Reactions of polyhalonitrosoarenes with phenylacetylene

Article abstract of DOI:10.1007/s11172-010-0098-z

Phenylacetylene reacts with polyhalonitrosoarenes to give two isomers of 1-phenyl-1,2bis(2,4,6-trihalophenylnitrono)ethane.

Full text of DOI:10.1007/s11172-010-0098-z

Russian Chemical Bulletin, International Edition, Vol. 59, No. 2, pp. 441—445, February, 2010
441
Reactions of polyhalonitrosoarenes with phenylacetylene
L. M. Gornostaev,a N. V. Geets,a E. A. Bocharova,a G. A. Stashina,b S. I. Firgang,b and A. F. Smol´yakovc
aV. P. Astaf´ev Krasnoyarsk State Pedagogical University,
89 ul. A. Lebedevoi, 660049 Krasnoyarsk, Russian Federation.
Eꢀmail: gornostaev@kspu.ru
bN. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences,
47 Leninsky prosp., 119991 Moscow, Russian Federation.
Fax: +7 (499) 137 2966. Eꢀmail: galina_stashina@chemicalꢀblock.com
cA. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
28 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (499) 135 0176. Eꢀmail: fedya@xrlab.ineos.ac.ru
Phenylacetylene reacts with polyhalonitrosoarenes to give two isomers of 1ꢀphenylꢀ1,2ꢀ
bis(2,4,6ꢀtrihalophenylnitrono)ethane.
Key words: polyhalonitrosoarenes, phenylacetylene, 1ꢀphenylꢀ1,2ꢀbis(2,4,6ꢀtrihaloꢀ
phenylnitrono)ethanes, addition.
Scheme 2
It is known that the pathway of reactions of nitrosoareꢀ
nes with alkynes depends on the structure of the latter. For
instance, a reaction of nitrosobenzene 1a with tolan gives
bisnitrone 2a (see Ref. 1) (Scheme 1). With other internal
alkynes, the reaction proceeds similarly.
Scheme 1
A reaction of nitrosobenzene with phenylacetylene
passes through the formation of unstable 1ꢀhydroxyꢀ3ꢀ
phenylindole 3, its Oꢀmethylation leading to more stable
1ꢀmethoxyꢀ3ꢀphenylindole 4 (see Ref. 2), and oxidative
cyclodimerization into cisꢀ1,10ꢀdiazaꢀ9,20ꢀdioxadibenzoꢀ
[b,g]tetracyclo[7.2.1.04,1106,10]dodecane 5 (see Ref. 3)
(Scheme 2).
A singleꢀstep synthesis of Nꢀmethoxyindoles from
alkynes and nitrosoarenes (PhH, K2CO3, Me2SO4) is simꢀ
pler than the previous methods.2
nient to carry out these reactions in benzene at 45—50 °C.
After nitrosoarenes were completely consumed, the reacꢀ
tion mixtures were cooled to 10—15 °C, which resulted in
crystallization of pale yellow products 6b—e. The filtrates
contained compounds 6b—e and 7b—e (TLC data); prodꢀ
ucts 7b,c were isolated by column chromatography
(Scheme 3). In boiling toluene, products 7b,c were transꢀ
formed into compounds 6b,c, respectively.
In our continued systematic investigations of reacꢀ
tions of 2,6ꢀdihalonitrosobenzenes with unsaturated comꢀ
pounds,4 we studied reactions of polyhalonitrosoarenes
1b—e with phenylacetylene. It should be noted that the
reactions in various solvents (PhH, PhMe, and AcOH)
yield the same products. It proved preparatively conveꢀ
Structures 6 and 7 were determined by physicochemiꢀ
cal methods. According to 1H NMR data, products 6b—e
and 7b,c are formed from two moles of nitrosoarene and
one mole of phenylacetylene (Table 1). Interestingly, the
singlet signals of one proton in all the four compounds
6b—e appear in the same range (δ 8.25—8.35). At the
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 431—435, February, 2010.
1066ꢀ5285/10/5902ꢀ0441 © 2010 Springer Science+Business Media, Inc.

442
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 2, February, 2010
Gornostaev et al.
Scheme 3
1, 6, 7
X
Y
b
Br
F
c
Br
Br
d
Br
Cl
e
Cl
Cl
same time, in the spectra of compounds 7b,c, the singlet
signals of one proton are shifted upfield compared to the
signals for compounds 6b,c by ~0.6 ppm. Structures 6c
and 7c were ultimately identified by Xꢀray diffraction
(Figs 1, 2; Tables 2—4).
Both compounds show torsion about the single C(1)—C(2)
bond; the dihedral angles between two planar fragments
N(1)O(1)C(3)C(1)C(15) and N(2)O(2)C(9)C(2) are 24.5°
O(1)
Br(3)
Compounds 6 and 7 are configurational isomers beꢀ
longing to a rare type of structures with the acyclic fragꢀ
ment (O)N=C—C=N(O). According to the Cambridge
Crystallographic Data (version 2007), no structurally charꢀ
acterized compounds containing such a fragment have
been documented. Isomers 6c and 7c differ in the relative
positions of the aromatic substituent C(3)—C(8) and the
O(1) atom about the C(1)=N(1) bond. The torsion angle
O(1)—N(1)—C(1)—C(2) is 7.4° in 6c and 174.4° in 7c.
C(8)
Br(4)
C(7)
N(1)
С(2)
C(6)
С(11)
Br(5)
С(3)
Br(1)
N(2)
С(9)
С(10)
Br(2)
С(1)
C(5)
С(12)
С(13)
С(15)
С(20)
С(19)
С(18)
С(14)
О(2)
С(16)
С(17)
Br(6)
Fig. 1. Molecular structure of compound 6c with atomic thermal
displacement ellipsoids (50% probability).
Table 1. 1H NMR spectra of 1ꢀphenylꢀ1,2ꢀbis(2,4,6ꢀtrihaloꢀ
phenylnitrono)ethanes 6b—e and 7b,c
Br(2)
Comꢀ
pound
δ (J/Hz)
CH=N H(3´), H(5´), HPh(3), HPh(4),
HPh(2),
HPh(6)
C(6)
С(5)
C(7)
H(3″), H(5″)
HPh(5)
6b
8.25 (s)
7.56 (d),
7.39 (d),
J = 8*
7.24—7.27
(m)
7.18—7.20
(m)
Br(4)
С(4)
C(8)
Br(5)
С(11)
Br(1)
С(12)
Br(3)
6c
6d
6e
7b
8.35 (s)
8.36 (s)
8.24 (s)
7.71 (s)
7.96 (s),
8.11 (s)
7.86 (s),
8.01 (s)
7.43 (s),
7.45 (s)
7.77 (d),
7.89 (d),
J = 8*
7.30—7.31
(m)
7.29—7.34
(m)
7.27—7.30
(m)
7.45—7.51
(m)
7.49—7.51
(m)
7.50—7.51
(m)
7.23—7.25
(m)
7.74—7.76
(m)
С(3)
С(10)
N(2)
С(9)
N(1)
С(13)
С(2)
O(1)
С(1)
С(15)
С(14)
О(2)
С(20)
С(19)
Br(6)
С(16)
С(17)
7c
7.79 (s)
8.02(s),
8.13 (s)
7.46—7.49
(m)
7.73—7.75
(m)
С(18)
* The coupling constant of the protons is due to the orthoꢀF
Fig. 2. Molecular structure of compound 7c with atomic thermal
atoms.
displacement ellipsoids (50% probability).

1,2ꢀBis(2,4,6ꢀtrihalophenylnitrono)ethanes
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 2, February, 2010
443
Table 2. Selected bond lengths (d) in comꢀ
pounds 6c and 7c
Table 3. Selected bond angles (ω) in compounds
6c and 7c
Bond
d/Å
Bond angle
ω/deg
6с
7с
6с
7с
O(1)—N(1)
O(2)—N(2)
N(1)—C(1)
N(1)—C(3)
N(2)—C(2)
N(2)—C(9)
C(1)—C(2)
1.299(5)
1.274(5)
1.332(6)
1.449(6)
1.316(6)
1.447(6)
1.421(6)
1.282(5)
1.277(5)
1.331(6)
1.454(6)
1.299(6)
1.452(6)
1.438(7)
O(1)—N(1)—C(1)
O(1)—N(1)—C(3)
C(1)—N(1)—C(3)
O(2)—N(2)—C(2)
O(2)—N(2)—C(9)
C(2)—N(2)—C(9)
N(1)—C(1)—C(2)
N(1)—C(1)—C(15)
C(2)—C(1)—C(15)
N(2)—C(2)—C(1)
124.4(4)
125.6(4)
113.3(4)
121.1(4)
124.7(4)
114.2(4)
121.1(4)
118.5(4)
118.5(4)
122.9(5)
123.8(5)
113.9(4)
121.5(4)
126.7(4)
114.4(4)
118.8(4)
115.5(4)
120.3(4)
123.8(4)
123.5(5)
and 35.4° in 6c and 7c, respectively. In both structures,
the brominated aromatic rings are nearly perpendicular to
the corresponding planar fragments (the dihedral angles
are 80.9°—86.9°). At the same time, the angles between
the plane of the phenyl substituent at the C(1) atom and
the plane N(1)C(1)C(2) noticeably differ in compounds
6c and 7c (46.1° and 77.3°, respectively), which is probaꢀ
bly due to the different positions of the bulky 2,4,6ꢀtribroꢀ
mophenyl substituent at the N(1) atom.
Thus, isomers 6c and 7c differ in the positions of the
phenyl substituent and the O atom relative to the C=N
bond. Note that the Nꢀoxide fragment in isomer 6c apꢀ
proaches the aliphatic H atom. Apparently, the anisotroꢀ
pic effect of the Nꢀoxide fragment is responsible for the
downfield shifts of the signals for the aliphatic proton in
1ꢀphenylꢀ1,2ꢀbis(2,4,6ꢀtrihalophenylnitrono)ethanes 6b—e.
The mass spectra of compounds 6b,c and 7b,c show no
molecular ion peaks because of their high molecular massꢀ
es. The only fundamental difference between the mass
spectra of these compounds is that the spectra of comꢀ
pounds 7b,c contain intense peaks with m/z 105, probably
due to the phenacylium ion. The formation of phenacyliꢀ
um ions in the fragmentation of the molecular ions of
compounds 7b,c can result from a possible migration of
the O atom to the aliphatic C atom because of a shorter
distance between the Nꢀoxide and phenyl fragments in
these products.
The formation of hydroxyindole derivatives in reactions
of nitrosoarenes with phenylacetylene seems to involve
[3+2] cycloaddition; this is possible when at least one orthoꢀ
position in nitrosoarene is not substituted2,5 (see Scheme 2).
In nitrosoarenes 1b—e, both orthoꢀpositions are occuꢀ
pied by halogen atoms and the formation of 1ꢀphenylꢀ1,2ꢀ
bis(2,4,6ꢀtrihalophenylnitrono)ethanes 6 and 7 probably
results from a sequence of reactions (Scheme 4) passing
through intermediate carbene 8 or carbocation 9.
Scheme 4
6, 7
X
Y
b
Br
F
c
Br
Br
d
Br
Cl
e
Cl
Cl

444
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 2, February, 2010
Gornostaev et al.
Table 4. Selected torsion angles (ϕ) in compounds 6c
and 7c
Table 5. Yields and physicochemical properties of the 1ꢀphenylꢀ
1,2ꢀbis(2,4,6ꢀtrihalophenylnitrono)ethanes obtained
Torsion angle
ϕ/deg
Comꢀ Tm/°C
pound
Found
Molecular
formula
Yield
(%)
(%)
H
Calculated
6с
7с
C
N
O(1)—N(1)—C(1)—C(2)
C(3)—N(1)—C(1)—C(2)
O(1)—N(1)—C(1)—C(15)
C(3)—N(1)—C(1)—C(15)
O(2)—N(2)—C(2)—C(1)
C(9)—N(2)—C(2)—C(1)
N(1)—C(1)—C(2)—N(2)
C(15)—C(1)—C(2)—N(2)
O(1)—N(1)—C(3)—C(4)
C(1)—N(1)—C(3)—C(4)
O(2)—N(2)—C(9)—C(10)
C(2)—N(2)—C(9)—C(10)
N(1)—C(1)—C(15)—C(16)
C(2)—C(1)—C(15)—C(16)
7.4(6)
–167.0(4)
–179.7(4)
5.8(7)
–174.4(4)
7.2(7)
6b
6c
216—217 35.90 4.21 1.53 C20H10N2O2Br4F2 60
35.90 4.20 1.30
2.3(7)
205—207 30.38 3.54 1.27
30.40 3.50 1.10
C
20H10N2O2Br6
54
–176.1(4)
4.2(8)
6.9(8)
–169.3(4)
–170.0(4)
17.4(7)
–176.1(5)
–150.3(5)
33.1(8)
6d
6e
7b
7c
216—217 34.68 4.07 1.70
34.23 3.99 1.42
202—203 45.52 4.80 1.85 C20H10N2O2Cl6
45.89 5.35 1.91
C
20H10N2O2Br4Cl2 50
61
9
–89.4(5)
85.6(6)
79.1(5)
–102.3(6)
95.9(6)
188—190 35.80 4.47 1.59
35.90 4.20 1.30
C
20H10N2O2Br4F2
84.3(6)
–99.0(6)
–101.0(6)
71.3(7)
–83.8(7)
–132.4(5)
44.1(7)
178—180 30.30 3.74 1.49
30.40 3.50 1.10
C
20H10N2O2Br6
7
Xꢀray diffraction analysis of compounds 6c and 7c. Selected
Hence, we discovered a novel pathway in reactions of
nitrosoarenes with phenylacetylene.
crystallographic parameters and the data collection and refineꢀ
ment statistics for compounds 6c and 7c are given in Table 6.
Reflection intensities were collected on Bruker SMART 1000
CCD8 and Bruker SMART APEX II9 diffractometers for comꢀ
Experimental
Table 6. Crystallographic parameters and the data collection and
refinement statistics for compounds 6c and 7c
1
H NMR spectra were recorded on a Bruker DRX instruꢀ
ment (500 MHz) in DMSOꢀd6 with Me4Si as the internal stanꢀ
dard. The course of the reactions was monitored, and the purity
of the compounds obtained was checked, by TLC on Silufol
UVꢀ254 plates. Melting points were measured on a Boetius hotꢀ
stage microscope.
Parameter
6c
7c
Molecular formula
Molecular mass
Crystal system
Space group
a/Å
b/Å
c/Å
α/deg
β/deg
C20H10Br6N2O2 C20H10Br6N2O2
789.76
Triclinic
P–1
789.76
Monoclinic
P21/c
The starting nitrosoarenes 1b—e were prepared according to
known procedures.6,7
1ꢀPhenylꢀ1,2ꢀbis(2,4,6ꢀtrihalophenylnitrono)ethanes (6b—e).
Phenylacetylene (0.55 mL, 0.005 mol) was added to a solution of
2,4,6ꢀtrihalonitrosobenzene 1b—e (0.01 mol) in benzene (20 mL).
The reaction mixture was heated at 50 °C for 3 h. The reaction
products began to crystallize even in the hot solution. On coolꢀ
ing to 10—15 °C, compounds 6b—e were filtered off and recrysꢀ
tallized from benzene.
1ꢀPhenylꢀ1,2ꢀbis(2,4,6ꢀtrihalophenylnitrono)ethanes (7b,c).
After the isolation of products 6b,c, the filtrates were chromatoꢀ
graphed on alumina (Brockmann activity II) in benzene. The
first and second yellow fractions were collected. An additional
crop (3—5%) of compounds 6b,c was obtained from the first
fraction. Compounds 7b,c were isolated from the second fracꢀ
tion. Compounds 6b,c and 7b,c were recrystallized from benꢀ
zene and benzene—heptane (1 : 1), respectively.
8.731(1)
11.899(1)
12.099(1)
110.197(2)
94.847(2)
96.915(2)
1160.3(2)
2
8.8167(6)
12.0317(9)
21.693(2)
90
97.238(2)
90
γ/deg
3
V/Å
2282.8(3)
4
Z
dcalc/g cm–3
2θmax/deg
μ/cm–1
2.261
2.298
56
56
104.01
105.73
Tmin/Tmax
Number of independent
0.223/0.624
5509 (0.0500)
0.202/0.661
5500 (0.0840)
reflections (Rint
)
R1 (on F for reflections
with I > 2σ(I))
wR2 (on F2 for all
reflections)
0.0388 (3069)
0.0936
0.0434 (3136)
0.0952
Isomerization of product 7c into product 6c. A solution of
compound 7c (0.3 g) in toluene (15 mL) was refluxed until the
starting compound was completely consumed. On cooling,
product 6c was isolated as described above. The yield was
0.16 g (53%).
Number of parameters
refined
271
271
Yields and physicochemical constants of compounds 6b—e
and 7b,c are given in Table 5.
GOOF
0.953
1.004

1,2ꢀBis(2,4,6ꢀtrihalophenylnitrono)ethanes
Russ.Chem.Bull., Int.Ed., Vol. 59, No. 2, February, 2010
445
pounds 6c and 7c, respectively (graphite monochromator,
λ(MoꢀKα) = 0.71073 Å, ω scan mode, T = 296 K). An absorpꢀ
tion correction was applied semiempirically with the SADABS
program.10 The structures were solved by the direct methods and
3. J. Iball, W. D. S. Motherwell, J. J. S. Pollock, J. M. Tedder,
Chem. Commun., 1968, 365.
4. L. M. Gornostaev, N. V. Geets, E. A. Bocharova, G. A.
Stashina, S. I. Firgang, Izv. Akad. Nauk, Ser. Khim., 2007,
130 [Russ. Chem. Bull., Int. Ed., 2007, 56, 137].
5. A. Penoni, J. Volkmann, K. M. Nicholas, Org. Lett., 2002,
4, 699.
6. R. R. Holmes, R. P. Bayer, J. Am. Chem. Soc., 1960, 82, 3454.
7. L. M. Gornostaev, E. A. Bocharova, N. V. Geets, Zh. Org.
Khim., 2006, 42, 1310 [Russ. J. Org. Chem. (Engl. Transl.),
2006, 42].
8. SMART V5.051 and SAINT V5.00, Area Detector Control and
Integration Software, 1998, Bruker AXS Inc., Madison,
WIꢀ53719, USA.
9. APEX II Software Package, 2005, Bruker AXS Inc., 5465,
East Cheryl Parkway, Madison, WIꢀ53719, USA.
10. G. M. Sheldrick, SADABS, 1997, Bruker AXS Inc., Madiꢀ
son, WIꢀ53719, USA.
refined by the fullꢀmatrix leastꢀsquares method on F2 in the
hkl
anisotropic approximation for all nonꢀhydrogen atoms. All hyꢀ
drogen atoms were located geometrically and refined using
a riding model. All calculations were performed with the SHELXTL
program package.11 The comprehensive tables of atomic coordiꢀ
nates, bond lengths, bond angles, and anisotropic thermal paꢀ
rameters have been deposited with the Cambridge Crystalloꢀ
graphic Data Center.
This work was financially supported by the Krasnoꢀ
yarsk Regional Science Foundation (Grant 18G059) and
the V. P. Astaf´ev Krasnoyarsk State Pedagogical Univerꢀ
sity (Grant 04ꢀ08ꢀ1/NSh).
11. G. M. Sheldrick, SHELXTLꢀ97, Version 5.10, 1997, Bruker
AXS Inc., Madison, WIꢀ53719, USA.
References
1. L. Alessandri, Gazz. Chim. Ital., 1922, 52, 194; 1924, 54, 438.
2. A. Penoni, G. Palmisano, G. Broggini, A. Kadowaki, K. M.
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Received July 24, 2008;
in revised form October 22, 2009