Synthetic access to new carbamate and thiocarbamate derivatives from pyridinecarbaldehyde oximes and hydroxypyridines

Article abstract of DOI:10.1080/00397911.2010.490627

The synthesis of pyridine carbamate and thiocarbamate derivates is described. A series of oxime carbamate and thiocarbamate derivatives were synthesized by the addition of 2-, 3-, and 4-pyridinecarbaldehyde oximes to isocyanates and isothiocyanates. Furth

Full text of DOI:10.1080/00397911.2010.490627

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Synthetic Access to New Carbamate
and Thiocarbamate Derivatives from
Pyridinecarbaldehyde Oximes and
Hydroxypyridines
Ahmet Kocak a , Gulnare Ahmetli b , Nuriye Kocak c , Sait Malkondu a
, Aysegul Yaylaci a & Sultan Kurbanli a
a Department of Chemistry , Faculty of Science, Selcuk University ,
Konya , Turkey
b Department of Chemical Engineering , Faculty of Engineering and
Architecture, Selcuk University , Konya , Turkey
c Department of Science Education , Faculty of Education, Selcuk
University , Konya , Turkey
Published online: 20 Apr 2011.
To cite this article: Ahmet Kocak , Gulnare Ahmetli , Nuriye Kocak , Sait Malkondu , Aysegul Yaylaci
& Sultan Kurbanli (2011) Synthetic Access to New Carbamate and Thiocarbamate Derivatives from
Pyridinecarbaldehyde Oximes and Hydroxypyridines, Synthetic Communications: An International
Journal for Rapid Communication of Synthetic Organic Chemistry, 41:11, 1629-1637, DOI:
10.1080/00397911.2010.490627
To link to this article: http://dx.doi.org/10.1080/00397911.2010.490627
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Synthetic Communications1, 41: 1629–1637, 2011
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397911.2010.490627
SYNTHETIC ACCESS TO NEW CARBAMATE AND
THIOCARBAMATE DERIVATIVES FROM
PYRIDINECARBALDEHYDE OXIMES AND
HYDROXYPYRIDINES
Ahmet Kocak,1 Gulnare Ahmetli,2 Nuriye Kocak,3
Sait Malkondu,1 Aysegul Yaylaci,1 and Sultan Kurbanli1
1Department of Chemistry, Faculty of Science, Selcuk University, Konya,
Turkey
2Department of Chemical Engineering, Faculty of Engineering and
Architecture, Selcuk University, Konya, Turkey
3Department of Science Education, Faculty of Education, Selcuk University,
Konya, Turkey
GRAPHICAL ABSTRACT
Abstract The synthesis of pyridine carbamate and thiocarbamate derivates is described. A
series of oxime carbamate and thiocarbamate derivatives were synthesized by the addition
of 2-, 3-, and 4-pyridinecarbaldehyde oximes to isocyanates and isothiocyanates. Further-
more, carbamate and thiocarbamate derivatives of pyridine were synthesized by the addition
of 2-, 3-, and 4-hydroxy pyridine to isocyanates and isothiocyanates. Their structures were
confirmed by both analytical and spectral data.
Keywords Addition; carbamate; carbamoyl oxime; thiocarbamate
INTRODUCTION
Carbamates (urethanes) are of particular interest because of their usefulness
in various industries,[1–3] such as agrochemicals,[1,2,4,5] where they are used as
herbicides, fungicides, and pesticides, and in pharmaceuticals[1,2,6] as drug inter-
mediates. Moreover, they can be used as an isocyanate source[7] for the synthesis
of polyuretanes and polyureas. In addition to these, among the various
Received February 23, 2010.
Address correspondence to Sultan Kurbanli, Department of Chemistry, Faculty of Science, Selcuk
University, 42075 Konya, Turkey. E-mail: skurbanli@gmail.com
1629

1630
A. KOCAK ET AL.
amine-protecting groups, carbamates are commonly used because of their chemical
stability to acids, bases, and hydrogenation.[8]
They are usually prepared by addition of an amine to a chloroformate[9] or
alternately by addition of a hydroxy compound to an N-substituted carbamoyl
chloride.[10] The pyridine ring system occurs in the structures of many natural pro-
ducts and pharmaceutical and agrochemical compounds.[11] We report herein the
synthesis of a series of carbamate and thiocarbamate derivatives containing the
pyridine ring system.
RESULTS AND DISCUSSION
In our previous studies, O-alkylation reaction of pyridine carbaldehyde oximes
with dihalohydrins under phase-transfer conditions has been investigated,[12] and a
series of pyridone derivatives has been synthesized by the reaction of hydroxy pyr-
idines with various oxiranes.[13] As a continuation of our investigations, we report
the synthesis of a series of carbamate and thiocarbamate derivatives of pyridine
(Schemes 1 and 2).
The best solvents described in the literature[14–17] for this reaction, such as tolu-
ene–dimethylsulfoxide (DMSO) or tolene–dimethylformamide (DMF) mixtures,
have a strong donor capacity and a good ability to establish hydrogen bonds. It is
preferable to perform the reactions in solvents inert to the reactants [e.g., in diethyl
ether, dioxane, tetrahydrofuran (THF), and acetonitrile]. Triethylamine was used
because it has good catalytic strength.[18] The combined effect of solvent and catalyst
cannot be easily predicted, as the relevant physicochemical properties of the solvent
have not yet been reported.[15] The optimal conditions for oxime derivatization with
phenylisocyanate are the use of acetonitrile or dichlorometane as solvents and the
presence of triethylamine at room temperature.
Aryl isocyanates are more reactive than alkyl isocyanates.[18–20] The use of a
phenyl isocyanate instead of an alkyl or allyl isocyanate enhances carbamate forma-
tion. The results agree with the observations of Duggan[19] concerning the relative
reactivity of the phenyl isocyanate and benzyl isocyanates. The derivatization took
place at temperature range of 30–50 ꢀC to avoid the decomposition of the formed
carbamates, which are generally hydrolysable.[21] The product carbamates or thio-
carbamates can be recovered from the product mixture using conventional techni-
ques such as distillation, recrystallization, filtration, and the like.
Scheme 1. Synthesis of pyridine carbamoyl and thiocarbamoyl oximes.

OXIME CARBAMATES AND THIOCARBAMATES
1631
Scheme 2. Synthesis of pyridine carbamates and thiocarbamates.
Addition of pyridine carbaldehyde oximes to isocyanates and isothiocyanates
proceeds regiospecifically to afford the corresponding carbamoyl and thiocarbamoyl
oxime derivatives (1–8) in moderate yields. The prepared pyridinecarbaldehyde
oximes and the corresponding products (1–8) were identified as possessing the E
configuration by correlation of 1H NMR spectra. In these compounds, the chemical
shift (d 8.30–8.57) of the imine proton is downfield of the aromatic protons. If they
possess the Z configuration, the imine proton would resonate upfield of the aromatic
compounds.[22]
The structures of the carbamates and thiocarbamates were confirmed on both
analytical and spectral data. The elemental analysis results agree with the theoretical
values (Table 1). The Fourier transform–infrared (FT-IR) spectra of carbamates
exhibited N-H stretching in the region of 3195–3220 cmꢁ1. The carbamate deriva-
=
tives (1–6 and 9–12) showed strong C O stretching absorptions in the region of
1700–1720 cmꢁ1, and thiocarbamate derivates (7, 8 and 13, 14) showed the presence
of weak C S stretching absorptions in the region of 1275–1295 cmꢁ1. The carbamoyl
=
Table 1. Physical data of the newly synthesized compounds
Elemental analysis calc. (found)
Mp (ꢀC) or
Compound Yield (%) bp (ꢀC=mmHg)
C
H
N
S
1
2
75
61
69
52
48
54
42
44
75
78
55
50
44
48
133–135
130
64.72 (64.54) 4.60 (4.48) 17.42 (17.18)
64.72 (64.52) 4.60 (4.45) 17.42 (17.04)
64.72 (64.46) 4.60 (4.52) 17.42 (17.05)
55.96 (55.82) 5.74 (5.64) 21.74 (21.85)
58.54 (58.36) 5.37 (5.28) 15.61 (15.52)
58.54 (58.40) 5.37 (5.22) 15.61 (15.48)
—
—
—
—
—
—
3
120–122
88–89
4
5
140–142
192–194
Oil
6
7
54.28 (54.12) 5.01 (4.86) 18.99 (18.76) 14.49 (14.38)
54.28 (54.05) 5.01 (4.92) 18.99 (18.72) 14.49 (14.32)
8
Oil
9
126–127
130–131a
112–113
118–119
121–122 (1.5)
138–140 (0.5)
67.82 (67.42) 4.71 (4.68) 13.08 (13.12)
67.82 (67.56) 4.71 (4.60) 13.08 (12.92)
60.66 (60.42) 5.66 (5.54) 15.72 (15.64)
60.66 (60.38) 5.66 (5.44) 15.72 (15.52)
—
—
—
—
10
11
12
13
14
55.67 (55.54) 5.15 (5.08) 14.32 (14.18) 16.49 (16.36)
55.67 (55.48) 5.15 (5.04) 14.32 (14.12) 16.49 (16.42)
[23]
.
aLit. 132 ꢀC

1632
A. KOCAK ET AL.
Figure 1. Numbering employed in NMR assignments.
=
and thiocarbamoyl oxime derivatives (1–8) exhibited strong C N stretching bands in
the region of 1660–1685 cmꢁ1
The numbering scheme employed in NMR assignments is presented in Fig. 1.
.
1
In the H NMR spectra, chemical shifts, integrations, and splitting of products
are consistent with the predicted values. In carbamoyl and thiocarbamoyl oxime
derivatives (1–8), NH protons were observed in the region d 6.56–6.94. These pro-
tons in compounds 9–14 were observed in the region d 6.42–6.67. NH protons in
compounds 9–14 were shifted upfield because of the lack of electron-withdrawing
oxime function. The imine protons in compounds 1–8 were observed as singlets
in the region d 8.30–8.57. In the 13C NMR spectra of 1–6 and 9–12, carbonyl
=
carbon (C O) resonated in the region d 164.9–168.8, whereas in compounds 7, 8,
=
13, and 14, thiocarbonyl carbon (C S) resonated downfield in the region d
181.4–184.7.
EXPERIMENTAL
All chemicals were purchased from Merck and Aldrich and were used without
additional purification. Other commercial-grade solvents were distilled and then
stored over molecular sieves. The melting points were determined on a Buchi capil-
lary melting-point apparatus. The FT-IR spectra were recorded on a Pye Unicam SP
1
1025 spectrometer. The H NMR and 13C NMR spectra were recorded from solu-
tions in CDCl3 on a Bruker Avance DPX 400 instrument using tetramethylsilane
(TMS) as reference. The elemental compositions were determined on a Carlo Erba
1106 automatic CHN analyzer. Analytical thin-layer chromatography (TLC) was
performed on Merck 60 Kieselgel F254 silica-gel plates; spots were visualized under
ultra violet light.
Synthesis of Oximes (General Procedure)
A mixture of hydroxylamine hydrochloride (3.47 g, 0.05 mol) and Na2CO3
(5.3 g, 0.05 mol) in 50 mL of benzene were stirred at 60 ꢀC for 45 min. Then 2-, 3-,
or 4-pyridinecarbaldehyde (5.36 g, 0.05 mol) was added dropwise, and stirring was
continued at 80 ꢀC for 4–5 h. After completion of the reaction, the organic layer
was separated from the salt by filtration and neutralized with acetic acid (2 N).
The organic layer was separated and dried over MgSO4. The solvent was removed
under reduced pressure. The residue was dissolved in methanol or dichloromethane
(DCM). The product was precipitated with petroleum ether. The precipitate was fil-
tered, dried, and used in further reactions without purification.

OXIME CARBAMATES AND THIOCARBAMATES
1633
Synthesis of Oxime Carbamates with Phenyl Isocyanate 1–3
A solution of phenylisocyanate (1.19 g, 0.01 mol) in DCM (10 mL) was added
to a solution of (E)-2-, 3-, or 4-pyridinecarbaldehyde oxime (1.22 g, 0.01 mol) and
triethylamine (1.0 mL, 0.01 mol) in DCM (25 mL). The mixture was stirred at
30 ꢀC for 2–3 h. The course of the reaction was occasionally monitored by TLC.
After completion of the reaction, the product was filtered and washed with water.
The product was recrystallized from a mixture of methanol and CCl4. Spectral data
of 1–3 are presented.
Selected Data for 1–3
(E)-2-Pyridinecarbaldehyde-N-phenylcarbamoyl oxime 1. IR spectrum,
1
max, cmꢁ1: 3215 (N-H), 1705 (C O), 1670 (C N), 965 (N-O). H NMR spectrum,
=
=
t
=
d, ppm: 8.86 (1H, dd, H6, J ¼ 4.9, 1.8 Hz), 8.57 (1H, s, CH N), 7.94 (1H, dt, H4,
0
0
J ¼ 7.7, 1.8 Hz), 7.78 (1H, dd, H3, J ¼ 8.1, 1.6 Hz), 7.52 (2H, dd, H2 ,6 , J ¼ 7.8,
0
0
1.4 Hz), 7.40 (1H, dt, H5, J ¼ 7.7, 4.9 Hz), 7.32 (2H, dt, H3 ,5 , J ¼ 7.8, 1.4 Hz), 7.11
(1H, dt, H4 , J ¼ 7.5, 1.6 Hz), 6.92 (1H, s, NH). 13C NMR spectrum, d, ppm: 168.8
0
0
=
=
(C O), 152.5 (C-2), 150.3 (C-6), 149.8 (CH N), 138.3 (C-1 ), 136.7 (C-4), 129.5
(C-30,50), 125.3 (C-40), 124.0 (C-5), 120.2 (C-20,60), 119.8 (C-3).
(E)-3-Pyridinecarbaldehyde-N-phenylcarbamoyl oxime 2. IR spectrum,
1
max, cmꢁ1: 3195 (N-H), 1715 (C O), 1685 (C N), 960 (N-O). H NMR spectrum,
=
=
t
d, ppm: 8.92 (1H, t, H2, J ¼ 1.2 Hz), 8.70 (1H, dd, H6, J ¼ 4.7, 1.6 Hz), 8.30 (1H, s,
=
CH N), 8.15 (1H, td, H4, J ¼ 7.7, 1.6 Hz), 7.56 (1H, dd, H5, J ¼ 7.7, 4.7 Hz), 7.48
13
0
0
0
0
(2H, dd, H2 ,6 , J ¼ 7.7, 1.5 Hz), 7.30 (2H, dt, H3 ,5 , J ¼ 7.7, 1.5 Hz), 7.07 (1H, dt,
=
0
H4 , J ¼ 7.4, 1.7 Hz), 6.84 (1H, s, NH). C NMR spectrum, d, ppm: 166.7 (C O),
0
=
150.3 (C-6), 147.9 (C-2), 147.4 (CH N), 137.8 (C-1 ), 133.5 (C-4), 130.2 (C-3),
129.6 (C-30,50), 128.0 (C-40), 122.8 (C-5), 120.7 (C-20,60).
(E)-4-Pyridinecarbaldehyde-N-phenylcarbamoyl oxime 3. IR spectrum,
1
t
max, cmꢁ1: 3210 (N-H), 1710 (C O), 1665 (C N), 980 (N-O). H NMR spectrum,
=
=
=
d, ppm: 8.85 (2H, dd, H2,6, J ¼ 5.2, 0.8 Hz), 8.42 (1H, s, CH N), 7.77 (2H, dd,
0
0
0
0
H
3,5, J ¼ 5.2, 0.8 Hz), 7.53 (2H, dd, H2 ,6 , J ¼ 7.8, 1.5 Hz), 7.34 (2H, dt, H3 ,5 ,
J ¼ 7.8, 7.5 Hz), 7.12 (1H, dt, H4 , J ¼ 7.5, 1.5 Hz), 6.90 (1H, s, NH). 13C NMR spec-
0
0
=
=
trum, d, ppm: 167.4 (C O), 150.2 (C-2,6), 146.9 (CH N), 140.3 (C-4), 138.1 (C-1 ),
128.7 (C-30,50), 124.8 (C-40), 120.3 (C-20,60), 199.5 (C-3,5).
Synthesis of Oxime Carbamates or Thiocarbamates with Alkyl Iso
(or Isothio)cyanates 4–8
Triethylamine (4.1 mL, 0.04 mol) was added to a mixture of ethyl isocyanate or
allyl iso (or isothio)cyanate (0.02 mol) and (E)-2- or 4-pyridinecarbaldehyde oxime
(3.05 g, 0.025 mol) in acetonitrile (40 mL). The mixture was stirred at 45 ꢀC for
7–9 h. The course of the reaction was occasionally monitored by TLC. After com-
pletion of the reaction, the solvent was removed under reduced pressure. Recrystal-
lization of the black residue from a mixture of acetone and CCl4 afforded

1634
A. KOCAK ET AL.
carbamates 4–6. Thiocarbamate derivatives 7 and 8 were obtained oily. Spectral data
of 4–8 are presented.
Selected Data for 4–8
(E)-2-Pyridinecarbaldehyde-N-ethylcarbamoyl oxime 4. IR spectrum,
1
max, cmꢁ1: 3205 (N-H), 1700 (C O), 1660 (C N), 950 (N-O). H NMR spectrum,
=
=
t
=
d, ppm: 8.82 (1H, dd, H6, J ¼ 4.9, 1.8 Hz), 8.51 (1H, s, CH N), 7.88 (1H, dt, H4,
J ¼ 7.8, 1.8 Hz), 7.75 (1H, dd, H3, J ¼ 8.2, 1.4 Hz), 7.36 (1H, dt, H5, J ¼ 7.8,
4.9 Hz), 6.94 (1H, s, NH), 3.21 (2H, q, CH2), 1.17 (3H, t, CH3). 13C NMR spectrum,
=
=
d, ppm: 168.3 (C O), 151.8 (C-2), 149.7 (C-6), 149.0 (CH N), 137.1 (C-4), 124.2
(C-5), 120.1 (C-3), 36.7 (CH2), 16.4 (CH3).
(E)-2-Pyridinecarbaldehyde-N-allylcarbamoyl oxime 5. IR spectrum,
1
t
max, cmꢁ1: 3200 (N-H), 1720 (C O), 1665 (C N), 1610 (C C), 975 (N-O). H
=
=
=
=
NMR spectrum, d, ppm: 8.79 (1H, dd, H6, J ¼ 5.0, 1.7 Hz), 8.54 (1H, s, CH N),
7.90 (1H, dt, H4, J ¼ 7.8, 1.1 Hz), 7.72 (1H, dd, H3, J ¼ 8.2, 1.7 Hz), 7.39 (1H, dt,
H5, J ¼ 7.8, 5.0 Hz), 6.89 (1H, s, NH), 5.96 (1H, m, CH¼CH2), 5.25 (1H, dd,
=
=
CH CH2, J ¼ 16.7, 1.3 Hz), 5.13 (1H, d, CH CH2, J ¼ 9.8), 4.15 (2H, br t, CH2,
13
=
J ¼ 5.6 Hz). C NMR spectrum, d, ppm: 167.9 (C O), 153.0 (C-2), 149.5 (C-6),
=
148.5 (CH N), 137.0 (C-4), 133.8 (CH), 120.2 (C-3), 119.3 (C-5), 116.6 (¼CH2),
42.8 (CH2).
(E)-4-Pyridinecarbaldehyde-N-allylcarbamoyl oxime 6. IR spectrum,
1
max, cmꢁ1: 3210 (N-H), 1705 (C O), 1675 (C N), 1615 (C C), 965 (N-O). H
=
=
=
t
=
NMR spectrum, d, ppm: 8.88 (2H, dd, H2,6, J ¼ 5.3, 0.7 Hz), 8.45 (1H, s, CH N),
7.76 (2H, dd, H3,5, J ¼ 5.3, 0.7 Hz), 6.87 (1H, s, NH), 5.91 (1H, m, CH¼CH2),
13
=
=
5.24 (1H, dd, CH CH2, J ¼ 16.9, 1.4 Hz), 5.14 (1H, d, CH CH2, J ¼ 9.9), 4.10
=
(2H, br t, CH2, J ¼ 5.5 Hz). C NMR spectrum, d, ppm: 167.0 (C O), 151.4
=
(C-2,6), 147.3 (CH N), 141.5 (C-4), 134.2 (CH), 120.2 (C-3,5), 117.8 (¼CH2), 42.6
(CH2).
(E)-2-Pyridinecarbaldehyde-N-allylthiocarbamoyl oxime 7. IR spectrum,
1
max, cmꢁ1: 3215 (N-H), 1680 (C N), 1615 (C C), 1280 (C S), 965 (N-O). H
=
=
=
t
=
NMR spectrum, d, ppm: 8.82 (1H, dd, H6, J ¼ 4.8, 1.8 Hz), 8.50 (1H, s, CH N),
7.92 (1H, dt, H4, J ¼ 7.7, 1.1 Hz), 7.70 (1H, dd, H3, J ¼ 8.1, 1.6 Hz), 7.40 (1H, dt,
H5, J ¼ 7.7, 4.8 Hz), 6.56 (1H, s, NH), 5.76 (1H, m, CH¼CH2), 5.05 (1H, dd,
=
=
CH CH2, J ¼ 16.9, 1.2 Hz), 4.90 (1H, d, CH CH2, J ¼ 9.9), 3.82 (2H, br s, CH2).
13
=
=
C NMR spectrum, d, ppm: 183.2 (C S), 154.4 (C-2), 152.6 (CH N), 150.5
(C-4), 136.5 (C-4) 134.1 (CH), 119.7 (C-3), 188.2 (C-5), 115.3 (¼CH2), 43.2 (CH2).
(E)-4-Pyridinecarbaldehyde-N-allylthiocarbamoyl oxime 8. IR spectrum,
1
max, cmꢁ1: 3210 (N-H), 1675 (C N), 1620 (C C), 1295 (C S), 945 (N-O). H NMR
=
=
=
t
=
spectrum, d, ppm: 8.69 (2H, dd, H2,6, J ¼ 5.2, 0.9 Hz), 8.37 (1H, s, CH N), 7.75 (2H,
dd, H3,5, J ¼ 5.2, 0.9 Hz), 6.61 (1H, s, NH), 5.86 (1H, m, CH¼CH2), 5.25 (1H, dd,
13
=
=
CH CH2, J ¼ 16.5, 1.4 Hz), 5.17 (1H, d, CH CH2, J ¼ 9.4), 4.04 (2H, br s,
=
=
CH2). C NMR spectrum, d, ppm: 184.5 (C S), 152.0 (C-2,6), 146.7 (CH N),
140.8 (C-4), 139.3 (CH), 121.7 (C-3,5), 115.0 (¼CH2), 43.9 (CH2).

OXIME CARBAMATES AND THIOCARBAMATES
1635
Synthesis of Pyridine Carbamates with Phenyl Isocyanate 9 and 10
Triethylamine (10.1 mL, 0.1 mol) was added to a mixture of 2- or 3-hydroxy-
pyridine (9.51 g, 0.1 mol) and phenylisocyanate (11.91 g, 0.1 mol) in a mixture of
DCM and DMSO (1:1, 60 mL). The mixture was stirred at 35 ꢀC for 3–4 h. After
completion of the reaction, the solvents were removed under reduced pressure.
The residue was recrystallized from a mixture of acetonitrile and tetrahydrofurane.
Spectral data of 9 and 10 are presented.
Selected Data for 9 and 10
O-2-Pyridyl-N-phenylcarbamate 9. IR spectrum, tmax, cmꢁ1: 3215 (N-H),
1
=
1715 (C O), 955 (N-O). H NMR spectrum, d, ppm: 8.29 (1H, dd, H6, J ¼ 4.8,
2.1 Hz), 7.57 (1H, dt, H4, J ¼ 8.0, 0.9 Hz), 7.51 (1H, dd, H3, J ¼ 8.0, 1.8 Hz),
0
0
0
0
7.36 (2H, dd, H2 ,6 , J ¼ 7.9, 1.8 Hz), 7.26 (2H, dt, H3 ,5 , J ¼ 7.9, 1.8 Hz), 7.18
13
0
(1H, dt, H5, J ¼ 7.4, 4.8 Hz), 7.01 (1H, dt, H4 , J ¼ 7.4, 1.9 Hz), 6.67 (1H, s,
=
NH). C NMR spectrum, d, ppm: 166.4 (C-2), 165.7 (C O), 141.1 (C-6), 138.2
(C-10), 135.3 (C-4), 128.9 (C-30,50), 128.0 (C-40), 122.4 (C-20,60), 114.7 (C-3), 112.5
(C-5).
O-3-Pyridyl-N-phenylcarbamate 10. IR spectrum, tmax, cmꢁ1: 3210 (N-H),
1
=
1705 (C O), 960 (N-O). H NMR spectrum, d, ppm: 8.47 (1H, t, H2, J ¼ 1.3 Hz), 8.34
0
0
(1H, dd, H6, J ¼ 4.9, 1.6 Hz), 7.77 (1H, td, H4, J ¼ 7.9, 1.6 Hz), 7.27 (2H, dd, H2 ,6 ,
0
0
J ¼ 7.7, 1.5 Hz), 7.17 (1H, dd, H5, J ¼ 7.9, 4.9 Hz), 7.03 (2H, dt, H3 ,5 , J ¼ 7.7,
1.5 Hz), 6.88 (1H, dt, H4 , J ¼ 7.4, 1.6 Hz), 6.64 (1H, s, NH).13C NMR spectrum,
0
0
=
d, ppm: 164.9 (C O), 156.1 (C-3), 140.2 (C-6), 137.8 (C-1 ), 136.2 (C-2), 130.1
(C-30,50), 125.9 (C-40), 125.4 (C-5), 125.0 (C-4), 121.6 (C-20,60).
Synthesis of Pyridine Carbamates or Thiocarbamates with Ally Iso
(or Isothio)cyanate 11–14
A solution of 2- or 4-hydroxypyridine (1.90 g, 0.02 mol) in acetone (20 mL) was
added to a mixture of allyl iso (or isothio)cyanate (0.02 mol) and triethylamine
(2.02 mL, 0.02 mol) in acetone (20 mL). The mixture was stirred at 50 ꢀC for
8–10 h. After completion of the reaction, the products were purified according to
the procedure for 9. Spectral data of 11–14 are presented.
Selected Data for 11–14
O-2-Pyridyl-N-allylcarbamate 11. IR spectrum, tmax, cmꢁ1: 3205 (N-H),
1
=
=
1715 (C O), 1615 (C C), 965 (N-O). H NMR spectrum, d, ppm: 8.31 (1H, dd,
H6, J ¼ 4.6, 2.0 Hz), 7.55 (1H, dt, H4, J ¼ 8.0, 1.0 Hz), 7.43 (1H, dd, H3, J ¼ 8.0,
1.7 Hz), 7.18 (1H, ddt, H5, J ¼ 7.4, 4.6 Hz), 6.58 (1H, s, NH), 5.81 (1H, m,
=
=
CH¼CH2), 5.16 (1H, dd, CH CH2, J ¼ 17.0, 1.5 Hz), 5.01 (1H, d, CH CH2,
J ¼ 10.1), 3.99 (2H, br t, CH2, J ¼ 5.3 Hz).13C NMR spectrum, d, ppm: 166.8
=
(C-2), 165.0 (C O), 140.7 (C-6), 135.3 (C-4), 134.1 (CH), 117.2 (¼CH2), 115.0
(C-3), 113.6 (C-5), 43.9 (CH2).

1636
A. KOCAK ET AL.
O-4-Pyridyl-N-allylcarbamate 12. IR spectrum, tmax, cmꢁ1: 3215 (N-H),
1
=
=
1710 (C O), 1610 (C C), 970 (N-O). H NMR spectrum, d, ppm: 8.41 (2H, dd,
H
2,6, J ¼ 5.5, 0.8 Hz), 7.52 (2H, dd, H3,5, J ¼ 5.5, 0.8 Hz), 6.63 (1H, s, NH), 5.88
13
=
(1H, m, CH¼CH2), 5.31 (1H, dd, CH CH2, J ¼ 17.3, 1.5 Hz), 5.09 (1H, d,
=
CH CH2, J ¼ 9.7), 3.97 (2H, br t, CH2, J ¼ 5.8 Hz). C NMR spectrum, d, ppm:
=
181.4 (C-4), 165.3 (C O), 139.9 (C-2,6), 134.5 (CH), 117.6 (C-3,5), 116.2 (¼CH2),
43.4 (CH2).
O-2-Pyridyl-N-allylthiocarbamate 13. IR spectrum, tmax, cmꢁ1: 3220
(N-H), 1605 (C C), 1275 (C S), 975 (N-O). 1H NMR spectrum, d, ppm: 8.27
(1H, dd, H6, J ¼ 4.7, 2.2 Hz), 7.57 (1H, dt, H4, J ¼ 8.1, 0.9 Hz), 7.41 (1H, dd, H3,
J ¼ 8.1, 1.8 Hz), 7.20 (1H, dt, H5, J ¼ 7.4, 4.7 Hz), 6.48 (1H, s, NH), 5.65 (1H, m,
=
=
=
=
CH¼CH2), 5.03 (1H, dd, CH CH2, J ¼ 16.6, 1.5 Hz), 4. 87 (1H, d, CH CH2,
13
=
J ¼ 9.5), 3.79 (2H, br s, CH2). C NMR spectrum, d, ppm: 184.7 (C S), 165.9
(C-2), 140.9 (C-6), 136.5 (C-4), 135.2 (CH), 115.3 (¼CH2), 114.7 (C-3), 113.0
(C-5), 43.2 (CH2).
O-4-Pyridyl-N-allylthiocarbamate 14. IR spectrum, tmax, cmꢁ1: 3210
(N-H), 1600 (C C), 1280 (C S), 985 (N-O). 1H NMR spectrum, d, ppm: 8.23
(2H, dd, H2,6, J ¼ 5.4, 0.6 Hz), 7.47 (2H, dd, H3,5, J ¼ 5.4, 0.6 Hz), 6.42 (1H, s,
13
=
=
=
NH), 5.57 (1H, m, CH¼CH2), 4.93 (1H, dd, CH CH2, J ¼ 16.6, 1.5 Hz), 4.72
=
(1H, d, CH CH2, J ¼ 9.4), 3.80 (2H, br s, CH2). C NMR spectrum, d, ppm:
=
184.7 (C S), 182.2 (C-4), 140.3 (C-2,6), 133.6 (CH), 116.5 (C-3,5), 115.8 (¼CH2),
44.1 (CH2).
ACKNOWLEDGMENT
We thank the Research Foundation of Selcuk University (SUBAP, Grant No.
07201010) for financial support of this work.
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