br s, OH),
3.79 (3H, s, CO2CH ), 5.48 (1H, d, J = 7.6 Hz, CHOH), 5.94 (1H, s,
C = CH2-b), 6.29 (31H, s, C = CH2-a), 6.35 (1H, d, J = 7.6 Hz,
ClC = CH), 7.33–7.37 (3H, m, ArH), δ 7.57–7.60 (2H, m, ArH); 13C
NMR (CDCl3, 100 MHz): δ 52.070.2, 120.1, 126.5(2C), 127.2,
128.3(2C), 129.0, 134.7, 137.1,139.5, 166.7; IR (neat): 3466, 2954,
1724, 1507, 1238, 1161 cm−1; MS (EI) m/z 252 (M+, 3), 217 (81),
185(100); Anal. Calcd for C13H13ClO3: C, 61.79; H, 5.19. Found: C,
61.67; H, 5.12%.
(Z)-Ethyl 5-chloro-3-hydroxy-2-methylene-5-phenylpent-4-enoate
(5d): Yellow oil24. 1H NMR (CDCl , 400 MHz): δ 1.33 (3H, t,
J = 7.2 Hz, CO2CH2CH3), 3.34 (1H, br3s, OH), 4.26 (2H, q, J = 7.2 Hz,
CO2CH CH3), 5.47 (1H, d, J = 7.6 Hz, CHOH),5.93 (1H, s, C =
CH2-b),26.30 (1H, s, C = CH2-a),6.35 (1H, d, J = 7.6 Hz, ClC = CH),
7.33–7.39 (3H, m, ArH),δ 7.59–7.61 (2H, m, ArH); 13C NMR (CDCl3,
100 MHz): δ 14.1, 61.1, 70.5, 126.3, 126.6 (2C), 127.3, 128.3 (2C),
129.1, 134.8, 137.2, 139.7, 166.4 ; IR (neat): 3500, 2983, 1720, 1328,
1266 cm−1; MS (EI) m/z 266(M+, 4), 231(65), 185(100); Anal. Calcd
for C14H15ClO3: C, 63.04; H, 5.67. Found: C, 63.11; H, 5.62%.
(Z)-Methyl5-chloro-3-hydroxy-2-methylene-5-p-tolylpent-4-enoate
(5e): Yellow oil24. 1H NMR (CDCl3, 400 MHz): δ 2.35 (3H, s, CH3),
3.36 (1H, br s, OH), 3.80 (3H, s, CO2CH3), 5.47 (1H, d, J = 8.0 Hz,
CHOH), 5.94 (1H, s, C = CH -b), 6.29 (1H, s, C = CH2-a), 6.31 (1H,
d, J = 8.0 Hz, ClC = CH), 7.125 (2H, d, J = 8.4 Hz, ArH), 7.49 (2H, d,
J = 8.4 Hz, ArH); 13C NMR (CDCl , 100 MHz): δ 21.1, 52.1, 70.4,
126.2, 126.5(2C), 126.6, 129.0(2C),3134.4, 135.0, 139.2, 139.5,166.9;
IR (neat): 3478, 2982, 1716, 1260, 1177 cm−1; MS (EI) m/z 266(M+,
1), 231(51), 199(100); Anal. Calcd for C14H15ClO3: C, 63.04; H, 5.67.
Found: C, 62.98; H, 5.59%.
(Z)-6-Chloro-4-hydroxy-3-methylene-6-phenylhex-5-en-2-one(5n):
1
Yellow oil24. H NMR(CDCl3, 400MHz): δ 2.40 (3H, s, CH3), 5.44
(1H, d, J = 7.6 Hz, CH), 6.14(1H, s, MeCO2C=CH), 6.17(1H, s,
C=CH), 6.37(1H, d, J = 7.6 Hz, MeCO2C=CH), 7.26–7.38(3H, m,
ArH), 7.58–7.61 (2H, m, ArH); 13C NMR(CDCl3, 100MHz): δ 26.4,
71.0, 126.5(2C), 127.5, 127.6, 128.3(2C), 129.1, 134.4, 137.0, 147.0,
201.3; IR (neat): 3434, 1714, 1667, 1608 cm−1; MS (ESI) 271[M+Cl]–
; Anal. Calcd for C13H13ClO2: C, 65.97; H, 5.54. Found: C, 66.02; H,
5.43%.
(Z)-6-Chloro-6-(4-fluorophenyl)-4-hydroxy-3-methylenehex-5-en-
1
2-one (5o): Yellow oil24. H NMR(CDCl3, 400MHz): δ 2.40 (3H, s,
CH3), 5.41 (1H, d, J = 8.0 Hz, CH), 6.13 (1H, s, MeCO2C=CH), 6.18
(1H, s, C=CH), 6.30 (1H, d, J = 7.6 Hz, MeCO2C=CH), 7.02–7.06
(2H, m, ArH), 7.55–7.58 (2H, m, ArH); 13C NMR(CDCl3, 100MHz):
δ 26.4, 71.0, 115.2, 115.4(2C), 127.5, 127.6(2C), 128.5, 133.3, 147.0,
163.1 (d, JCF = 240.2 Hz), 201.2; IR (neat): 3280, 1704, 1589,
1505 cm−1; MS (ESI) 289[M+Cl]–; Anal. Calcd for C13H12ClFO2: C,
61.31; H, 4.75. Found: C, 61.39; H, 4.65%.
Methyl 2-((1-chloro-3,4-dihydronaphthalen-2-yl)(hydroxy)methyl)
acrylate (5p): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 2.27–2.33
(1H, m, CH2-b), 2.51–2.59 (1H, m, CH2-a), 2.77–2.82 (2H, m, CH2),
2.93 (1H, br s, OH), 3.76 (3H, s, CO2CH3), 5.89 (1H, s, CHOH), 5.94
(1H, s, C = CH2-b), 6.35 (1H, s, C = CH2-a), 7.12 (1H, d, J = 6.8 Hz,
ArH), 7.18–7.25 (2H, m, ArH), 7.64 (1H, d, J = 7.6 Hz, ArH); 13C
NMR (100 MHz, CDCl3): δ 23.5, 27.8, 52.0, 70.2, 124.7, 126.3, 126.6,
127.0, 128.0, 128.2, 132.7, 135.0, 136.3, 139.0, 166.8; IR (neat):
3478, 2952, 1727, 1438, 1270, 1146 cm−1;MS (EI) m/z 278(M+, 4),
165(100); Anal. Calcd for C15H15ClO3: C, 64.64; H, 5.42. Found: C,
64.71; H, 5.36%.
(Z)-Ethyl 5-chloro-3-hydroxy-2-methylene-5-p-tolylpent-4-enoate
(5f): Yellow oil24. 1H NMR (400 MHz, CDCl3): δ 1.32 (3H, t,
J = 7.2 Hz, CO2CH2CH3), 2.35 (3H, s, CH3), 3.39 (1H, br s, OH) δ,
4.25 (2H, q, J = 7.2 Hz, CO2CH2CH ), 5.47 (1H, d, J = 7.6 Hz,
CHOH), 5.92 (1H, s, C = CH -b), 6.29 3(1H, s, C = CH2-a), 6.30 (1H,
d, J = 8.0 Hz, ClC = CH), 7.125 (2H, d, J = 8.0 Hz, ArH), 7.48 (2H, d,
J = 8.0 Hz, ArH); 13C NMR (100 MHz, CDCl3): δ 14.3, 21.4, 61.4,
70.6, 126.5, 126.6 126.7 (2C), 129.3 (2C), 134.7, 135.1, 139.4, 140.2,
166.7; IR (neat): 3501, 3127, 1703, 1400, 1300, 1188 cm−1; MS (EI)
m/z 280(M+, 2), 245(63), 199(100); Anal. Calcd for C15H17ClO3: C,
64.17; H, 6.10. Found: C, 64.08; H, 6.19.
(Z)-Methyl 5-chloro-5-(4-fluorophenyl)-3-hydroxy-2-methylene-
pent-4-enoate (5h): Yellow oil24. 1H NMR (400 MHz, CDCl ): δ 3.38
(1H, br s, OH), 3.81 (3H, s, CO2CH3), 5.45 (1H, d, J = 7.6 Hz,3CHOH),
5.95 (1H, s, C = CH2-b), 6.30 (1H, s, C = CH -a), 6.31 (1H, d,
J = 8.0 Hz, ClC = CH), 7.02–7.06 (2H, m, ArH), 27.55–7.59 (2H, m,
ArH); 13C NMR (100 MHz, CDCl3): δ 52.1, 70.4, 115.2, 115.4, 126.7,
127.2, 128.4, 128.5, 133.3, 133.7, 139.5 163.1 (d, JCF = 247.9 Hz),
166.8; IR (neat): 3466, 2954, 1724, 1507, 1238 cm−1; MS (EI) m/z
4-Chloro-3-methyl-1-tosyl-1,2-dihydroquinoline (7): Yellow solid;
m.p. 192–195 °C. 1H NMR(CDCl3, 400MHz): δ 1.89 (3H, s, CH3),
2.48 (3H, s, CH3), 4.61 (1H, d, J = 9.6 Hz, CH2), 5.78 (1H, d,

JOURNAL OF CHEMICAL RESEARCH 2010 49
8
9
S. Gowrisankar, K.Y. Lee, T.H. Kim and J.N. Kim, Tetrahedron Lett., 2006,
47, 5785.
M.J. Lee, S.C. Kim and J.N. Kim, Bull. Korean Chem. Soc., 2006, 27,
439.
J = 10.0 Hz, CH2), 6.81 (1H, d, J = 7.2 Hz, ArH), 7.04–7.08 (1H, m,
ArH), 7.20–7.29 (2H, m, ArH), 7.37 (2H, d, J = 8.0 Hz, ArH), 7.86
(2H, d, J = 8.4 Hz, ArH); 13C NMR(CDCl3, 100MHz): δ 11.2, 21.5,
61.0, 118.6, 123.2, 126.4, 127.2, 128.7(2C), 129.3, 129.9(2C), 138.3,
138.4, 140.7, 141.2, 143.8; IR(KBr): 3444, 1625, 1405, 1327,
1164 cm−1; MS(ESI) 368[M+Cl]–; Anal. Calcd for C17H16ClNO2S: C,
61.16; H, 4.83; N, 4.20. Found: C, 61.27; H, 4.75; N, 4.17%.
10 V.K. Aggarwal, G.J. Tarver and R. McCague, Chem. Commun., 1996,
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11 V.K. Aggarwal, D.K. Dean, A. Mereu and R. Williams, J. Org. Chem.,
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12 H.S. Kim, H.S. Lee and J.N. Kim, Bull. Korean Chem. Soc., 2009, 30,
941
We thank the National Key Technology R&D Program [No:
2007BAI34B01] and the Opening Foundation of Zhejiang
Provincial Top Key Pharmaceutical Discipline for financial
support.
13 F. Coelho, W.P. Almeida, D. Veronese, C.R. Mateus, E.C.S. Lopes, R.C.
Rossi, G.P.C. Silveira and C.H. Pavam, Tetrahedron, 2002, 58, 7437.
14 W.P. Almeida and F. Coelho, Tetrahedron Lett., 1998, 39, 8609.
15 M.K. Kundu, S.B. Mukherjee, N. Balu, R. Padmakumar and S.V. Bhat,
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16 N. Jain, A. Kumar, S. Chauhan and S.M.S. Chauhan, Tetrahedron, 2005,
Received 21 October 2009; accepted 28 December 2009
Paper 090832 doi: 10.3184/030823410X12627215361201
Published online: 22 January 2010
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17 J.N. Rosa, C.A.M. Afonso and A.G. Santos, Tetrahedron, 2001, 57, 4189.
18 P.M. Rose, A.A. Clifford and C.M. Rayner, Chem. Commun., 2002,
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22 W.H. Zhong, Y.Z. Zhao, B.M. Guo, P. Wu and W.K. Su, Synth. Commun.,
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23 W.H. Zhong, Y.Z. Zhao and W.K. Su, Tetrahedron, 2008, 64, 5491.
24 W.H. Zhong, L.B. Jiang, B.M. Guo, Y.T. Wu, L.J. Hong and Y.H. Chen,
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