Synthesis of 1-Azaazulenes from Cycloheptatrienylmethyl Ketone O-Pentafluorobenzoyloximes by Palladium-Catalyzed Cyclization and Oxidation

Article abstract of DOI:10.1246/bcsj.77.785

Various 1-azaazulenes are synthesized from cycloheptatrienylmethyl ketone O-pentafluorobenzoyloximes by treatment with a catalytic amount of Pd(dba) ₂-t-Bu₃P (dba = dibenzylideneacetone) and triethylamine in the presence of MS 4A via alkylideneaminopalladium(II) intermediates generated by oxidative addition of the oximes to a Pd(0) complex.

Full text of DOI:10.1246/bcsj.77.785

Ó 2004 The Chemical Society of Japan
Bull. Chem. Soc. Jpn., 77, 785–796 (2004)
785
Synthesis of 1-Azaazulenes from Cycloheptatrienylmethyl Ketone
O-Pentafluorobenzoyloximes by Palladium-Catalyzed Cyclization
and Oxidation
ꢀ
Shunsuke Chiba, Mitsuru Kitamura, Osamu Saku, and Koichi Narasaka
Department of Chemistry, Graduate School of Science, The University of Tokyo,
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
Received October 8, 2003; E-mail: narasaka@chem.s.u-tokyo.ac.jp
Various 1-azaazulenes are synthesized from cycloheptatrienylmethyl ketone O-pentafluorobenzoyloximes by treat-
ment with a catalytic amount of Pd(dba)2–t-Bu3P (dba = dibenzylideneacetone) and triethylamine in the presence of MS
4A via alkylideneaminopalladium(II) intermediates generated by oxidative addition of the oximes to a Pd(0) complex.
Azaazulenes are a class of compounds that have been receiv-
ing continual interest from chemists, particularly as regards
their relationship to the chemistry of azulenes as nonbenzenoid
aromatics.1 Among the azaazulene derivatives, 1-azaazulenes
have attracted much attention from the viewpoints of their
physical properties and pharmacological activities. For exam-
ple, it has recently become apparent that 1-azaazulene deriva-
tives exhibit inhibitory activities on histamine release2 and
are useful for treating diseases caused or exacerbated by un-
regulated p38 mitogen-activated protein (MAP) kinase or tu-
mor necrosis factor (TNF)-alpha activity.3 Abe et al. reported
that ethyl 2-dimethylamino-7H-1,7-diazaindeno[1,2-e]azu-
lene-3-carboxylate strongly intercalated to calf-thymus DNA
and 12-mer DNA.4 Furthermore, 1-azaazulenium salts are ap-
plied to organic pigments contained in the optical recording
media such as CD or DVD5 (Fig. 1).
action of N-vinyliminophosphoranes with tropone derivatives
resulted in the formation of 1-azaazulene ring systems.6d Tro-
pone derivatives, however, are very expensive and difficult to
prepare. Accordingly, it is desired to develop new synthetic
routes towards 1-azaazulene derivatives using more easily
available reagents.
We have reported the oxidative addition of oxime deriva-
tives to palladium(0) complexes to generate alkylideneamino-
palladium(II) species.7 This process was applied to the transfor-
mation of olefinic ketone O-pentafluorobenzoyloximes to vari-
ous aza-heterocycles,7a such as pyrrole,7b,c pyridine,7d isoqui-
noline,7d and spiroimine7e,f via the intramolecular Heck-type
reaction (amino-Heck reaction). This amino-Heck reaction is
not affected by the geometry of oximes, probably due to the lin-
ear-like structures of the alkylideneaminometal species.8 Both
E and Z ꢀ,ꢁ-unsaturated ketone oximes cyclize to pyrroles in
good yields (Eq. 1).7b,c
While many groups have researched the synthesis of 1-aza-
azulene derivatives,6 in most cases, tropone derivatives were
used as the starting materials. For example, Nozoe and Seto
et al. developed a synthetic method for 1-azaazulene deriva-
tives using 2-aminotropones.6b,c Nitta et al. reported that the re-
ð1Þ
The amino-Heck reaction was expected to be applicable to
the synthesis of 1-azaazulenes from cycloheptatrienylmethyl
ketone oximes, and we communicated a novel method of 1-
azaazulene synthesis by a palladium(0)-catalyzed cyclization
of cycloheptatrienylmethyl ketone O-pentafluorobenzoylox-
imes via their alkylideneaminopalladium species.9 This article
presents a full account of this catalytic method.
Results and Discussion
Synthetic Plan. The outline of our strategy towards 1-aza-
azulenes based on the amino-Heck reaction is depicted in
Fig. 1. Various 1-azaazulene derivatives.
Published on the web April 2, 2004; DOI 10.1246/bcsj.77.785

786 Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
Synthesis of 1-Azaazulenes
Scheme 3. Synthesis of 1-azaazulene 5a from oxime 1a.
of a Lewis acid (method C).
Reaction of 2-Cycloheptatrienyl-1-phenylethanone O-
Pentafluorobenzoyloxime and Palladium(0) Complex. As
a model compound, 2-cycloheptatrienyl-1-phenylethanone O-
pentafluorobenzoyloxime (1a) was chosen. The amino-Heck
reaction was examined in the presence of palladium(0) caꢁta-
lysts and bases. At first, the reaction was carried out at 80 C
with 0.1 mol. amt. Pd(PPh3)4 and Et3N in DMF, which were
the optimal reaction conditions for the previous pyrrole synthe-
sis.7b,c It took 5 h to consume 1a; after a usual work up,
1H NMR of the crude mixture exhibited the formation of
3,3a-dihydro-2-phenyl-1-azaazulene (4a), a small amount of
the isomers of 4a,12 2-phenyl-1-azaazulene (5a), and ketone
7a. Successive treatment of the crude mixture with MnO2 gave
1-azaazulene 5a and ketone 7a in 25% and 35% yields, respec-
tively13 (Scheme 3).
Scheme 1. Synthesis of 1-azaazulene via the amino-Heck
reaction.
The amino-Heck reaction of 1a was screened under various
reaction conditions concerning additives, palladium catalysts,
ligands, and bases, as shown in Table 1. Addition of MS 4A
was effective to accelerate the reaction and increase the yield
of 1-azaazulene 5a, as was also observed in the previous syn-
thesis of spiroimines (entry 2).7e,f When Pd(dba)2 (dba = diben-
zylideneacetone) and t-Bu3P14,15 were employed as palladium
catalysts, the reaction was finished within 0.5 h. After the oxi-
dation, the yield of 1-azaazulene 5a was improved to 78% and
the formation of ketone 7a was effectively suppressed (entry 5).
Several bases were examined, but no remarkable influence was
observed on the product yields except for DBU (entries 7–10).
Various 1-azaazulenes were prepared by the amino-Heck re-
action with a catalytic amount of Pd(dba)2–t-Bu3P, Et3N, and
MS 4A; the results are summarized in Table 2. In the reaction
of 1b having a bulky tert-butyl group as R1 at 80 ꢁC, it took 4.5
h to consume the starting material 1b; the desired 1-azaazulene
5b was obtained in 64% yield (entry 2). At a higher temperature
(110 ꢁC), the reaction was accelerated and the yield of 5b was
improved to 84% (entry 3). The oximes having secondary alkyl
groups as R1 such as isopropyl 1c and cyclopropyl groups 1d
Scheme 2. Preparation of cycloheptatrienylmethyl ketone oximes.
Scheme 1. The oxidative addition of cyloheptatrienylmethyl
ketone O-pentafluorobenzoyloximes 1 and a Pd(0) complex
would generate alkylideneaminopalladium(II) species 2, which
cyclize to 3,4-dihydro-1-azaazulenes 4 via the formation of ꢂ-
allylpalladium intermediate 3 and the successive hydropalla-
dium(II) elimination. Then, 1-azaazulenes 5 were envisaged
from 3,4-dihydro-1-azaazulenes 4 by oxidation.
Preparation of Cycloheptatrienylmethyl Ketone O-
Pentafluorobenzoyloximes. Cycloheptatrienylmethyl ketone
O-pentafluorobenzoyloximes 1 were prepared from the corre-
sponding cycloheptatrienylmethyl ketones 7 by the oximation
and the O-pentafluorobenzoylation. Ketones 7 were prepared
by the three methods depicted in Scheme 2 from tropylium tet-
rafluoroborate (6) which was commercially available and easily
accessible.10 Reingold et al. reported the acid-catalyzed synthe-
sis of cycloheptatrienylmethyl ketones 7 from tropylium tetra-
fluoroborate (6) and ketones (method A).11 Other preparations
of ketones 7 were achieved by the reaction of 6 with lithium
enolates (method B) or with silyl enol ethers in the presence
ꢁ
cyclized more effectively at 80 C to give the corresponding
1-azaazulenes 5c and d in good yields (entries 4–7). In contrast,
2-methyl-1-azaazulene (5e) was obtained in low yield (entries
8, 9), due to the unstability of 5e under the reaction condi-
tions.16 ꢃ,ꢄ-Unsaturated ketone oxime 1f having a styryl group
was converted to 2-styryl-1-azaazulene (5f) in 68% yield (entry
10), while the oxime 1g of p-methoxystyryl group was convert-
ed to 1-azaazulene 5g in low yield (entry 11). 2,3-Disubstituted
1-azaazulenes 5h–j were prepared in moderate yields at 110 ꢁC
from ꢃ-substituted cycloheptatrienylmethyl ketone O-penta-
fluorobenzoyloximes 1h–j (entries 12–14). In the reaction of
1i, 55% yield of 1-azaazulene 5i was obtained with 3,3a-dihy-

S. Chiba et al.
Table 1. Optimization of Pd-Catalyzed Cyclization of Oxime 1a
Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
787
Pd cat.
base
additive
OCOC6F5
N
N
MnO2
O
+
Ph
DMF
CH2Cl2
Ph
Ph
80 °C
reflux, 2 h
1a
5a
7a
Pd cat.
Base
Yield/%aÞ
Entry
Additive
Time/h
(0.1 mol. amt.)
(3 mol. amt.)
5a
7a
1
2
3
4
5
6
7
8
9
10
Pd(PPh3)4
Pd(PPh3)4
Et3N
Et3N
Et3N
Et3N
Et3N
Et3N
DBU
K2CO3
Cs2CO3
K3PO4
none
5
1.5
2
5.5bÞ
0.5
1
1
0.8
1
25
61
54
19
35
11
34
17
MS 4A
MS 4A
MS 4A
MS 4A
MS 4A
MS 4A
MS 4A
MS 4A
MS 4A
Pd(dba)2 + 2 dppf
PdCl2(dppf) + dppf
Pd(dba)2 + 4 t-Bu3P
Pd(dba)2 + 4 (o-tol)3P
Pd(dba)2 + 4 t-Bu3P
Pd(dba)2 + 4 t-Bu3P
Pd(dba)2 + 4 t-Bu3P
Pd(dba)2 + 4 t-Bu3P
78 (84)cÞ
5 (6)cÞ
(56)cÞ
7
70
54
(14)cÞ
12
9
15
8
1
74
a) Isolated yield. b) 80 ꢁC, 3 h, then 110 ꢁC, 2.5 h. c) 1H NMR yield determined with anthracene as an internal
standard.
Table 2. Synthesis of 1-Azaazulene 5 from Oxime 1 by Amino-Heck Reaction
0.1 mol. amt. Pd(dba)2
0.4 mol. amt. t-Bu3P
C6F5COO
MnO2
Et3N, MS 4A
N
CH2Cl2
reflux, 2 h
R1
DMF
conditions
R2
1
N
O
R1
+
R1
R2
R2
5
7
Oxime
R2
Conditions
Yield/%a)
Entry
R1
1
T/°C
Time/h
5
7
1
2
3
4
5
6
7
8
9
Ph
t-Bu
t-Bu
iso-Pr
iso-Pr
cyclo-Pr
cyclo-Pr
Me
H
H
H
H
H
H
H
H
H
1a
1b
1b
1c
1c
1d
1d
1e
1e
80
80
110
80
110
80
110
80
0.5
4.5
0.5
1
0.3
1.5
0.3
1.5
0.3
5a 78
5b 64
5b 84
5c 62
5c 53
5d 63
5d 51
5e 11
5e 27
7a
7b
7b
7c
5
5
0
4
7c trace
7d
7d
7e
7e
5
3
23
9
Me
110
10
11
H
H
1f
80
1
5f 68
5g 35
7f
2
0
OMe
1g
110
0.3
7g
12
Ph
Ph
Et
Me
Ph
Me
1h
1i
1j
110
110
110
0.5
0.5
0.5
5h 52
5i 55
5j 42
7h
7i
7j
0
4
0
13b)
14
N
a) Isolated yield. b) 4i was obtained in 21% yield.
Ph
Ph
H
H
4i
dro-1-azaazulene 4i in 21% yield; 4i could not be oxidized by
MnO2 (entry 13).17
This method can be applied to the synthesis of polycyclic
azaazulene derivatives. 2-(Cyclohepta-2,4,6-trienyl)-3,4-di-
hydronaphthalen-1(2H)-one (E)-O-pentafluorobenzoyloxime
(1k) cyclized to benzo[g]cyclohepta[b]indole (5k) and 5,6-di-
hydrobenzo[g]cyclohepta[b]indole (5k0) in 50% and 36%
yields respectively (Eq. 2).

788 Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
Synthesis of 1-Azaazulenes
ð2Þ
From the oxime of ꢃ-keto ester 1l, 21% yield of 1-azaazu-
lene 5l was obtained with quinoline 9 and isoquinoline 10 in
18% and 16% yields, respectively (Eq. 3).18
Scheme 5.
ð3Þ
Nitrile Formation. Various 1-azaazulenes were thus pre-
pared from cycloheptatrienylmethyl ketone O-pentafluoroben-
zoyloximes by the palladium-catalyzed amino-Heck reaction
and the successive oxidation, whereas some oximes such as
ꢃ-alkoxy ketoxime and alkynyl ketoxime were transformed
to nitriles under the catalytic conditions. From the ꢃ-methoxy-
methoxy ketone (E)-O-pentafluorobenzoyloxime 1m, nitrile 11
was obtained in 79% yield. Because the nitrile did not form
without the Pd(0) catalyst, the fragmentation maybe proceed
via an alkylideneaminopalladium intermediate (Scheme 4).
A similar fragmentation was observed in the case of ꢃ-
methoxy ketone (Z)-O-pentafluorobenzoyloxime 1n to give
1-methoxy-2-phenylethene in 28% yield, as shown in
Scheme 5. From alkylideneaminopalladium(II) intermediate
2n, the fragmentation reaction occurred to generate oxonium
cation intermediate 12; 1-methoxy-2-phenylethene was then
formed via successive rearrangement.19
Scheme 6.
palladium intermediate and successive decarboxylation21 and
reductive elimination pathways (Scheme 6).
In conclusion, various 1-azaazulenes were synthesized from
cycloheptatrienylmethyl ketone O-pentafluorobenzoyloximes
by the palladium-catalyzed amino-Heck reaction and the suc-
cessive MnO2 oxidation. The reaction proceeds smoothly by
the treatment with a catalytic amount of Pd(dba)2–t-Bu3P,
Et3N, and MS 4A via the formation of alkylideneaminopalla-
dium(II) intermediates. Furthermore, nitriles were formed cat-
alytically from ꢃ-alkoxy ketone oxime and alkynyl ketone ox-
ime derivatives by fragmentation.
Experimental
General. 1H NMR (500 and 270 MHz) spectra were recorded
on Bruker DRX 500, Bruker AVANCE 500, and JEOL AL 270
spectrometers in CDCl3 [using tetramethylsilane (for 1H, ꢁ ¼ 0)
as internal standard], C6D6 [using C6HD5 (for 1H, ꢁ ¼ 7:15) as in-
ternal standard], or DMSO-d6 [using DMSO-d5 (for 1H, ꢁ ¼ 2:49)
as internal standard]. 13C NMR (125 and 67.5 MHz) spectra were
recorded on Bruker DRX 500, Bruker AVANCE 500, and JEOL
AL 270 spectrometers in CDCl3 [using CDCl3 (for 13C,
ꢁ ¼ 77:0) as internal standard], C6D6 [using C6D6 (for 13C,
ꢁ ¼ 128:0) as internal standard], or DMSO-d6 [using DMSO-d6
(for 13C, ꢁ ¼ 39:70) as internal standard]. 19F NMR (470 MHz)
spectra were recorded on Bruker AVANCE 500 spectrometers in
CDCl3 [using C6F6 (for 19F, ꢁ ¼ 0) as internal standard]. IR spec-
tra were recorded on a Horiba FT 300-S by ATR method. High-res-
olution mass spectra were obtained with a JEOL MS-700P mass
spectrometer. The melting points were uncorrected. Elemental
analyses were carried out at The Elemental Analysis Laboratory,
Department of Chemistry, Faculty of Science, The University of
Tokyo. Flash column chromatography was performed on silica
gel [Fuji Silysia Silica gel PSQ-100B and Kanto Chemical Silica
Alkynyl ketone (Z)-O-pentafluorobenzoyloxime 1o also
gave nitrile 11 and 2-pentafluorophenyl-1-phenylacetylene
(13) in 89% and 22% yields, respectively. Formation of penta-
fluorophenylacetylene 13 suggested that nitrile 11 was formed
by the elimination20 of alkynyl group from alkylideneamino-
Scheme 4.

S. Chiba et al.
Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
789
gel 60N (spherical, neutral)] and preparative thin-layer chromatog-
raphy was carried out using Wakogel B-5F. N,N-Dimethylforma-
mide (DMF) was distilled under reduced pressure from P2O5 and
then from CaH2, and stored over molecular sieves 4A under an ar-
gon atmosphere. Dichloromethane was distilled from P2O5 and
then from CaH2, and stored over molecular sieves 4A. Triethyl-
amine was distilled from CaH2 and stored over KOH. Pentafluo-
robenzoyl chloride was purchased from Tokyo Chemical Industry
and was used without purification.
General Procedure for the Synthesis of Cycloheptatrienyl-
methyl Ketones 7. Method A:11 Preparation of 7a is described
below as a typical procedure. A solution of tropylium tetrafluoro-
borate (6) (3.10 g, 17.4 mmol) and acetophenone (1.76 g, 14.6
mmol) in methanol (25 mL) containing 10 drops of acetic acid
was stirred at reflux temperature for 3 h. The reaction was
quenched by water, and organic materials were extracted three
times with ethyl acetate. The combined extracts were washed with
sat. NaHCO3 aq. and brine, and then, dried over anhydrous sodium
sulfate. The solvent was removed in vacuo, and the crude materials
were purified by flash column chromatography (silica gel: hexane/
ethyl acetate = 96/4) to give 2-(cyclohepta-2,4,6-trienyl)-1-phen-
ylethanone (7a) (2.50 g, 68%).
J ¼ 6:2, 9.0 Hz), 6.15–6.19 (2H, m), 6.60–6.65 (2H, m); 13C NMR
(125 MHz, CDCl3) ꢁ 26.3, 34.2, 39.3, 44.1, 125.0, 125.6, 130.8,
214.3; Anal. Found: C, 81.82; H, 9.57%. Calcd for C13H18O: C,
82.06; H, 9.53%.
1-(Cyclohepta-2,4,6-trienyl)-3-methylbutan-2-one (7c): Pre-
pared by method B in 50% yield; Colorless oil; IR (ZnSe) 2969,
1710, 1465, 1363, 1095, 1035, 744, 711 cmꢂ1 1H NMR (500
;
MHz, CDCl3) ꢁ 1.10 (6H, d, J ¼ 7:0 Hz), 2.33 (1H, tt, J ¼ 6:0,
7.0 Hz), 2.60 (1H, septet, J ¼ 7:0 Hz), 2.81 (2H, d, J ¼ 7:0 Hz),
5.17 (2H, dd, J ¼ 6:0, 9.0 Hz), 6.16–6.19 (2H, m), 6.61–6.66
(2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 18.1, 34.3, 40.8, 43.2,
125.1, 125.3, 130.9, 213.3; Anal. Found: C, 81.62; H, 9.12%. Calcd
for C12H16O: C, 81.77; H, 9.15%.
2-(Cyclohepta-2,4,6-trienyl)-1-cyclopropylethanone
(7d):
Prepared by method B in 38% yield; Colorless oil; IR (ZnSe)
3012, 1698, 1390, 1195, 1062, 1022, 900, 744, 703 cmꢂ1; 1H NMR
(500 MHz, CDCl3) ꢁ 0.86 (2H, td, J ¼ 4:0, 6.0 Hz), 1.03 (2H, td,
J ¼ 4:0, 7.5 Hz), 1.93 (1H, tt, J ¼ 5:2, 7.8 Hz), 2.30 (1H, tt,
J ¼ 6:0, 7.5 Hz), 2.92 (2H, d, J ¼ 7:8 Hz), 5.19 (2H, dd,
J ¼ 5:2, 8.8 Hz), 6.16–6.22 (2H, m), 6.62–6.67 (2H, m); 13C NMR
(67.5 MHz, CDCl3) ꢁ 10.7, 20.6, 34.6, 46.5, 125.1, 125.2, 131.0,
209.4; Anal. Found: C, 82.43; H, 8.12%. Calcd for C12H14O: C,
82.72; H, 8.10%.
Method B: Preparation of 7k is described below as a typical
procedure. To an ice cold solution of diisopropylamine (2.6 mL,
19 mmol) in THF (22 mL) was added butyllithium in hexanes
(1.55 M, 9.9 mL, 15 mmol); the mixture was stirred at the same
temperature for 30 min. After cooling to ꢂ78 ꢁC, a solution of
ꢃ-tetralone (2.03 g, 13.9 mmol) in THF (14 mL) was slowly added
to the mixture. After stirring at the same temperature for 50 min,
the THF solution was transferred via cannular to a suspension of
tropylium tetrafluoroborate (6) (3.05 g, 17.1 mmol) in THF (34
mL) at ꢂ78 ꢁC. The reaction mixture was warmed to room temper-
ature over 1.5 h, and then the reaction was quenched with sat.
NH4Cl aq. Organic materials were extracted three times with ethyl
acetate, and the combined extracts were washed with brine. The
ethyl acetate solution was dried over anhydrous sodium sulfate,
and the solvent was removed in vacuo. The crude materials were
purified by flash column chromatography (silica gel: hexane/ethyl
acetate = 95/5) to give 2-(cyclohepta-2,4,6-trienyl)-3,4-dihydro-
naphthalen-1(2H)-one (7k) (2.22 g, 68%).
1-(Cyclohepta-2,4,6-trienyl)-4-phenylbut-3-en-2-one
(7f):
Prepared by method B in 34% yield; Pale yellow oil; IR (ZnSe)
3012, 1687, 1660, 1448, 1365, 1332, 1178, 1062, 975, 744, 688
cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 2.39 (1H, tt, J ¼ 5:9, 7.5
Hz), 3.04 (2H, d, J ¼ 7:5 Hz), 5.25 (2H, dd, J ¼ 5:9, 9.0 Hz),
6.19–6.22 (2H, m), 6.65–6.67 (2H, m), 6.75 (1H, d, J ¼ 16:2
Hz), 7.38–7.41 (3H, m), 7.52–7.55 (2H, m), 7.57 (1H, d, J ¼
16:2 Hz); 13C NMR (125 MHz, C6D6) ꢁ 35.2, 44.1, 125.3, 125.8,
126.5, 128.4, 128.9, 130.2, 131.1, 135.0, 141.9, 197.1;
HRMS(EIþ) Found: m=z 236.1228. Calcd for C17H16O: Mþ,
236.1201.
1-(Cyclohepta-2,4,6-trienyl)-4-(4-methoxyphenyl)but-3-en-
2-one (7g): Prepared by method B in 36% yield; Colorless crys-
tals; mp 98–99 ꢁC; IR (ZnSe) 3004, 2931, 1652, 1598, 1509, 1421,
1249, 1174, 1024, 968, 842, 696 cmꢂ1 1H NMR (270 MHz,
;
CDCl3) ꢁ 2.38 (1H, tt, J ¼ 5:6, 7.2 Hz), 3.01 (2H, d, J ¼ 7:2
Hz), 3.84 (3H, s), 5.25 (2H, dd, J ¼ 5:6 8.9 Hz), 6.17–6.23 (2H,
m), 6.64 (1H, d, J ¼ 15:9 Hz), 6.66–6.70 (2H, m), 6.91 (2H, d, J ¼
8:6 Hz), 7.50 (2H, d, J ¼ 8:6 Hz), 7.53 (1H, d, J ¼ 15:9 Hz);
13C NMR (67.5 MHz, CDCl3) ꢁ 35.0, 43.7, 55.4, 114.4, 124.0,
125.1, 125.3, 127.1, 130.0, 131.0, 142.6, 161.6, 198.7; Anal.
Found: C, 80.97; H, 6.94%. Calcd for C18H18O2: C, 81.17; H,
6.81%.
Method C: Preparation of 7l is described below as a typical
procedure. To an ice cold solution of tropylium tetrafluoroborate
(6) (1.95 g, 10.9 mmol) and ethyl 2-trimethylsiloxyacrylate22
(2.25 g, 12.1 mmol) in dichloromethane (25 mL) was added a solu-
tion of BF3 Et2O (1.87 g, 13.1 mmol) in dichloromethane (5 mL).
ꢃ
After stirring at room temperature for 2 h, the reaction was
quenched with water, and organic materials were extracted three
times with ethyl acetate. The combined extracts were washed with
brine and dried over anhydrous sodium sulfate. The solvent was re-
moved in vacuo, and the crude materials were purified by flash col-
umn chromatography (silica gel: hexane/ethyl acetate = 90/10) to
give ethyl 3-(cyclohepta-2,4,6-trienyl)propionate (7l) (911 mg,
40%).
2-(Cyclohepta-2,4,6-trienyl)-1-phenylpropan-1-one
Prepared by method B in 50% yield; Colorless oil; IR (ZnSe)
3014, 1677, 1446, 1222, 1180, 968, 686 cmꢂ1 1H NMR (500
(7h):
;
MHz, CDCl3) ꢁ 1.29 (3H, d, J ¼ 7:0 Hz), 2.35 (1H, ddd,
J ¼ 6:2, 6.3, 9.2 Hz), 3.83 (1H, qd, J ¼ 7:0, 9.2 Hz), 5.24 (1H,
dd, J ¼ 6:2, 9.5 Hz), 5.38 (1H, dd, J ¼ 6:3, 9.5 Hz), 6.14 (1H,
dd, J ¼ 5:0, 9.5 Hz), 6.27 (1H, dd, J ¼ 4:9, 9.5 Hz), 6.62–6.68
(2H, m), 7.47 (2H, dd, J ¼ 7:4, 7.9 Hz), 7.57 (1H, tt, J ¼ 1:3,
7.4 Hz), 7.95 (2H, dd, J ¼ 1:3, 7.9 Hz); 13C NMR (125 MHz,
CDCl3) ꢁ 15.8, 41.6, 41.7, 123.1, 125.0, 125.2, 125.6, 128.3,
128.7, 130.8, 130.9, 133.0, 136.8, 203.5; Anal. Found: C, 85.90;
H, 7.43%. Calcd for C16H16O: C, 85.68; H, 7.19%.
2-(Cyclohepta-2,4,6-trienyl)-1,2-diphenylethanone (7i): Pre-
pared by method A in 59% yield; Colorless needles; mp 116–118
ꢁC; IR (ZnSe) 3018, 1677, 1569, 1579, 1492, 1446, 1274, 1218,
1176, 983, 754, 692, 653 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ
;
Spectral Data. 2-(Cyclohepta-2,4,6-trienyl)-1-phenylethanone
(7a) and 1-(cyclohepta-2,4,6-trienyl)propan-2-one (7e) are known
compounds, and their spectral data are in good agreement with
those of authentic samples.11
1-(Cyclohepta-2,4,6-trienyl)-3,3-dimethylbutan-2-one (7b):
Prepared by method B in 30% yield; Colorless oil; IR (ZnSe)
2954, 2879, 1700, 1465, 1403, 1365, 1207, 1120, 989, 752, 690
1
cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 1.18 (9H, s), 2.38 (1H, tt,
J ¼ 6:2, 7.1 Hz), 2.84 (2H, d, J ¼ 7:1 Hz), 5.18 (2H, dd,

790 Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
Synthesis of 1-Azaazulenes
3.08 (1H, ddd, J ¼ 6:4, 6.7, 11.1 Hz), 4.84 (1H, d, J ¼ 11:1 Hz),
5.16 (1H, dd, J ¼ 6:7, 9.6 Hz), 5.36 (1H, dd, J ¼ 6:4, 9.5 Hz),
6.13–6.20 (2H, m), 6.67–6.69 (2H, m), 7.19–7.23 (1H, m), 7.26–
7.31 (4H, m), 7.39 (2H, dd, J ¼ 7:5, 7.9 Hz), 7.49 (1H, tt,
J ¼ 1:2, 7.4 Hz), 7.95 (2H, d, J ¼ 8:4 Hz); 13C NMR (125 MHz,
CDCl3) ꢁ 42.2, 53.7, 123.6, 125.3, 125.8 (overlapped), 127.3,
128.5, 128.6, 128.8, 128.9, 130.7, 130.9, 133.0, 137.0, 137.3,
199.1; Anal. Found: C, 87.84; H, 6.54%. Calcd for C21H18O: C,
88.08; H, 6.34%.
4-(Cyclohepta-2,4,6-trienylmethyl)-1-phenylbut-1-yn-3-one
(7o): Prepared by method B in 40% yield; Pale yellow oil; IR
(ZnSe) 3014, 2198, 1664, 1488, 1398, 1116, 1066, 757, 688
1
cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 2.45 (1H, td, J ¼ 5:8, 7.5
Hz), 3.02 (2H, d, J ¼ 7:5 Hz), 5.25 (2H, dd, J ¼ 5:8, 9.1 Hz),
6.21–6.25 (2H, m), 6.68–6.69 (2H, m), 7.38 (2H, dd, J ¼ 7:3,
7.6 Hz), 7.45 (1H, t, J ¼ 7:6 Hz), 7.55 (2H, dd, J ¼ 7:3 Hz);
13C NMR (125 MHz, CDCl3) ꢁ 34.8, 48.2, 87.9, 91.2, 119.8,
124.5, 125.4, 128.6, 130.8, 131.1, 133.1, 186.5; HRMS(EIþ)
Found: m=z 234.1017. Calcd for C17H14O: Mþ, 234.1045.
2-(Cyclohepta-2,4,6-trienyl)pentan-3-one (7j): Prepared by
method A in 58% yield; Colorless oil; IR (ZnSe) 3016, 2973,
;
1712, 1600, 1457, 1376, 1106, 971, 744, 707 cmꢂ1 1H NMR
General Procedure for the Preparation of Cycloheptatri-
enylmethyl Ketone Oximes 8. To a solution of 2-(cyclohepta-
2,4,6-trienyl)-1-phenylethanone (7a) (1.86 g, 8.82 mmol) and pyr-
idine (1.1 mL, 14 mmol) in ethanol (15 mL) was added hydroxyl-
amine hydrochloride (0.92 g, 13 mmol); the mixture was stirred at
(500 MHz, CDCl3) ꢁ 1.04 (3H, dd, J ¼ 7:3, 7.3 Hz), 1.08 (3H,
d, J ¼ 7:0 Hz), 2.04 (1H, ddd, J ¼ 6:1, 6.2, 9.4 Hz), 2.40 (1H,
qd, J ¼ 7:3, 17.8 Hz), 2.46 (1H, qd, J ¼ 7:3, 17.8 Hz), 2.87 (1H,
qd, J ¼ 7:0, 9.4 Hz), 5.17 (1H, dd, J ¼ 6:1, 9.4 Hz), 5.23 (1H,
dd, J ¼ 6:2, 9.4 Hz), 6.18 (1H, ddd, J ¼ 2:5, 3.2, 9.4 Hz), 6.24
(1H, ddd, J ¼ 2:4, 3.2, 9.4 Hz), 6.63–6.68 (2H, m); 13C NMR
(125 MHz, CDCl3) ꢁ 7.6, 14.7, 34.4, 41.2, 47.6, 122.9, 124.2,
125.2, 125.5, 130.85, 130.87, 214.4; Anal. Found: C, 81.60; H,
9.29%. Calcd for C12H16O: C, 81.77; H, 9.15%.
2-(Cyclohepta-2,4,6-trienyl)-3,4-dihydronaphthalen-1(2H)-
one (7k): Colorless oil; IR (ZnSe) 3019, 2933, 2836, 1675, 1598,
1455, 1361, 1224, 1029, 900, 792, 700 cmꢂ1; 1H NMR (500 MHz,
CDCl3) ꢁ 2.14–2.21 (2H, m), 2.32–2.38 (1H, m), 2.89–2.93 (1H,
m), 2.99–3.02 (2H, m), 5.31 (1H, dd, J ¼ 6:0, 9.4 Hz), 5.45 (1H,
dd, J ¼ 5:9, 9.4 Hz), 6.20–6.26 (2H, m), 6.63–6.68 (2H, m),
7.22 (1H, d, J ¼ 7:6 Hz), 7.29 (1H, dd, J ¼ 7:4, 7.6 Hz), 7.45
(1H, dd, J ¼ 7:4, 7.8 Hz), 8.02 (1H, d, J ¼ 7:8 Hz); 13C NMR
(125 MHz, CDCl3) ꢁ 26.2, 28.1, 38.7, 49.1, 122.8, 124.5 (overlap-
ped), 125.2, 126.6, 127.4, 128.6, 130.6, 131.1, 132.7, 133.2, 143.6,
199.3; Anal. Found: C, 86.10; H, 6.95%. Calcd for C17H16O: C,
86.40; H, 6.82%.
ꢁ
60 C for 12 h. After the reaction was quenched with water, the
mixture was extracted three times with ethyl acetate, and the com-
bined extracts were washed with brine. The solution was dried over
anhydrous sodium sulfate, and ethyl acetate was removed in vacuo.
The crude materials were purified by flash column chromatography
(silica gel: hexane/ethyl acetate = 75/25) to give 2-(cyclohepta-
2,4,6-trienyl)-1-phenylethanone (E)-oxime (8a) (1.88 g, 95%).
Spectral Data. 2-(Cyclohepta-2,4,6-trienyl)-1-phenyletha-
none (E)-Oxime (8a):
(KBr) 3199, 3018, 1496, 1444, 1398, 1321, 1085, 998, 931, 767,
White powder; mp 134–135 ꢁC; IR
1
698 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 1.97 (1H, tt, J ¼ 5:5,
8.1 Hz), 3.28 (2H, d, J ¼ 8:1 Hz), 5.26 (2H, dd, J ¼ 5:5, 9.1
Hz), 6.11–6.13 (2H, m), 6.54–6.59 (2H, m), 7.34–7.36 (3H, m),
7.55–7.58 (2H, m), 8.88 (1H, brs); 13C NMR (125 MHz, CDCl3)
ꢁ 28.9, 36.9, 125.1, 125.3, 126.4, 128.6, 129.2, 131.0, 135.6,
158.4; Anal. Found: C, 80.02; H, 6.81; N, 6.18%. Calcd for
C15H15NO: C, 79.97; H, 6.71; N, 6.22%.
1-(Cyclohepta-2,4,6-trienyl)-3,3-dimethylbutan-2-one (E)-
Oxime (8b): Prepared as above in 89% yield; White powder;
mp 90–92 ꢁC; IR (ZnSe) 3226, 2965, 1467, 1392, 1207, 1126,
;
1031, 929, 773, 690 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 1.13
(9H, s), 1.99 (1H, tt, J ¼ 5:7, 7.6 Hz), 2.85 (2H, d, J ¼ 7:6 Hz),
5.35 (2H, dd, J ¼ 5:7, 9.0 Hz), 6.14–6.18 (2H, m), 6.62–6.67
(2H, m), 9.34 (1H, br); 13C NMR (125 MHz, CDCl3) ꢁ 28.4,
28.7, 37.5, 37.6, 124.4, 126.3, 130.9, 165.6; Anal. Found: C,
75.85; H, 9.49; N, 6.73%. Calcd for C13H19NO: C, 76.06; H,
9.33; N, 6.82%.
Ethyl 3-(Cyclohepta-2,4,6-trienyl)propionate (7l): Colorless
oil; IR (ZnSe) 3014, 1747, 1731, 1446, 1398, 1276, 1052, 852, 707
cmꢂ1; 1H NMR (500 MHz, CDCl3) ꢁ 1.37 (3H, t, J ¼ 7:3 Hz), 2.39
(1H, tt, J ¼ 6:0, 7.3 Hz), 3.19 (2H, d, J ¼ 7:3 Hz), 4.32 (2H, q, J ¼
7:3 Hz), 5.20 (2H, dd, J ¼ 6:0, 9.3 Hz), 6.19–6.24 (2H, m), 6.64–
6.68 (2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 13.9, 33.7, 42.1,
62.5, 124.3, 125.5, 131.0, 160.9, 193.2; Anal. Found: C, 69.74;
H, 6.99%. Calcd for C12H14O3: C, 69.88; H, 6.84%.
1-(Cyclohepta-2,4,6-trienyl)-3-methoxymethoxy-3-methyl-
butan-2-one (7m): Prepared by method B in 34% yield; Colorless
oil; IR (ZnSe) 2987, 2935, 1716, 1463, 1400, 1361, 1143, 1025,
1-(Cyclohepta-2,4,6-trienyl)-3-methylbutan-2-one
(8c): Prepared as above in 94% yield; E:Z = 3:1 mixture; Color-
Oxime
1
919, 707 cmꢂ1; H NMR (270 MHz, CDCl3) ꢁ 1.36 (6H, s), 2.32
less oil; IR (ZnSe) 3270, 2964, 1756, 1700, 1652, 1457, 1365,
1240, 944, 746, 703 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 1.07
;
(1H, tt, J ¼ 5:9, 7.3 Hz), 3.01 (2H, d, J ¼ 7:3 Hz), 3.38 (3H, s),
4.72 (2H, s), 5.19 (2H, dd, J ¼ 5:9, 9.2 Hz), 6.16–6.20 (2H, m),
6.62–6.65 (2H, m); 13C NMR (67.5 MHz, CDCl3) ꢁ 23.6, 34.1,
39.4, 55.5, 82.1, 92.1, 125.0, 125.5, 130.9, 212.0; Anal. Found:
C, 71.05; H, 8.68%. Calcd for C14H20O3: C, 71.16; H, 8.53%.
2-(Cyclohepta-2,4,6-trienyl)-2-methoxy-1-phenylethanone
(7n): Prepared by method B in 58% yield; Pale yellow oil; IR
(ZnSe) 3021, 2362, 1689, 1596, 1448, 1199, 1133, 744, 703
(1.5H, d, J ¼ 7:1 Hz), 1.09 (4.5H, d, J ¼ 6:9 Hz), 1.96 (0.75H,
tt, J ¼ 5:6, 8.2 Hz), 2.03 (0.25H, tt, J ¼ 5:5, 7.8 Hz), 2.43
(0.75H, septet, J ¼ 6:9 Hz), 2.58 (0.5H, d, J ¼ 7:8 Hz), 2.84
(1.5H, d, J ¼ 8:2 Hz), 3.41 (0.25H, septet, J ¼ 7:1 Hz), 5.19
(0.5H, dd, J ¼ 5:5, 9.1 Hz), 5.25 (1.5H, dd, J ¼ 5:6, 9.1 Hz),
6.16–6.19 (2H, m), 6.62–6.68 (2H, m); 13C NMR (125 MHz,
CDCl3) ꢁ 18.8, 20.3, 26.4, 29.4, 32.8, 33.8, 35.6, 36.5, 124.6,
124.9, 125.7, 126.0, 130.9, 131.0, 163.3, 164.0; Anal. Found: C,
75.20; H, 8.93; N, 7.24%. Calcd for C12H17NO: C, 75.35; H,
8.96; N, 7.32%.
2-(Cyclohepta-2,4,6-trienyl)-1-cyclopropylethanone Oxime
(8d): Prepared as above in 96% yield; E:Z = 4:1 mixture; Color-
less oil; IR (ZnSe) 3259, 3010, 1643, 1438, 1398, 1240, 1024, 943,
696 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 0.65–0.73 (3.6H, m),
;
cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 2.24 (1H, ddd, J ¼ 5:6,
5.7, 6.8 Hz), 3.46 (3H, s), 4.78 (1H, d, J ¼ 6:8 Hz), 5.28 (1H,
dd, J ¼ 5:7, 9.4 Hz), 5.47 (1H, dd, J ¼ 5:6, 9.5 Hz), 6.19 (1H,
J ¼ 4:9, 9.4 Hz), 6.22 (1H, dd, J ¼ 4:9, 9.5 Hz), 6.57–6.63 (2H,
m), 7.44 (2H, dd, J ¼ 7:4, 7.8 Hz), 7.56 (1H, t, J ¼ 7:4 Hz),
8.02 (2H, d, J ¼ 7:8 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 41.9,
58.2, 84.9, 121.1, 121.5, 122.5, 125.6, 128.60, 128.66, 130.7,
131.2, 133.5, 135.3, 199.3; Anal. Found: C, 79.82; H, 6.83%. Calcd
for C16H16O2: C, 79.97; H, 6.71%.
0.84–0.86 (0.4H, m), 1.38 (0.8H, tt, J ¼ 5:3, 7.9 Hz), 1.98
(0.2H, tt, J ¼ 5:6, 7.6 Hz), 2.05 (0.8H, tt, J ¼ 5:5, 8.1 Hz), 2.23

S. Chiba et al.
Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
791
(0.4H, d, J ¼ 7:6 Hz), 2.31 (0.2H, tt, J ¼ 5:5, 8.5 Hz), 2.86 (1.6H,
d, J ¼ 8:1 Hz), 5.18 (0.4H, dd, J ¼ 5:6, 9.0 Hz), 5.27 (1.6H, dd,
J ¼ 5:5, 9.0 Hz), 6.15–6.20 (2H, m), 6.63–6.65 (0.4H, m), 6.66–
6.70 (1.6H, m), 8.12 (0.8H, br), 8.39 (0.2H, br); 13C NMR (125
MHz, CDCl3) ꢁ 4.8 (overlapped), 5.8 (overlapped), 8.6, 13.9,
31.4, 32.5, 35.8, 36.5, 124.7, 124.8, 125.7 (overlapped), 130.9,
131.0, 159.2, 160.8; Anal. Found: C, 76.03; H, 8.03; N, 7.36%.
Calcd for C12H15NO: C, 76.16; H, 7.99; N, 7.40%.
1-(Cyclohepta-2,4,6-trienyl)propan-2-one Oxime (8e): Pre-
pared as above in 99% yield; Colorless oil; IR (ZnSe) 3226, 2910,
1668, 1430, 1367, 1162, 1041, 952, 707, 686 cmꢂ1; (E)-isomer
1H NMR (500 MHz, CDCl3) ꢁ 1.85 (3H, s), 1.92 (1H, tt,
J ¼ 5:5, 7.9 Hz), 2.61 (2H, d, J ¼ 7:9 Hz), 5.18 (2H, dd,
J ¼ 5:5, 9.0 Hz), 6.17–6.19 (2H, m), 6.65–6.67 (2H, m), 9.31
(1H, br); 13C NMR (125 MHz, CDCl3) ꢁ 13.4, 35.8, 39.1, 125.0,
125.1, 130.9, 157.0; (Z)-isomer 1H NMR (500 MHz, CDCl3) ꢁ
1.85 (3H, s), 1.91 (1H, tt, J ¼ 5:5, 8.2 Hz), 2.86 (2H, d, J ¼ 8:2
Hz), 5.22 (2H, dd, J ¼ 5:5, 9.0 Hz), 6.17–6.21 (2H, m), 6.66–
6.68 (2H, m), 9.44 (1H, br); 13C NMR (125 MHz, CDCl3) ꢁ
19.7, 31.5, 36.0, 125.0, 125.3, 131.0, 157.2; Anal. Found: C,
73.44; H, 8.07; N, 8.41%. Calcd for C10H13NO: C, 73.59; H,
8.03; N, 8.58%.
J ¼ 5:0, 9.3 Hz), 6.62–6.67 (2H, m), 6.80 (0.75H, d, J ¼ 16:5
Hz), 6.87 (0.75H, d, J ¼ 16:5 Hz), 6.20–6.25 (1.5H, m), 6.61–
6.68 (2H, m), 7.19 (1H, d, J ¼ 8:2 Hz), 7.25–7.39 (4H, m), 8.25
(0.5H, br), 8.81 (0.5H, br); 13C NMR (125 MHz, CDCl3) ꢁ 15.5,
16.2, 35.4, 41.80, 41.83, 42.4, 123.4 (overlapped), 124.5, 124.6,
124.7, 124.8 (overlapped), 125.0, 127.4, 127.8, 128.1, 128.2,
128.5, 128.6, 130.7, 130.85, 130.98, 130.9, 133.0, 135.7, 162.1,
163.2; Anal. Found: C, 80.13; H, 7.01; N, 5.65%. Calcd for
C16H17NO: C, 80.30; H, 7.16; N, 5.85%.
2-(Cyclohepta-2,4,6-trienyl)-1,2-diphenylethanone Oxime
(8i): Prepared as aꢁbove in 96% yield; E:Z = 1:1 mixture; White
solid; mp 136–138 C; IR (ZnSe) 3261, 3059, 3022, 2871, 1601,
1495, 1452, 1442, 1301, 1070, 947, 746, 696 cmꢂ1 1H NMR
;
(500 MHz, DMSO-d6, 50 ꢁC) ꢁ 2.29 (0.5H, ddd, J ¼ 5:6, 6.0,
12.3 Hz), 2.33 (0.5H, ddd, J ¼ 5:6, 5.7, 11.7 Hz), 4.14 (0.5H, d,
J ¼ 11:7 Hz), 5.01 (0.5H, dd, J ¼ 6:0, 9.4 Hz), 5.12 (0.5H, dd,
J ¼ 5:6, 9.2 Hz), 5.24 (0.5H, dd, J ¼ 5:7, 9.3 Hz), 5.35 (0.5H, d,
J ¼ 12:3 Hz), 5.48 (0.5H, dd, J ¼ 5:6, 9.2 Hz), 6.02 (0.5H, dd,
J ¼ 5:4, 9.4 Hz), 6.16 (0.5H, dd, J ¼ 5:4, 9.3 Hz), 6.19 (0.5H,
dd, J ¼ 5:2, 9.2 Hz), 6.25 (0.5H, dd, J ¼ 5:6, 9.2 Hz), 6.59–6.71
(2H, m), 6.99–7.00 (1H, m), 7.07 (1H, d, J ¼ 7:1 Hz), 7.13 (1H,
d, J ¼ 7:1 Hz), 7.17–7.30 (7H, m), 10.73 (0.5H, brs), 11.39
ꢁ
1-(Cycloheptatrienyl)-4-phenylbut-3-en-2-one Oxime (8f):
Prepared as above in 87% yield; E:Z = 3:1 mixture; Colorless nee-
(0.5H, brs); 13C NMR (125 MHz, DMSO-d6, 50 C) ꢁ 39.1, 41.3,
44.0, 52.1, 116.8, 117.4, 117.62, 117.65, 117.7, 118.1, 118.2,
119.2, 119.7, 120.66 (overlapped), 120.71, 120.8, 120.9, 121.2.
121.3, 121.4, 121.6, 121.7, 123.3, 123.47, 123.52, 123.7, 127.3,
128.4, 131.3, 132.0, 147.2, 148.6; Anal. Found: C, 80.13; H,
7.01; N, 5.65%. Calcd for C21H19NO: C, 83.69; H, 6.35; N, 4.65%.
2-(Cyclohepta-2,4,6-trienyl)pentan-3-one Oxime (8j): Pre-
pared as above in 96% yield; E:Z = 4:1 mixture; Colorless oil;
IR (ZnSe) 3239, 2969, 1648, 1457, 1376, 1087, 950, 929, 707
ꢁ
dles; mp 114–115 C; IR (ZnSe) 3172, 3016, 2861, 1621, 1446,
1
1259, 1207, 750, 696 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 2.09
(0.25H, tt, J ¼ 5:5, 7.8 Hz), 2.15 (0.75H, tt, J ¼ 5:6, 8.2 Hz),
2.92 (0.5H, d, J ¼ 7:8 Hz), 3.12 (1.5H, d, J ¼ 8:2 Hz), 5.29
(0.5H, dd, J ¼ 5:5, 9.2 Hz), 5.36 (1.5H, dd, J ¼ 5:6, 9.2 Hz),
6.17–6.19 (2H, m, overlapped), 6.62–6.67 (2H, m), 6.80 (0.75H,
d, J ¼ 16:5 Hz), 6.87 (0.75H, d, J ¼ 16:5 Hz), 6.93 (0.25H, d, J ¼
16:8 Hz), 7.25–7.36 (3H, m), 7.44 (1.5H, d, J ¼ 7:7 Hz), 7.51
(0.5H, d, J ¼ 7:4 Hz), 7.53 (0.25H, d, J ¼ 16:8 Hz), 9.40 (1H,
br); 13C NMR (125 MHz, DMSO-d6) ꢁ 26.8, 33.9, 36.7, 37.1,
116.6, 124.6, 124.9, 125.7, 126.2, 126.4, 126.9, 127.3, 128.3,
128.9, 129.02, 129.05, 131.0, 131.1, 131.6, 134.1, 136.4, 136.5,
152.5, 156.7; Anal. Found: C, 81.36; H, 7.00; N, 5.51%. Calcd
for C17H17NO: C, 81.24; H, 6.82; N, 5.57%.
cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 1.086 (0.6H, dd, J ¼ 7:3,
7.3 Hz), 1.093 (2.4H, dd, J ¼ 7:6, 7.6 Hz), 1.18 (0.6H, d, J ¼
7:0 Hz), 1.23 (2.4H, d, J ¼ 6:9 Hz), 1.48 (0.2H, ddd, J ¼ 5:7,
5.7, 11.6 Hz), 1.66 (0.8H, ddd, J ¼ 5:8, 5.8, 10.3 Hz), 2.06–2.14
(0.4H, m), 2.17 (0.8H, qd, J ¼ 7:6, 12.9 Hz), 2.32 (0.8H, qd,
J ¼ 7:6, 12.9 Hz), 2.75 (0.8H, qd, J ¼ 6:9, 10.3 Hz), 3.81 (0.2H,
qd, J ¼ 7:0, 11.6 Hz), 5.14 (0.2H, dd, J ¼ 5:7, 9.3 Hz), 5.22–
5.25 (1.8H, m), 6.15–6.18 (1H, m), 6.22–6.26 (1H, m), 6.65–
6.72 (2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 10.2, 10.4, 15.3,
16.1, 19.5, 22.8, 33.9, 41.3, 41.9, 42.2, 123.6, 124.1, 124.4,
124.5, 124.7, 124.8, 125.0, 125.1, 130.7 (overlapped), 130.9,
131.0, 164.0, 164.9; Anal. Found: C, 75.17; H, 8.96; N, 7.29%.
Calcd for C12H17NO: C, 75.35; H, 8.96; N, 7.32%.
1-(Cyclohepta-2,4,6-trienyl)-4-(4-methoxyphenyl)but-3-en-
2-one Oxime (8g): Prepared as above in 93% yield; E:Z = 3:1
ꢁ
mixture; White powder; mp 126–127 C; IR (ZnSe) 3170, 3012,
1602, 1509, 1245, 1174, 1031, 964, 696 cmꢂ1 1H NMR (500
;
MHz, CDCl3) ꢁ 2.05–2.15 (1H, m), 2.90 (0.5H, d, J ¼ 7:8 Hz),
3.09 (1.5H, d, J ¼ 8:1 Hz), 3.81 (2.25H, s), 3.82 (0.75H, s), 5.28
(0.5H, dd, J ¼ 5:4, 9.1 Hz), 5.35 (1.5H, dd, J ¼ 5:5, 9.1 Hz),
6.17–6.19 (2H, m), 6.63–6.65 (2H, m), 6.67 (0.75H, d, J ¼ 16:6
Hz), 6.81 (0.75H, d, J ¼ 16:6 Hz), 6.85–6.89 (2.25H, m), 7.36–
7.40 (1.75H, m), 7.46 (0.5H, d, J ¼ 8:7 Hz), 9.25 (0.25H, br),
9.40 (0.75H, br); 13C NMR (125 MHz, CDCl3) ꢁ 27.1, 34.2,
36.7, 37.2, 55.3 (overlapped), 113.9, 114.1, 122.9 (overlapped),
124.8, 125.1, 125.4, 125.6, 128.2, 128.9, 129.0, 131.0, 131.1,
132.9 (overlapped), 135.4, 154.7, 158.6, 159.9, 160.4; Anal.
Found: C, 76.67; H, 6.91; N, 4.86%. Calcd for C18H19NO2: C,
76.84; H, 6.81; N, 4.98%.
2-(Cyclohepta-2,4,6-trienyl)-1-phenylpropan-1-one Oxime
(8h): Prepared as above in 98% yield; E:Z = 1:1 mixture; Color-
less oil; IR (ZnSe) 3249, 3016, 1635, 1496, 1442, 1376, 1307, 948,
916, 769 cmꢂ1; 1H NMR (500 MHz, CDCl3) ꢁ 1.24 (1.5H, d, J ¼
6:9 Hz), 1.29 (1.5H, d, J ¼ 7:0 Hz), 1.65 (0.5H, ddd, J ¼ 5:8, 5.8,
9.8 Hz), 1.90 (0.5H, ddd, J ¼ 5:8, 5.8, 11.5 Hz), 3.04 (0.5H, qd,
J ¼ 6:9, 9.8 Hz), 3.89 (0.5H, qd, J ¼ 7:0, 11.5 Hz), 5.23–5.29
(1.5H, m), 5.41 (0.5H, dd, J ¼ 5:8, 9.3 Hz), 6.14 (0.5H, dd,
2-(Cyclohepta-2,4,6-trienyl)-3,4-dihydronaphthalen-1(2H)-
one (E)-Oxime (8k): Prepared as above in 95% yield; Colorless
needles; mp 164–165 ꢁC; IR (ZnSe) 3226, 3014, 2931, 2362, 1625,
1596, 1486, 1454, 1396, 1317, 1078, 954, 742, 696 cmꢂ1; 1H NMR
(500 MHz, CDCl3) ꢁ 1.63 (1H, ddd, J ¼ 5:4, 5.6, 11.5 Hz), 2.03
(1H, dddd, J ¼ 3:6, 6.2, 11.7, 13.8 Hz), 2.33 (1H, dddd, J ¼ 2:6,
3.4, 5.5, 13.8 Hz), 2.67–2.79 (2H, m), 4.13 (1H, ddd, J ¼ 3:4,
3.6, 11.5 Hz), 5.30 (1H, dd, J ¼ 5:6, 9.3 Hz), 5.53 (1H, dd,
J ¼ 5:4, 9.3 Hz), 6.13 (1H, dd, J ¼ 5:3, 9.3 Hz), 6.24 (1H, dd,
J ¼ 5:3, 9.3 Hz), 6.58 (1H, dd, J ¼ 5:3, 10.8 Hz), 6.62 (1H, dd,
J ¼ 5:3, 10.8 Hz), 7.07 (1H, d, J ¼ 7:7 Hz), 7.16 (1H, dd,
J ¼ 7:5, 7.7 Hz), 7.23 (1H, dd, J ¼ 7:5, 7.9 Hz), 7.84 (1H, d, J ¼
7:9 Hz), 8.19 (1H, br); 13C NMR (125 MHz, CDCl3) ꢁ 24.1, 24.2,
33.2, 38.7, 122.9, 124.7, 124.9, 125.17, 125.21, 126.3, 128.9,
129.3, 129.9, 130.5, 131.3, 138.1, 158.0; Anal. Found: C, 81.30;
H, 6.93; N, 5.47%. Calcd for C17H17NO: C, 81.24; H, 6.82; N,
5.57%.
Ethyl 3-(Cyclohepta-2,4,6-trienyl)-2-hydroxyiminopropio-

792 Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
Synthesis of 1-Azaazulenes
nate (8l): Prepared as above in 95% yield; Colorless oil; IR
(ZnSe) 3226, 3014, 1716, 1432, 1307, 1288, 1180, 1128, 1014,
705 cmꢂ1; (E)-isomer 1H NMR (500 MHz, CDCl3) ꢁ 1.33 (3H, t,
J ¼ 7:2 Hz), 2.06 (1H, tt, J ¼ 5:5, 8.0 Hz), 3.07 (2H, d, J ¼ 8:0
Hz), 4.29 (2H, q, J ¼ 7:2 Hz), 5.25 (2H, dd, J ¼ 5:5, 9.1 Hz),
6.15–6.17 (2H, m), 6.62–6.67 (2H, m), 10.0 (1H, br); 13C NMR
(125 MHz, CDCl3) ꢁ 14.0, 27.8, 36.7, 61.9, 124.9, 125.1, 131.0,
151.2, 163.5; (Z)-isomer 1H NMR (500 MHz, CDCl3) ꢁ 1.32
(3H, t, J ¼ 6:8 Hz), 2.02 (1H, tt, J ¼ 5:6, 7.8 Hz), 2.84 (2H, d, J ¼
7:8 Hz), 4.31 (2H, q, J ¼ 6:8 Hz), 5.22 (2H, dd, J ¼ 5:6, 9.3 Hz),
6.16–6.22 (2H, m), 6.63–6.68 (2H, m), 11.3 (1H, brs); 13C NMR
(125 MHz, CDCl3) ꢁ 13.9, 34.3, 36.1, 62.0, 124.7, 125.1, 131.0,
147.5, 163.4; Anal. Found: C, 64.92; H, 6.79; N, 6.23%. Calcd
for C12H15NO3: C, 65.15; H, 6.83; N, 6.33%.
min. After the reaction was quenched with water, the mixture was
extracted three times with ethyl acetate, and the combined extracts
were washed with sat. NaHCO3 aq. and brine. The solution was
dried over anhydrous sodium sulfate, and ethyl acetate was re-
moved in vacuo. The crude materials were purified by flash column
chromatography (silica gel: hexane/ethyl acetate = 95/5) to give
2-(cyclohepta-2,4,6-trienyl)-1-phenylethanone (E)-O-pentafluoro-
benzoyloxime (1a) (1.43 g, 95%).
Spectral Data. 2-(Cyclohepta-2,4,6-trienyl)-1-phenyletha-
none (E)-O-Pentafluorobenzoyloxime (1a): Prepared as above
in 95% yield; White powder; mp 88–89 ꢁC; IR (KBr) 3021,
1766, 1650, 1527, 1494, 1332, 1199, 1002, 887, 788, 701, 615
cmꢂ1
;
1H NMR (270 MHz, CDCl3) ꢁ 1.99 (1H, tt, J ¼ 5:6, 8.1
Hz), 3.29 (2H, d, J ¼ 8:1 Hz), 5.15 (2H, dd, J ¼ 5:6, 9.2 Hz),
6.10–6.14 (2H, m), 6.50–6.55 (2H, m), 7.35–7.46 (3H, m), 7.65–
7.68 (2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 31.2, 36.8, 106.9–
107.2 (m), 123.8, 125.6, 127.5, 128.7, 130.9, 131.0, 133.0, 137.8
(m, d, J ¼ 254 Hz), 143.5 (m, d, J ¼ 254 Hz), 145.4 (m, d, J ¼
253 Hz), 156.4, 167.5; Anal. Found: C, 63.19; H, 3.50; N,
3.36%. Calcd for C22H14F5NO2: C, 63.01; H, 3.37; N, 3.34%.
1-(Cyclohepta-2,4,6-trienyl)-3,3-dimethylbutan-2-one (E)-
O-Pentafluorobenzoyloxime (1b): Prepared as above in 99%
yield; White powder; mp 73–74 ꢁC; IR (ZnSe) 2971, 2362,
1-(Cyclohepta-2,4,6-trienyl)-3-methoxymethoxy-3-methyl-
butan-2-one (E)-Oxime (8m): Prepared as above in 93% yield;
Colorless oil; IR (ZnSe) 3351, 2985, 2937, 1436, 1380, 1143, 1083,
1
1029, 944, 700 cmꢂ1; H NMR (500 MHz, C6D6) ꢁ 1.38 (6H, s),
2.27 (1H, tt, J ¼ 5:5, 7.9 Hz), 2.98 (2H, d, J ¼ 7:9 Hz), 3.10
(3H, s), 4.49 (2H, s), 5.41 (2H, dd, J ¼ 5:5, 9.0 Hz), 6.07–6.10
(2H, m), 6.51–6.53 (2H, m), 9.45 (1H, brs); 13C NMR (125
MHz, CDCl3) ꢁ 26.1, 28.7, 38.0, 55.1, 78.6, 91.9, 124.7, 126.5,
131.2, 162.4; Anal. Found: C, 66.75; H, 8.33; N, 5.32%. Calcd
for C14H21NO3: C, 66.91; H, 8.42; N, 5.57%.
1762, 1652, 1496, 1322, 1187, 993, 856, 700 cmꢂ1 1H NMR
;
2-(Cyclohepta-2,4,6-trienyl)-2-methoxy-1-phenylethanone
Oxime (8n): ꢁ Prepared as above in 86% yield; Colorless crystals;
mp 165–166 C; IR (ZnSe) 3272, 2929, 1490, 1440, 1336, 1124,
(500 MHz, CDCl3) ꢁ 1.23 (9H, s), 1.96 (1H, tt, J ¼ 6:0, 7.6 Hz),
2.88 (2H, d, J ¼ 7:6 Hz), 5.19 (2H, dd, J ¼ 6:0, 9.1 Hz), 6.12–
6.15 (2H, m), 6.63–6.64 (2H, m); 13C NMR (125 MHz, CDCl3)
ꢁ 28.1, 31.1, 37.4, 38.8, 107.4–107.7 (m), 124.7, 124.9, 131.0,
137.6 (m, d, J ¼ 254 Hz), 143.2 (m, d, J ¼ 258 Hz), 145.1 (m,
d, J ¼ 256 Hz), 156.7, 175.6; Anal. Found: C, 60.03; H, 4.58; N,
3.50%. Calcd for C20H18F5NO2: C, 60.15; H, 4.54; N, 3.51%.
1-(Cyclohepta-2,4,6-trienyl)-3-methylbutan-2-one O-Penta-
fluorobenzoyloxime (1c): Prepared as above in 98% yield; E:Z
= 2:1 mixture; Colorless oil; IR (ZnSe) 2973, 1760, 1652, 1502,
1
1106, 1068, 941, 927, 763, 694, 582 cmꢂ1; (E)-isomer H NMR
(500 MHz, CDCl3) ꢁ 1.81 (1H, ddd, J ¼ 5:5, 5.8, 10.1 Hz), 3.55
(3H, s), 4.19 (1H, d, J ¼ 10:1 Hz), 5.15 (1H, dd, J ¼ 5:8, 9.4
Hz), 5.39 (1H, dd, J ¼ 5:5, 9.4 Hz), 6.16–6.21 (2H, m), 6.53
(1H, dd, J ¼ 5:2, 10.9 Hz), 6.57 (1H, dd, J ¼ 5:4, 10.9 Hz),
7.32–7.36 (5H, m), 8.71 (1H, brs); 13C NMR (125 MHz, CDCl3)
ꢁ 41.7, 57.3, 84.4, 120.7, 123.4, 125.2, 125.7, 128.02, 128.04,
129.0, 130.4, 130.6, 131.2, 156.8; (Z)-isomer 1H NMR (500
MHz, CDCl3) ꢁ 2.05 (1H, ddd, J ¼ 5:5, 5.8, 10.7 Hz), 3.50 (3H,
s), 5.11 (1H, dd, J ¼ 5:8, 9.5 Hz), 5.47 (1H, d, J ¼ 10:7 Hz),
5.48 (1H, dd, J ¼ 5:5, 9.4 Hz), 6.12 (1H, dd, J ¼ 5:5, 9.5 Hz),
6.25 (1H, dd, J ¼ 5:5, 9.4 Hz), 6.53 (1H, dd, J ¼ 5:5, 11.0 Hz),
6.61 (1H, dd, J ¼ 5:5, 11.0 Hz), 7.29–7.36 (3H, m), 7.64–7.67
(2H, m), 9.30 (1H, brs); 13C NMR (125 MHz, CDCl3) ꢁ 42.3,
57.8, 75.3, 120.0, 124.0, 125.3, 126.0, 127.8, 128.3, 129.2,
130.8, 131.1, 133.4, 158.1; Anal. Found: C, 75.03; H, 6.74; N,
5.61%. Calcd for C16H17NO2: C, 75.27; H, 6.71; N, 5.49%.
4-(Cyclohepta-2,4,6-trienyl)-1-phenylbut-1-yn-3-one Oxime
(8o): E:Z = 2:3 mixture; Pale yellow oil; IR (ZnSe) 3247,
3172, 3014, 2856, 2217, 1608, 1490, 1442, 1313, 1149, 1020,
1326, 1195, 1091, 997, 896, 700 cmꢂ1 1H NMR (500 MHz,
;
CDCl3) ꢁ 1.10 (2H, d, J ¼ 7:1 Hz), 1.20 (4H, d, J ¼ 6:9 Hz),
2.03 (0.67H, tt, J ¼ 5:8, 8.1 Hz), 2.09 (0.33H, tt, J ¼ 5:7, 7.8
Hz), 2.64 (0.67H, septet, J ¼ 6:9 Hz), 2.74 (0.66H, d, J ¼ 7:8
Hz), 2.86 (1.34H, d, J ¼ 8:1 Hz), 3.32 (0.33H, septet, J ¼ 7:1
Hz), 5.17 (1.34H, dd, J ¼ 5:8, 9.1 Hz), 5.22 (0.66H, dd, J ¼ 5:7,
9.1 Hz), 6.16–6.21 (2H, m), 6.64–6.67 (2H, m); 13C NMR (125
MHz, CDCl3) ꢁ 18.9, 20.0, 29.2, 31.4, 33.7, 33.9, 35.4, 36.4,
107.2–107.7 (m, overlapped), 124.2, 124.9, 125.0, 125.5, 130.9,
131.1, 136.6–136.8 and 138.6–138.8 (m, d, overlapped), 142.2–
142.4, 143.9–144.4, and 146.0–146.3 (m, overlapped), 156.7,
157.4, 173.5, 174.1; Anal. Found: C, 59.35; H, 4.33; N, 3.63%.
Calcd for C19H16F5NO2: C, 59.22; H, 4.19; N, 3.64%.
987, 755, 707 cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 2.18–2.22
2-(Cyclohepta-2,4,6-trienyl)-1-cyclopropylethanone O-Pen-
tafluorobenzoyloxime (1d): Prepared as above in 98% yield;
E:Z = 5:3 mixture; Colorless oil; IR (ZnSe) 3016, 1758, 1506,
(1H, m), 2.83 (1.2H, d, J ¼ 7:8 Hz), 2.99 (0.8H, d, J ¼ 8:0 Hz),
5.27–5.32 (2H, m), 6.21–6.23 (2H, m), 6.66–6.70 (2H, m), 7.25–
7.38 (3H, m), 7.44 (0.8H, d, J ¼ 7:0 Hz), 7.50 (1.2H, d, J ¼ 7:0
Hz), 9.14 (0.6 H, brs), 9.32 (0.4H, brs); 13C NMR (125 MHz,
CDCl3) ꢁ 31.9, 36.4, 36.6, 37.3, 79.6, 84.2, 92.0, 101.0, 121.4,
121.8, 124.9, 125.1, 125.2, 125.3, 128.3, 128.4, 129.1, 129.5,
131.0 (overlapped), 131.9, 132.1, 141.9, 146.3.
General Procedure for the Preparation of Cycloheptatri-
enylmethyl Ketone O-Pentafluorobenzoyloximes 1. To 2-(cy-
clohepta-2,4,6-trienyl)-1-phenylethanone (E)-oxime (8a) (819
mg, 3.64 mmol) and triethylamine (1.00 mL, 7.17 mmol) in di-
chloromethane (20 mL), a solution of pentafluorobenzoyl chloride
(1.07 g, 4.64 mmol) in dichloromethane (5 mL) was slowly added
at 0 ꢁC, and this mixture was stirred at the same temperature for 15
1421, 1326, 1201, 1095, 1002, 869, 700 cmꢂ1 1H NMR (500
;
MHz, CDCl3) ꢁ 0.81–0.85 (0.74H, m), 0.85–0.89 (1.26H, m),
0.96–1.00 (0.74H, m), 1.01–1.04 (1.26H, m), 1.54 (0.63H, tt,
J ¼ 5:0, 8.2 Hz), 2.04 (0.37H, tt, J ¼ 5:7, 7.7 Hz), 2.14 (0.63H,
tt, J ¼ 5:9, 8.1 Hz), 2.26 (0.37H, tt, J ¼ 5:2, 8.5 Hz), 2.37
(0.74H, d, J ¼ 7:7 Hz), 2.90 (1.26H, d, J ¼ 8:1 Hz), 5.20
(1.26H, dd, J ¼ 5:9, 9.3 Hz), 5.23 (0.74H, dd, J ¼ 5:7, 9.3 Hz),
6.16–6.22 (2H, m), 6.63–6.65 (0.74H, m), 6.66–6.69 (1.26H, m);
13C NMR (125 MHz, CDCl3) ꢁ 6.3 (overlapped), 7.7 (overlapped),
10.4, 14.1, 32.0, 33.5, 35.8, 36.3, 107.0–107.2 (m), 107.3–107.6
(m), 124.2, 124.8, 125.0, 125.4, 130.9, 131.1, 136.5–136.8 and
138.5–138.8 (m, d, overlapped), 142.1–142.3, 144.0–144.4, and

S. Chiba et al.
Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
793
146.2–146.4 (m, overlapped), 156.4, 157.2, 169.9, 171.6; Anal.
Found: C, 59.31; H, 3.78; N, 3.61%. Calcd for C19H14F5NO2: C,
59.53; H, 3.68; N, 3.65%.
128.0, 128.1, 128.3, 128.4, 128.8, 129.2, 130.0, 130.3, 130.85,
130.89, 130.94, 130.99, 131.6, 133.0, 136.5–136.9 and 138.5–
138.9 (m, d, overlapped), 142.2–142.4, 144.2–144.5, and 146.2–
146.4 (m, overlapped), 156.5, 156.9, 172.6, 172.7; Anal. Found:
C, 63.56; H, 3.73; N, 3.21%. Calcd for C23H16F5NO2: C, 63.74;
H, 3.72; N, 3.23%.
1-(Cyclohepta-2,4,6-trienyl)propan-2-one (E)-O-Pentafluo-
robenzoyloxime (1e): Prepared as above in 92% yield; Colorless
oil; IR (ZnSe) 3018, 1760, 1652, 1523, 1506, 1421, 1326, 1197,
1
1093, 1002, 873, 713 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 1.96
2-(Cyclohepta-2,4,6-trienyl)-1,2-diphenylethanone O-Penta-
fluorobenzoyloxime (1i): Prepared as above in 99% yield; E:Z
= 1:1 mixture; White amorphous material; IR (ZnSe) 3021,
(1H, tt, J ¼ 5:5, 8.0 Hz), 2.01 (3H, s), 2.80 (2H, d, J ¼ 8:0 Hz),
5.22 (2H, dd, J ¼ 5:5, 9.1 Hz), 6.19–6.26 (2H, m), 6.66–6.71
(2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 15.7, 35.7, 38.6, 107.0–
107.3 (m), 124.0, 125.4, 131.1, 137.7 (m, d, J ¼ 254 Hz), 143.3
(m, d, J ¼ 259 Hz), 145.4 (m, d, J ¼ 252 Hz), 156.7, 167.6; Anal.
Found: C, 57.33; H, 3.53; N, 3.92%. Calcd for C17H12F5NO2: C,
57.15; H, 3.39; N, 3.92%.
1762, 1652, 1496, 1324, 1189, 1002, 873, 698 cmꢂ1 1H NMR
;
(500 MHz, CDCl3) ꢁ 2.19 (0.5H, ddd, J ¼ 5:7, 5.9, 12.3 Hz),
2.45 (0.5H, ddd, J ¼ 6:0, 6.1, 12.3 Hz), 4.39 (0.5H, d, J ¼ 12:3
Hz), 5.05 (0.5H, dd, J ¼ 6:1, 9.4 Hz), 5.12 (0.5H, dd, J ¼ 5:7,
9.3 Hz), 5.33 (0.5H, dd, J ¼ 5:9, 9.3 Hz), 5.35 (0.5H, d, J ¼
12:3 Hz), 5.68 (0.5H, dd, J ¼ 6:0, 9.4 Hz), 6.14 (0.5H, dd,
J ¼ 5:6, 9.4 Hz), 6.18 (0.5H, dd, J ¼ 4:8, 9.3 Hz), 6.32 (0.5H,
dd, J ¼ 4:8, 9.3 Hz), 6.39 (0.5H, dd, J ¼ 5:6, 9.4 Hz), 6.65–6.75
(3H, m), 6.97–6.98 (1H, m), 7.12–7.15 (2H, m), 7.18–7.21 (2H,
m), 7.27–7.33 (4H, m); 13C NMR (125 MHz, CDCl3) ꢁ 41.9,
42.6, 50.2, 55.1, 104.5–104.7 (m, overlapped), 118.6, 119.80,
119.83, 120.5, 121.3, 121.4, 121.5, 122.2, 122.7, 123.76, 123.79
(overlapped), 123.9, 124.5, 124.7, 124.8, 124.99, 125.1, 125.3,
125.7, 126.56, 126.58, 126.8, 127.0, 127.3, 127.6, 131.1, 131.5,
132.8 (m, d, J ¼ 234 Hz), 133.1 (m, d, J ¼ 234 Hz), 138.1 (m,
d, J ¼ 238 Hz), 138.4 (m, d, J ¼ 238 Hz), 139.8 (m, d, J ¼ 237
Hz), 140.1 (m, d, J ¼ 237 Hz), 150.3, 150.7, 163.0, 163.2; Anal.
Found: C, 67.80; H, 3.79; N, 2.89%. Calcd for C28H18F5NO2: C,
67.88; H, 3.66; N, 2.83%.
1-(Cyclohepta-2,4,6-trienyl)-4-phenylbut-3-en-2-one O-Pen-
tafluorobenzoyloxime (1f): Prepared as above in 95% yield;
E:Z = 4:1 mixture; White powder; mp 156–157 ꢁC, dec.; IR
(ZnSe) 3018, 1754, 1650, 1625, 1492, 1322, 1186, 1000, 869,
690 cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 2.08 (0.2H, tt,
J ¼ 5:6, 7.9 Hz), 2.22 (0.8H, tt, J ¼ 5:9, 8.1 Hz), 3.10 (0.4H, d,
J ¼ 7:9 Hz), 3.13 (1.6H, d, J ¼ 8:1 Hz), 5.27 (1.6H, dd,
J ¼ 5:9, 9.1 Hz), 5.32 (0.4H, dd, J ¼ 5:6, 9.2 Hz), 6.19–6.22
(2H, m, overlapped), 6.63–6.65 (2H, m, overlapped), 6.96 (0.8H,
d, J ¼ 16:5 Hz), 7.08 (0.2H, d, J ¼ 16:6 Hz), 7.13 (0.8H, d, J ¼
16:5 Hz), 7.31–7.40 (3.2H, m, overlapped), 7.48–7.51 (2H, m,
overlapped); 13C NMR (125 MHz, CDCl3) ꢁ 29.1, 33.8, 37.0,
37.2, 106.6–106.9 (m, overlapped), 115.5, 122.4, 124.0, 124.6,
125.1, 125.7, 127.4, 127.9, 128.9, 129.0, 129.7, 130.3, 131.1,
131.2, 134.9, 135.2, 136.6–136.9 and 138.7–138.9 (m, d, overlap-
ped), 139.0, 140.7, 142.5–142.7, 144.5–144.7, and 146.5–146.7
(m, overlapped), 156.4, 156.8, 163.0, 166.3; Anal. Found: C,
64.81; H, 3.77; N, 3.06%. Calcd for C24H16F5NO2: C, 64.72; H,
3.62; N, 3.14%.
2-(Cyclohepta-2,4,6-trienyl)pentan-3-one
benzoyloxime (1j): Prepared as above in 94% yield; E:Z = 4:1
O-Pentafluoro-
mixture; Colorless oil; IR (ZnSe) 2977, 1756, 1652, 1496, 1322,
1
1182, 1089, 995, 856, 700 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ
1.11 (2.4H, dd, J ¼ 7:6, 7.6 Hz), 1.20 (0.6H, dd, J ¼ 7:3, 7.3
Hz), 1.23 (0.6H, d, J ¼ 7:0 Hz), 1.32 (2.4H, d, J ¼ 6:9 Hz), 1.59
(0.2H, ddd, J ¼ 5:9, 5.9, 11.6 Hz), 1.68 (0.8H, ddd, J ¼ 5:9, 6.0,
10.7 Hz), 2.17–2.39 (2H, m), 3.03 (0.8H, qd, J ¼ 6:9, 10.7 Hz),
3.62 (0.2H, qd, J ¼ 7:0, 11.6 Hz), 5.04 (0.2H, dd, J ¼ 5:9, 9.2
Hz), 5.20 (0.2H, dd, J ¼ 5:6, 9.3 Hz), 5.24 (0.8H, dd, J ¼ 5:9,
8.9 Hz), 5.26 (0.8H, dd, J ¼ 6:0, 8.8 Hz), 6.18–6.22 (1H, m),
6.25–6.29 (1H, m), 6.65–6.72 (2H, m); 13C NMR (125 MHz,
CDCl3) ꢁ 10.3, 10.9, 15.6, 16.0, 21.0, 13.8, 36.9, 41.4, 41.7,
41.8, 107.2–107.3 (m, overlapped), 122.6, 122.8, 122.9, 123.7,
124.8 (overlapped), 125.4, 125.5, 130.90 (overlapped), 130.94,
130.99, 136.6–136.7 and 138.6–138.8 (m, d, overlapped), 142.2–
142.3, 144.2–144.3, and 146.2–146.3 (m, overlapped), 156.9
(overlapped), 174.7, 175.2; Anal. Found: C, 59.34; H, 4.35; N,
3.59%. Calcd for C19H16F5NO2: C, 59.22; H, 4.19; N, 3.64%.
2-(Cyclohepta-2,4,6-trienyl)-3,4-dihydronaphthalen-1(2H)-
one (E)-O-Pentafluorobenzoyloxime (1k): Prepared as above in
95% yield; White powder; mp 137–138 ꢁC; IR (ZnSe) 2937, 1758,
1650, 1590, 1494, 1326, 1191, 1000, 919, 862, 700 cmꢂ1; 1H NMR
(500 MHz, CDCl3) ꢁ 1.76 (1H, td, J ¼ 5:9, 11.6 Hz), 2.05–2.13
(1H, m), 2.34–2.40 (1H, m), 2.73–2.84 (2H, m), 3.97 (1H, ddd,
J ¼ 3:4, 3.4, 11.6 Hz), 5.28 (2H, dd, J ¼ 5:9, 9.2 Hz), 6.14 (1H,
dd, J ¼ 5:7, 9.2 Hz), 6.27 (1H, dd, J ¼ 5:6, 9.2 Hz), 6.52 (1H,
dd, J ¼ 5:7, 11.0 Hz), 6.62 (1H, dd, J ¼ 5:6, 11.0 Hz), 7.11 (1H,
d, J ¼ 7:7 Hz), 7.21 (1H, dd, J ¼ 7:5, 7.7 Hz), 7.34 (1H, dd,
J ¼ 7:5, 7.8 Hz), 8.05 (1H, d, J ¼ 7:8 Hz); 13C NMR (125 MHz,
CDCl3) ꢁ 23.7, 24.0, 35.7, 38.0, 106.9–107.2 (m), 121.9, 122.7,
125.7, 125.9, 126.6, 126.7, 127.5, 129.0, 130.7, 131.2, 131.3,
137.8 (m, d, J ¼ 254 Hz), 139.4, 143.4 (m, d, J ¼ 254 Hz),
145.4 (m, d, J ¼ 252 Hz), 156.6, 166.6; Anal. Found: C, 64.65;
1-(Cyclohepta-2,4,6-trienyl)-4-(4-methoxyphenyl)but-3-en-
2-one (E)-O-Pentafuluorobenzoyloxime (1g):
above in 95% yield; White powder; IR (ZnSe) 3023, 1754, 1648,
1602, 1488, 1243, 1184, 1002, 910, 829, 698 cmꢂ1 1H NMR
Prepared as
;
(500 MHz, CDCl3) ꢁ 2.21 (1H, tt, J ¼ 5:8, 8.1 Hz), 3.10 (2H, d,
J ¼ 8:1 Hz), 3.83 (3H, s), 5.26 (2H, dd, J ¼ 5:8, 9.1 Hz), 6.18–
6.22 (2H, m), 6.61–6.65 (2H, m), 6.82 (1H, d, J ¼ 16:4 Hz),
6.90 (2H, d, J ¼ 8:8 Hz), 7.08 (1H, d, J ¼ 16:4 Hz), 7.43 (2H,
d, J ¼ 8:8 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 29.1, 37.3, 55.4,
106.8–107.0 (m), 114.1, 120.1, 124.2, 125.7, 128.1, 128.8, 131.1,
137.8 (m, d, J ¼ 254 Hz), 138.6, 143.5 (m, d, J ¼ 253 Hz),
145.5 (m, d, J ¼ 258 Hz), 156.4, 160.9, 166.6; Anal. Found: C,
62.93; H, 3.92; N, 2.84%. Calcd for C25H18F5NO3: C, 63.16; H,
3.82; N, 2.95%.
2-(Cyclohepta-2,4,6-trienyl)-1-phenylpropan-1-one O-Pen-
tafluorobenzoyloxime (1h): Prepared as above in 89% yield;
E:Z = 1:1 mixture; Colorless oil; IR (ZnSe) 3018, 2362, 1762,
1652, 1498, 1324, 1191, 993, 862, 700 cmꢂ1 1H NMR (500
;
MHz, CDCl3) ꢁ 1.31 (1.5H, d, J ¼ 6:9 Hz), 1.34 (1.5H, d, J ¼
7:0 Hz), 1.67 (0.5H, ddd, J ¼ 5:9, 6.0, 10.6 Hz), 1.87 (0.5H,
ddd, J ¼ 5:8, 6.0, 11.5 Hz), 3.30 (0.5H, qd, J ¼ 6:9, 10.6 Hz),
3.81 (0.5H, qd, J ¼ 7:0, 11.5 Hz), 5.17 (0.5H, dd, J ¼ 6:0, 9.3
Hz), 5.24 (0.5H, dd, J ¼ 6:0, 9.4 Hz), 5.27 (0.5H, dd, J ¼ 5:8,
9.4 Hz), 5.48 (0.5H, dd, J ¼ 5:9, 9.3 Hz), 6.17 (0.5H, dd,
J ¼ 5:5, 9.3 Hz), 6.25 (1H, dd, J ¼ 5:4, 9.4 Hz), 6.29 (0.5H, dd,
J ¼ 5:2, 9.3 Hz), 6.57–6.70 (2H, m), 7.08–7.11 (1H, m), 7.32–
7.45 (4H, m); 13C NMR (125 MHz, CDCl3) ꢁ 15.8, 15.9, 38.0,
41.5, 42.0, 42.1, 106.9–107.2 (m, overlapped), 122.5, 123.2,
123.4, 123.9, 124.7, 125.0, 125.4, 125.5, 125.6, 126.5, 126.8,

794 Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
Synthesis of 1-Azaazulenes
H, 3.81; N, 3.05%. Calcd for C24H16F5NO2: C, 64.72; H, 3.62; N,
3.14%.
three times with ether, and the combined extracts were washed suc-
cessively with water three times and with brine. The ether solution
was dried over anhydrous magnesium sulfate; then the ether was
removed in vacuo. The crude products were dissolved in dichloro-
methane (5.0 mL), and MnO2 (932 mg, 10.7 mmol) was added to
the solution. The mixture was stirred at the reflux temperature for 2
h and then filtered through a celite pad. The dichloromethane was
removed in vacuo, and the crude materials were purified by flash
column chromatography (silica gel: benzene/acetone/triethyl-
amine = 95:5:1) to give 2-(cyclohepta-2,4,6-trienyl)-1-phenyl-
ethanone (7a) (3.8 mg, 5%) and the mixture of 2-phenyl-1-azaazu-
lene (5a) and t-butylphosphine oxide. Finally, the mixture was pu-
rified by column chromatography on SephadexTM LH-20 to give 2-
phenyl-1-azaazulene (5a) (57.2 mg, 78%).
Ethyl 3-(Cyclohepta-2,4,6-trienyl)-2-[(E)-pentafluoroben-
zoyloxyimino]propionate (1l): Prepared as above in 91% yield;
Colorless oil; IR (ZnSe) 3018, 1772, 1727, 1650, 1496, 1322, 1176,
1
1000, 867, 703 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 1.38 (3H, t,
J ¼ 7:1 Hz), 2.17 (1H, tt, J ¼ 5:5, 8.1 Hz), 3.11 (2H, d, J ¼ 8:1
Hz), 4.38 (2H, q, J ¼ 7:1 Hz), 5.22 (2H, dd, J ¼ 5:5, 9.3 Hz),
6.17–6.21 (2H, m), 6.61–6.66 (2H, m); 13C NMR (125 MHz,
CDCl3) ꢁ 28.5, 42.5, 48.0, 71.1, 108.25–108.5 (m), 123.6, 125.6,
130.2, 136.1 (m, d, J ¼ 224 Hz), 141.3 (m, d, J ¼ 226 Hz),
142.9 (m, d, J ¼ 224 Hz), 151.4, 155.9, 157.3; Anal. Found: C,
54.78; H, 3.60; N, 3.41%. Calcd for C19H14F5NO4: C, 54.95; H,
3.40; N, 3.37%.
1-(Cyclohepta-2,4,6-trienyl)-3-methoxymethoxy-3-methyl-
butan-2-one (E)-O-Pentafluorobenzoyloxime (1m): Prepared as
above in 89% yield; Colorless oil; IR (ZnSe) 3019, 1741, 1652,
Spectral Data. 2-Phenyl-1-azaazulene (5a): Red powder;
ꢁ
mp 158–159 C; IR (ZnSe) 3388, 3019, 1573, 1508, 1436, 1214,
1025, 769, 752 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 7.45 (1H,
;
1525, 1496, 1328, 1205, 1002, 921, 688 cmꢂ1
;
1H NMR (500
tt, J ¼ 1:5, 7.3 Hz), 7.52 (2H, dd, J ¼ 7:3, 7.7 Hz), 7.59 (1H,
dd, J ¼ 9:9, 10.1 Hz), 7.73 (1H, dd, J ¼ 9:0, 9.5 Hz), 7.76 (1H,
s), 7.78 (1H, dd, J ¼ 9:0, 10.1 Hz), 8.32 (2H, dd, J ¼ 1:5, 7.7
Hz), 8.50 (1H, d, J ¼ 9:8 Hz), 8.66 (1H, d, J ¼ 9:5 Hz); 13C NMR
(125 MHz, CDCl3) ꢁ 110.7, 128.1, 128.8, 128.9, 129.6, 129.9,
134.6, 135.2, 135.3, 136.6, 148.0, 158.7, 167.2; Anal. Found: C,
87.78; H, 5.51; N, 6.70%. Calcd for C15H11N: C, 87.77; H, 5.40;
N, 6.82%.
MHz, C6D6) ꢁ 1.41 (6H, s), 2.23 (1H, td, J ¼ 5:6, 7.8 Hz), 2.96
(2H, d, J ¼ 7:8 Hz), 3.06 (3H, s), 4.43 (2H, s), 5.24 (2H, dd,
J ¼ 5:6, 9.1 Hz), 6.04–6.08 (2H, m), 6.48–6.50 (2H, m); 13C NMR
(125 MHz, C6D6) ꢁ 25.9, 30.9, 37.7, 55.3, 78.9, 91.7, 107.3–107.5
(m), 125.0, 125.2, 131.3, 137.6 (m, d, J ¼ 252 Hz), 143.5 (m, d,
J ¼ 253 Hz), 145.4 (m, d, J ¼ 255 Hz), 155.9, 173.1.
2-(Cyclohepta-2,4,6-trienyl)-2-methoxy-1-phenylethanone
(Z)-O-Pentafluorobenzoyloxime (1n): Prepared as above in 99%
yield; Colorless oil; IR (ZnSe) 3021, 2830, 1762, 1652, 1496,
2-Phenyl-3,3a-dihydrocyclohepta[b]pyrrole (4a):
1
Yellow
oil; H NMR (500 MHz, CDCl3) ꢁ 3.09–3.14 (2H, m), 3.72 (1H,
dd, J ¼ 11:6, 19.6 Hz), 5.30 (1H, dd, J ¼ 3:3, 9.6 Hz), 6.12 (1H,
ddd, J ¼ 2:0, 6.0, 9.6 Hz), 6.36 (1H, dd, J ¼ 6:0, 10.8 Hz),
6.52–6.59 (2H, m), 7.42–7.50 (3H, m), 7.95 (2H, d, J ¼ 6:9 Hz);
13C NMR (125 MHz, CDCl3) ꢁ 38.9, 43.3, 115.6, 124.2, 126.8,
128.1, 128.8, 130.0, 131.7, 134.2, 155.3, 157.5, 178.6.
1
1324, 1184, 1081, 993, 933, 871, 696 cmꢂ1; H NMR (500 MHz,
CDCl3) ꢁ 1.80 (1H, ddd, J ¼ 5:5, 5.9, 10.3 Hz), 3.64 (3H, s),
4.45 (1H, d, J ¼ 10:3 Hz), 5.19 (1H, dd, J ¼ 5:9, 9.4 Hz), 5.39
(1H, dd, J ¼ 5:5, 9.4 Hz), 6.21–6.24 (2H, m), 6.55 (1H, dd,
J ¼ 5:3, 11.0 Hz), 6.59 (1H, dd, J ¼ 5:4, 11.0 Hz), 7.24–7.26
(2H, m), 7.32–7.38 (3H, m); 13C NMR (125 MHz, CDCl3) ꢁ
41.7, 57.9, 83.8, 106.5–106.8 (m), 119.6, 122.7, 125.5, 126.3,
127.4, 128.1, 129.4, 129.8, 130.7, 131.4, 137.7 (m, d, J ¼ 252
Hz), 143.5 (m, d, J ¼ 259 Hz), 145.4 (m, d, J ¼ 252 Hz), 156.6,
166.8; Anal. Found: C, 61.23; H, 3.81; N, 3.08%. Calcd for
C23H16F5NO3: C, 61.47; H, 3.59; N, 3.12%.
2-tert-Butyl-1-azaazulene (5b): Red oil; IR (ZnSe) 2956,
1583, 1482, 1434, 1405, 1319, 1228, 1008, 929, 794, 748, 717
1
cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 1.54 (9H, s), 7.29 (1H, s),
7.57 (1H, dd, J ¼ 9:6, 9.7 Hz), 7.70 (1H, dd, J ¼ 9:6, 9.7 Hz),
7.77 (1H, dd, J ¼ 9:6, 9.9 Hz), 8.44 (1H, d, J ¼ 9:9 Hz), 8.62
(1H, d, J ¼ 9:6 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 30.4, 34.9,
110.4, 128.2, 128.8, 133.8, 134.4, 136.0, 147.5, 157.7, 182.2;
HRMS(FABþ) Found: m=z 186.1300. Calcd for C13H16N: (M +
H)þ, 186.1283.
4-(Cyclohepta-2,4,6-trienylmethyl)-1-phenylbut-1-yn-3-one
(Z)-O-Pentafluorobenzoyloxime (1o): Prepared as above in 89%
yield from 2o (2 steps); Colorless needles; mp 126–128 ꢁC; IR
(ZnSe) 3016, 2362, 2206, 1760, 1652, 1496, 1324, 1201, 1180,
2-Isopropyl-1-azaazulene (5c): Red oil; IR (ZnSe) 3365,
2960, 1720, 1583, 1481, 1438, 1334, 1012, 794, 746, 586 cmꢂ1
;
1
1089, 1002, 885, 759, 690 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ
2.25, (1H, td, J ¼ 5:6, 7.8 Hz), 3.00 (2H, d, J ¼ 7:8 Hz), 5.31
(2H, dd, J ¼ 5:6, 9.1 Hz), 6.23–6.28 (2H, m), 6.67–6.71 (2H,
m), 7.36 (2H, dd, J ¼ 7:0, 7.5 Hz), 7.43 (1H, t, J ¼ 7:5 Hz),
7.45 (2H, d, J ¼ 7:0 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 36.6,
37.3, 79.0, 104.0, 106.5–106.7 (m), 120.5, 124.1, 125.5, 128.6,
130.5, 131.2, 132.4, 137.8 (m, d, J ¼ 254 Hz), 143.6 (m, d, J ¼
259 Hz), 145.7 (m, d, J ¼ 259 Hz), 151.6, 156.4; Anal. Found:
C, 65.07; H, 3.26; N, 3.05%. Calcd for C24H14F5NO2: C, 65.02;
H, 3.18; N, 3.16%.
General Procedure for the Synthesis of 1-Azaazulenes 5. In-
to a flask containing MS 4A (363 mg) was added a solution of 2-
(cyclohepta-2,4,6-trienyl)-1-phenylethanone (Z)-O-pentafluoro-
benzoyloxime (1a) (150 mg, 0.358 mmol) in DMF (18 mL) under
an argon atmosphere; the mixture was stirred at room temperature
for 1 h. To the mixture was added Pd(dba)2 (21.2 mg, 0.036 mmol),
t-Bu3P in toluene (1 g/mL, 0.029 mL, 0.014 mmol), and triethyl-
amine (0.15 mL, 1.1 mmol). This mixture was then heated to 80 ꢁC
for 30 min. After cooling to 0 ꢁC, the mixture was filtered through a
celite pad, and water was added. Organic materials were extracted
1H NMR (500 MHz, CDCl3) ꢁ 1.49 (6H, d, 6.8 Hz), 3.45 (1H, sep-
tet, J ¼ 6:8 Hz), 7.24 (1H, s), 7.58 (1H, dd, J ¼ 9:8, 9.8 Hz), 7.70
(1H, dd, J ¼ 9:5, 9.8 Hz), 7.77 (1H, dd, J ¼ 9:3, 9.5 Hz), 8.44 (1H,
d, J ¼ 9:8 Hz), 8.59 (1H, d, J ¼ 9:3 Hz); 13C NMR (125 MHz,
CDCl3) ꢁ 22.6, 31.8, 110.7, 128.3, 129.0, 133.8, 134.2, 136.0,
147.5, 157.7, 179.6; HRMS(FABþ) Found: m=z 172.1138. Calcd
for C12H14N: (M + H)þ, 172.1126.
2-Cyclopropyl-1-azaazulene (5d): Red oil; IR (ZnSe) 3370,
3004, 1583, 1538, 1481, 1407, 1375, 1326, 1101, 1022, 933,
865, 790, 744 cmꢂ1 1H NMR (270 MHz, CDCl3) ꢁ 1.23–1.26
;
(4H, m), 2.33–2.44 (1H, m), 7.07 (1H, s), 7.48–7.55 (1H, m),
7.60–7.69 (2H, m), 8.30 (1H, d, J ¼ 9:9 Hz), 8.43–8.47 (1H, m);
13C NMR (67.5 MHz, CDCl3) ꢁ 11.9, 13.8, 110.5, 128.4, 129.1,
132.5, 132.9, 135.2, 147.4, 158.0, 176.2; Anal. Found: C, 84.88;
H, 6.68; N, 8.07%. Calcd for C12H11N: C, 85.17; H, 6.55; N,
8.28%.
2-Methyl-1-azaazulene (5e):16 Dark purple oil; 1H NMR (270
MHz, CDCl3) ꢁ 2.83 (3H, s), 7.19 (1H, s), 7.59 (1H, dd, J ¼ 9:7,
10.3 Hz), 7.67–7.82 (2H, m), 8.42 (1H, d, J ¼ 9:72 Hz), 8.55

S. Chiba et al.
Bull. Chem. Soc. Jpn., 77, No. 4 (2004)
795
(1H, d, J ¼ 9:45 Hz).
7.88 (1H, dd, J ¼ 9:6, 9.8 Hz), 7.96 (1H, dd, J ¼ 9:3, 9.8 Hz), 8.02
(1H, dd, J ¼ 9:6, 10.1 Hz), 8.06 (1H, d, J ¼ 8:5 Hz), 8.31 (1H, d,
J ¼ 8:7 Hz), 8.97 (1H, d, J ¼ 10:1 Hz), 9.03 (1H, d, J ¼ 9:3 Hz),
9.13 (1H, d, J ¼ 8:8 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 118.7,
123.0, 123.7, 124.7, 126.5, 127.1, 128.2, 128.4, 128.7, 130.3,
132.2, 135.1, 136.7, 137.2, 142.2, 157.4, 159.7.
5,6-Dihydrobenzo[g]cyclohepta[b]indole (5k0):24 Purple oil;
1H NMR (500 MHz, CDCl3) ꢁ 3.17 (2H, t, J ¼ 7:5 Hz), 3.24 (2H,
t, J ¼ 7:5 Hz), 7.32–7.41 (3H, m), 7.50 (1H, dd, J ¼ 9:4, 9.9 Hz),
7.62 (1H, dd, J ¼ 9:6, 9.9 Hz), 7.69 (1H, dd, J ¼ 9:4, 10.0 Hz),
8.26 (1H, d, J ¼ 10:0 Hz), 8.37 (1H, d, J ¼ 7:2 Hz), 8.57 (1H,
d, J ¼ 9:6 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 20.4, 29.3,
122.5, 125.4, 127.2, 127.5, 128.4, 129.0, 129.9, 131.9, 132.0,
134.4, 136.1, 139.8, 142.1, 159.4, 163.5.
2-Styryl-1-azaazulene (5f): Red powder; mp 138–139 ꢁC; IR
(ZnSe) 3374, 3023, 1957, 1830, 1670, 1625, 1587, 1461, 1332,
1214, 970, 800, 696 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 7.33
;
(1H, dd, J ¼ 7:3, 7.3 Hz), 7.41 (2H, dd, J ¼ 7:5, 7.7 Hz), 7.47
(1H, s), 7.53 (1H, d, J ¼ 16:2 Hz), 7.54–7.58 (1H, m), 7.66 (2H,
d, J ¼ 7:5 Hz), 7.70–7.74 (2H, m), 7.89 (1H, d, J ¼ 16:2 Hz),
8.41 (1H, d, J ¼ 9:8 Hz), 8.55 (1H, d, J ¼ 10:4 Hz); 13C NMR
(125 MHz, CDCl3) ꢁ 112.8, 123.5, 127.3, 128.7, 128.8, 128.9,
129.9, 134.0, 134.5, 136.2, 136.3, 147.6, 158.9, 166.0;
HRMS(FABþ) Found: m=z 232.1109. Calcd for C17H14N: (M +
H)þ, 232.1126.
2-(4-Methoxystyryl)-1-azaazulene (5g):
(ZnSe) 3355, 2929, 1729, 1625, 1600, 1509, 1440, 1251, 1172,
Red powder; IR
1
970, 825 cmꢂ1; H NMR (500 MHz, CDCl3) ꢁ 3.84 (3H, s), 6.93
Ethyl 1-Azaazulene-2-carboxylate (5l): Red oil; IR (ZnSe)
3029, 2834, 1716, 1585, 1409, 1321, 1211, 1097, 1022, 754
(2H, d, J ¼ 8:7 Hz), 7.38 (1H, d, J ¼ 16:1 Hz), 7.42 (1H, s),
7.51–7.54 (1H, m), 7.59 (2H, d, J ¼ 8:7 Hz), 7.65–7.69 (2H, m),
7.85 (1H, d, J ¼ 16:1 Hz), 8.36 (1H, d, J ¼ 9:9 Hz), 8.51–8.54
(1H, m); 13C NMR (125 MHz, CDCl3) ꢁ 55.3, 112.5, 114.3,
121.3, 128.8, 128.9, 129.6, 129.9, 133.6, 133.9, 135.7, 136.1,
147.6, 158.9, 160.2, 166.5; HRMS(FABþ) Found: m=z 262.1259.
Calcd for C18H16ON: (M + H)þ, 262.1232.
2-Phenyl-3-methyl-1-azaazulene (5h): Purple powder; mp
115–116 ꢁC; IR (ZnSe) 3353, 3052, 1577, 1465, 1417, 1334,
1184, 1120, 987, 698 cmꢂ1; H NMR (270 MHz, CDCl3) ꢁ 2.73
(3H, s), 7.42–7.61 (4H, m), 7.67 (1H, dd, J ¼ 9:3, 9.9 Hz), 7.77
(1H, dd, J ¼ 9:3, 9.7 Hz), 8.06 (2H, d, J ¼ 7:8 Hz), 8.37 (1H, d,
J ¼ 9:9 Hz), 8.63 (1H, d, J ¼ 9:7 Hz); 13C NMR (67.5 MHz,
CDCl3) ꢁ 11.1, 119.5, 127.2, 128.5, 128.7, 128.8, 129.7, 132.9,
135.2, 136.4, 136.6, 145.3, 157.3, 165.9; Anal. Found: C, 86.75;
H, 6.21; N, 6.22%. Calcd for C16H13N: C, 87.64; H, 5.98; N,
6.39%.
2,3-Diphenyl-1-azaazulene (5i): Purple powder; mp 121–122
ꢁC; IR (ZnSe) 3374, 3056, 1598, 1579, 1500, 1417, 1330, 1072,
;
1025, 700 cmꢂ1 1H NMR (270 MHz, CDCl3) ꢁ 7.33–7.57 (9H,
cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 1.50 (3H, t, J ¼ 7:1 Hz),
4.57 (2H, q, J ¼ 7:2 Hz), 7.66 (1H, dd, J ¼ 9:7, 9.8 Hz), 7.88
(1H, dd, J ¼ 9:9, 9.9 Hz), 7.99 (1H, s), 8.05 (1H, dd, J ¼ 9:8,
9.9 Hz), 8.75 (1H, d, J ¼ 9:7 Hz), 8.95 (1H, d, J ¼ 9:9 Hz);
13C NMR (125 MHz, CDCl3) ꢁ 14.5, 61.6, 116.9, 129.3, 130.1,
139.4, 140.6, 147.0, 156.2, 157.5, 164.3; HRMS(FABþ) Found:
m=z 202.0870. Calcd for C12H12O2N: (M + H)þ, 202.0868.
Ethyl Quinoline-2-carboxylate (9):25 Colorless oil; 1H NMR
(500 MHz, CDCl3) ꢁ 1.50 (3H, t, J ¼ 7:1 Hz), 4.57 (2H, d, J ¼ 7:1
Hz), 7.66 (1H, dd, J ¼ 7:9, 8.1 Hz), 7.80 (1H, dd, J ¼ 8:1, 8.5 Hz),
7.89 (1H, d, J ¼ 7:9 Hz), 8.20 (1H, dd, J ¼ 8:5 Hz), 8.31 (1H, d,
J ¼ 4:6 Hz), 8.33 (1H, d, J ¼ 4:6 Hz); 13C NMR (125 MHz,
CDCl3) ꢁ 14.4, 62.3, 121.0, 127.5, 128.5, 129.3, 130.2, 130.8,
137.2, 147.6, 148.3, 165.5.
1
Ethyl Isoquinoline-3-carboxylate (10):26
Colorless oil;
1H NMR (500 MHz, CDCl3) ꢁ 1.50 (3H, t, J ¼ 7:2 Hz), 4.55
(2H, d, J ¼ 7:2 Hz), 7.74–7.82 (2H, m), 7.99 (1H, d, J ¼ 8:2
Hz), 8.07 (1H, d, J ¼ 8:1 Hz), 8.61 (1H, s), 9.36 (1H, s); 13C NMR
(125 MHz, CDCl3) ꢁ 14.4, 61.9, 124.0, 127.7, 128.0, 129.5, 129.9,
131.1, 135.5, 141.8, 152.7, 165.8.
m), 7.69–7.86 (4H, m), 8.32 (1H, d, J ¼ 9:7 Hz), 8.72 (1H, d, J ¼
9:5 Hz); 13C NMR (67.5 MHz, CDCl3) ꢁ 125.8, 127.2, 128.3,
128.7, 128.8, 129.0, 129.5, 130.0, 130.8, 134.3, 135.0, 135.6,
136.0, 137.3, 145.7, 157.6, 164.5; HRMS(FABþ) Found: m=z
282.1295. Calcd for C21H16N: (M + H)þ, 282.1283.
1-(Cyclohepta-2,4,6-trienyl)acetonitrile (11): Pale yellow
oil; IR (ZnSe) 3018, 2925, 2242, 1523, 1498, 1423, 1402, 1326,
;
1193, 1102 cmꢂ1 1H NMR (500 MHz, CDCl3) ꢁ 2.29 (1H, td,
J ¼ 6:0, 7.2 Hz), 2.61 (2H, d, J ¼ 7:2 Hz), 5.29 (2H, dd,
J ¼ 6:0, 9.2 Hz), 6.27–6.30 (2H, m), 6.67–6.70 (2H, m); 13C NMR
(125 MHz, CDCl3) ꢁ 19.8, 35.3, 118.6, 122.8, 126.4, 131.3;
HRMS(EIþ) Found: m=z 131.0711. Calcd for C9H9N: Mþ,
131.0735.
ꢀ
ꢀ
(3R , 3aS )-2,3-Diphenyl-3,3a-dihydrocyclohepta[b]pyrrole
(4i): Yellow oil; IR (ZnSe) 3021, 2362, 1600, 1508, 1490, 1444,
1332, 1166, 1074, 991, 763, 690 cmꢂ1 1H NMR (500 MHz,
;
CDCl3) ꢁ 2.99–3.01 (1H, m), 4.59 (1H, d, J ¼ 4:7 Hz), 5.52
(1H, dd, J ¼ 3:6, 9.8 Hz), 6.12 (1H, ddd, J ¼ 2:1, 5.9, 9.8 Hz),
6.32 (1H, dd, J ¼ 5:9, 11.1 Hz), 6.54 (1H, dd, J ¼ 6:3, 11.1 Hz),
6.65 (1H, d, J ¼ 6:3 Hz), 7.17–7.35 (8H, m), 7.84 (2H, d, J ¼
7:2 Hz); 13C NMR (125 MHz, CDCl3) ꢁ 51.6, 62.4, 116.2, 123.7,
126.5, 127.0, 127.3, 128.4, 128.8, 128.9, 129.1, 129.7, 130.9,
133.2, 142.3, 155.2, 178.6; HRMS(FABþ) Found: m=z 284.1410.
Calcd for C21H18N: (M + H)þ, 284.1439.
2-Pentafluorophenyl-1-phenylacetylene (13):27
Colorless
1
needles; H NMR (500 MHz, CDCl3) ꢁ 7.37–7.43 (3H, m), 7.57–
7.59 (2H, m); 13C NMR (125 MHz, CDCl3) ꢁ 73.0, 100.2–100.3
(m), 101.5, 121.5, 128.5, 129.6, 131.9, 137.7 (m, d, J ¼ 248 Hz),
141.4 (m, d, J ¼ 256 Hz), 147.2 (m, d, J ¼ 257 Hz); 19F NMR
(470 MHz, CDCl3) ꢁ ꢂ0:13 to ꢂ0:06 (2F, m), 8.97 (1F, t, J ¼
18:8 Hz), 25.70–25.78 (2F, m).
2-Ethyl-3-methyl-1-azaazulene (5j): Purple oil; IR (ZnSe)
3355, 2967, 1668, 1581, 1479, 1430, 1324, 1062, 937 cmꢂ1
;
1H NMR (500 MHz, CDCl3) ꢁ 1.44 (3H, t, J ¼ 7:6 Hz), 2.50
(3H, s), 3.11 (2H, q, J ¼ 7:6 Hz), 7.52 (1H, dd, J ¼ 9:7, 9.8
Hz), 7.52 (1H, dd, J ¼ 9:8, 9.9 Hz), 7.71 (1 H, dd, J ¼ 9:8, 9.9
Hz), 8.25 (1H, d, J ¼ 9:9 Hz), 8.48 (1H, d, J ¼ 9:7 Hz); 13C NMR
(125 MHz, CDCl3) ꢁ 9.3, 13.4, 24.1, 119.7, 126.8, 128.1, 131.6,
133.4, 135.8, 143.9, 157.1, 173.4; HRMS(FABþ) Found: m=z
172.1142. Calcd for C12H14N: (M + H)þ, 172.1126.
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1
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Fig. 2. Dihydro-1-azaazulenes.
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