Reactions of aliphatic diazo compounds: VI. Reactions of diazomethane and ethyl diazoacetate with (E)-2-arylmethylene-1,2,3,4-tetrahydronaphthalen-1-ones

Article abstract of DOI:10.1023/B:RUJO.0000036064.74236.19

Diazomethane and ethyl diazoacetate add to (E)-2-arylmethylene-1,2,3,4- tetrahydronaphthalen-1-ones in a regio- and stereoselective fashion, yielding the corresponding 4'-aryl-1,2,3,4,4',5'-hexahydro-3'H-naphthalene-2-spiro-3'- pyrazol-1-ones. The products formed by addition of ethyl diazoacetate undergo isomerization into 4,5-dihydro-1H-pyrazole derivatives.

Full text of DOI:10.1023/B:RUJO.0000036064.74236.19

Russian Journal of Organic Chemistry, Vol. 40, No. 4, 2004, pp. 470–473. Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 4, 2004,
pp. 501–504.
Original Russian Text Copyright © 2004 by Molchanov, Korotkov, Kostikov.
Reactions of Aliphatic Diazo Compounds:
VI.* Reactions of Diazomethane and Ethyl Diazoacetate
with (E)-2-Arylmethylene-1,2,3,4-tetrahydronaphthalen-1-ones
A. P. Molchanov, V. S. Korotkov, and R. R. Kostikov
St. Petersburg State University, Universitetskii pr. 26, St. Petersburg, 198504, Russia
Rceived October 1, 2003
Abstract—Diazomethane and ethyl diazoacetate add to (E)-2-arylmethylene-1,2,3,4-tetrahydronaphthalen-1-
ones in a regio- and stereoselective fashion, yielding the corresponding 4'-aryl-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-ones. The products formed by addition of ethyl diazoacetate undergo
isomerization into 4,5-dihydro-1H-pyrazole derivatives.
We previously showed that 1,3-dipolar cycloaddi-
tion of ethyl diazoacetate to 1,3-diaryl-2-propen-
1-ones occurs with high regioselectivity to afford
isomeric 4,5-dihydro-1H-pyrazoles [2]. Reactions of
diazomethane with α,β-unsaturated cyclic ketones
having an exocyclic double bond, e.g., 2-aryl-
methylene-3-phenyl-1-indanones, 3-arylmethylene-
flavanones, etc. [3], were studied by many authors. It
was found that the process is regioselective and that
the products are spiro-4,5-dihydro-3H-pyrazoles. How-
ever, there are no published data on reactions of such
compounds with diazoacetic acid esters.
NMR spectra contained signals from the 4'-H proton in
the pyrazole ring as a doublet of doublets at δ 3.82–
4.31 ppm and signals from two 5'-H protons in the
δ region of 5.0 ppm. According to our previous data
and those reported in [4], the phenyl group in com-
pound IIa is arranged trans with respect to the
carbonyl group.
Reactions of tetralones Ia–Id, If, and Ii with ethyl
diazoacetate in toluene at 90–95°C in 120 h afforded
up to 56% of the corresponding ethyl 4'-aryl-1-oxo-
1,2,3,4,-4',5'-hexahydro-1'H-naphthalene-2-spiro-5'-
pyrazole-3'-carboxylates IIIa–IIIf (Scheme 2).
We have studied reactions of diazomethane and
ethyl diazoacetate with (E)-2-arylmethylene-1,2,3,4-
tetrahydronaphthalen-1-ones Ia–Ih. Diazomethane re-
acted with compounds Ia–Ih in diethyl ether at 0°C to
afford 37–69% of the corresponding 4'-aryl-1,2,3,4,-
4',5'-hexahydro-3'H-naphthalene-2-spiro-3'-pyrazol-1-
ones IIa–IIh (Scheme 1). The structure of products
IIa–IIh was determined on the basis of their spectral
parameters and elemental compositions. The IR spe-
The structure of compounds IIIa–IIIf was derived
from their elemental analyses and spectral data. The IR
spectra of IIIa–IIIf contained an absorption band at
1
3370 cm–1 due to NH group. In the H NMR spectra
we observed a singlet at δ 9.25–9.52 ppm (NH),
a singlet at δ 4.57–4.92 ppm from 4'-H, and also
signals from aromatic protons and protons of the ethyl
and –CH2CH2– groups. The signal from the aromatic
ortho protons appears as a broadened singlet at room
temperature; on heating to 50°C it is converted into
1
ctra of IIa–IIh lacked NH absorption, while their H
Scheme 1.
O
O
N
N
CH2N2
H
Ar
Ar
Ia–Ih
IIa–IIh
Ar = Ph (a), 4-MeC6H4 (b), 4-ClC6H4 (c), 4-BrC6H4 (d), 4-MeOC6H4 (e), 3-NO2C6H4 (f), 3-MeOC6H4 (g), 2-ClC6H4 (h).
* For communication V, see [1].
1070-4280/04/4004-0470 © 2004 MAIK “Nauka/Interperiodica”

REACTIONS OF ALIPHATIC DIAZO COMPOUNDS: VI.
471
Scheme 2.
O
O
N
N
N
HN
N2CHCOOEt
H
H
COOEt
COOEt
Ia–Id, If, Ii
Ar
Ar
IIIa–IIIh
Ii, Ar = 4-NO2C6H4; III, Ar= Ph (a), 4-MeC6H4 (b), 4-ClC6H4 (c), 4-BrC6H4 (d), 4-NO2C6H4 (e), 3-NO2C6H4 (f).
a doublet with J = 8.0 Hz. This patten may be inter-
preted in terms of restrictied rotation of the aryl group
in molecules IIIa–IIIf due to spatial interaction with
the –C3H2C4H2– group, which is possible only when
the aromatic and carbonyl groups are arranged trans.
mixture was left overnight. The solvent was
evaporated, and the residue was recrystallized from
ethanol.
4'-Phenyl-1,2,3,4,4',5'-hexahydro-3'H-naphtha-
lene-2-spiro-3'-pyrazol-1-one (IIa). Yield 54%,
mp 70–72°C. IR spectrum, ν, cm–1: 920, 1300, 1455,
1
The H–1H NOESY spectrum of compound IIIb
displayed interaction between the C3H2 protons,
protons in the ortho position of the aromatic ring, and
NH proton, whereas no interaction between NH and
4'-H was observed. The 13C NMR spectrum of IIIa
contained signals at δC 14.9 (CH3), 26.1 (CH2), 29.2
(CH2), 54.0 (CH), 60.8 (CH2), 74.1 (C), 162.5 (CO),
and 194.1 ppm (CO), as well as signals from the
aromatic carbon atoms. The signal from C3' (where the
ester group is attached) is located at δ 130–145 ppm.
Thus the reactions of diazomethane and ethyl di-
azoacetate with 2-arylmethylenetetrahydronaphthalen-
1-ones I are regio- and stereoselective, and the nucleo-
philic carbon atom in the diazo compound adds at
the unsaturated carbon atom in the β-position with
respect to the carbonyl group, i.e., in keeping with
the Auvers rule.
1
1600 s, 1680 v.s, 2940, 3030. H NMR spectrum, δ,
ppm (J, Hz): 1.73 m (1H), 2.10 d.t (1H, J = 14, 5),
2.77 d.t (1H, J = 17, 5), 3.23 m (1H), 3.90 d.d (1H, J =
7, 6), 4.98 d. d (1H, J = 18, 7), 5.00 d. d (1H, J = 18,
6), 7.05 d (1H, J = 7), 7.19–7.33 (3H), 7.36–7.48 (2H),
7.65 t (1H, J = 8), 7.95 d (1H, J = 8). Found %:
C 78.04; H 5.87; N 9.87. C18H16N2O. Calculated, %:
C 78.24; H 5.84; N 10.14.
4'-(4-Methylphenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IIb). Yield
60%, mp 119–121°C. IR spectrum, ν, cm–1: 920, 1030,
1120, 1160, 1245, 1300, 1455, 1600 s, 1690 v.s, 2930,
1
3040. H NMR spectrum (CDCl3), δ, ppm (J, Hz):
1.93 m (1H), 2.20 d. t (1H, J = 14, 5), 2.33 s (3H),
2.88 d.t (1H, J = 17, 5), 3.52 m (1H), 3.88 d.d (1H, J =
7, 5), 5.03 d.d (1H, J = 18, 7), 5.05 d. d (1H, J = 18, 5),
6.85 d (2H, J = 8), 7.10 d (2H, J = 8), 7.30 d (1H,
J = 8), 7.38 d.d (1H, J = 8, 7), 7.56 d.d (1H, J = 8, 7),
8.08 d (1H, J = 8). Found %: C 78.39; H 6.27; N 9.26.
C19H18N2O. Calculated, %: C 78.59; H 6.25; N 9.65.
EXPERIMENTAL
The IR spectra were recorded on a UR-20 spectro-
1
photometer from 2% solutions in CHCl3. The H and
13C NMR spectra were recorded on a Bruker DPX-300
instrument at 300.13 and 75.47 MHz, respectively,
from solutions in DMSO-d6. The reaction mixtures
were analyzed, and the purity of the products was
checked, by TLC on Silufol UV-254 plates. Initial
2-arylmethylene-1,2,3,4-tetrahydronaphthalen-1-ones
Ia–Ii were synthesized as described in [5].
4'-(4-Chlorophenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IIc). Yield
60%, mp 87–89°C. IR spectrum, ν, cm–1: 920 s, 1020,
1100 s, 1160, 1290, 1300, 1355, 1450, 1490 s, 1600 s,
1680 v.s, 2860, 2940, 3030. 1H NMR spectrum, δ, ppm
(J, Hz): 1.73 m (1H), 2.08 d. t (1H, J = 14, 5), 2.81 d.t
(1H, J = 17, 5), 3.26 m (1H), 3.94 d.d (1H, J = 7, 6),
4.97 d.d (1H, J = 18, 7), 5.01 d.d (1H, J = 18, 6),
7.09 d (2H, J = 8), 7.35 d (2H, J = 8), 7.40 d (1H,
J = 7), 7.43 d.d (1H, J = 8, 7), 7.65 d.d (1H, J = 8, 7),
7.96 d (1H, J = 8). Found, %: C 69.66; H 4.86; N 8.84.
C18H15ClN2O. Calculated, %: C 69.57; H 4.86; N 9.01.
4'-Aryl-1,2,3,4,4',5'-hexahydro-3'H-naphtha-
lene-2-spiro-3'-pyrazol-1-ones IIa–IIh (general pro-
cedure). A solution of diazomethane in diethyl ether,
prepared from 5 g (49 mmol) of N-nitrosomethylurea,
was added to a cold solution of 4 mmol of the
corresponding 2-arylmethylene-1,2,3,4-tetrahydro-
naphthalen-1-one Ia–Ih in 10 ml of benzene, and the
4'-(4-Bromophenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IId). Yield
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 4 2004

MOLCHANOV et al.
472
47%, mp 124°C. IR spectrum, ν, cm–1: 920, 1020,
43%, mp 103°C. IR spectrum, ν, cm–1: 920, 1045,
1160, 1300 s, 1455, 1480, 1600 s, 1690 s, 2940, 3035.
1H NMR spectrum, δ, ppm (J, Hz): 1.78 m (1H),
1.91 d.t (1H, J = 14, 5), 2.82 d.t (1H, J = 17, 5), 3.40 m
(1H), 4.31 d.d (1H, J = 9, 3), 4.98 d.d (1H, J = 18, 9),
5.24 d.d (1H, J = 18, 3), 7.05 d.d (1H, J = 8, 2),
7.32 t.d (1H, J = 8, 2), 7.37– 7.48 (3H), 7.66 t (1H,
J = 8), 7.96 d (1H, J = 8). Found, %: C 69.42; H 5.04;
N 8.77. C18H15ClN2O. Calculated, %: C 69.57; H 4.86;
N 9.01.
1080, 1120, 1160, 1245, 1290, 1300, 1450, 1490 s,
1
1600 s, 1690 v.s, 2940, 3040. H NMR spectrum
(CDCl3), δ, ppm (J, Hz): 1.89 m (1H), 2.12 d. t (1H,
J = 14, 5), 2.90 d. t (1H, J = 17, 5), 3.59 m (1H), 3.93 t
(1H, J = 7), 5.04 d (2H, J = 7), 6.85 d (2H, J = 8),
7.31 d (1H, J = 8), 7.38 d.d (1H, J = 8, 7), 7.58 d.d
(1H, J = 8, 7), 8.08 d (1H, J = 8). Found, %: C 61.09;
H 4.37; N 7.72. C18H15BrN2O. Calculated, %: C 60.86;
H 4.26; N 7.89.
Ethyl 4'-aryl-1-oxo-1,2,3,4,4',5'-hexahydro-1'H-
naphthalene-2-spiro-5'-pyrazole-3'-carboxylates
IIIa–IIIf (general procedure). Ethyl diazoacetate, 2 g
(18 mmol), was added to a solution of 3.7 mmol of the
corresponding 2-arylmethylene-1,2,3,4-tetrahydro-
naphthalen-1-one in 30 ml of anhydrous toluene, and
the mixture was heated for 120 h at 90–95°C (the
progress of the reaction was monitored by TLC). The
solvent was distilled off under reduced pressure, and
the residue was recrystallized from a 1:8 ethyl
acetate–hexane mixture.
4'-(4-Bromophenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IIe). Yield
67%, mp 138°C. IR spectrum, ν, cm–1: 910, 1040,
1260, 1300, 1455, 1520, 1600 s, 1690 s, 2830, 2940,
3040. 1H NMR spectrum, δ, ppm (J, Hz): 1.75 m (1H),
2.14 d.t (1H, J = 14, 5), 2.79 d.t (1H, J = 17, 5), 3.19 m
(1H), 3.71 s (3H), 3.82 t (1H, J = 7), 4.92 d (1H, J =
7), 6.84 d (2H, J = 8), 6.95 d (2H, J = 8), 7.39 d (1H,
J = 8), 7.42 t (1H, J = 8), 7.64 t (1H, J = 8), 7.96 d
(1H, J = 8). Found, %: C 74.49; H 5.88; N 8.88.
C19H18N2O2. Calculated, %: C 74.49; H 5.92; N 9.14.
Ethyl 1-oxo-4'-phenyl-1,2,3,4,4',5'-hexahydro-
1'H-naphthalene-2-spiro-5'-pyrazole-3'-carboxylate
(IIIa). Yield 34%, mp 148– 149°C. IR spectrum, ν,
cm–1: 1070, 1115, 1135, 1300, 1420, 1480, 1500,
4'-(4-Nitrophenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IIf). Yield
69%, mp 80–82°C. IR spectrum, ν, cm–1: 915, 1020,
1090, 1160, 1300, 1350 s, 1450, 1540 s, 1600, 1690 s,
2950, 3040. 1H NMR spectrum, δ, ppm (J, Hz): 1.75 m
(1H), 2.05 d.t (1H, J = 14, 5). 2.85 d.t (1H, J = 17, 5),
3.30 m (1H), 4.16 d.d (1H, J = 8, 6), 5.05 d.d (1H, J =
18, 8), 5.12 d.d (1H, J = 18, 6), 7.40 d (1H, J = 8),
7.44 t (1H, J = 8), 7.53 d (1H, J = 8), 7.60 t (1H, J =
8), 7.66 t (1H, J = 8), 7.95 s (1H), 7.98 d (1H, J = 8),
8.12 d (1H, J = 8). Found, %: C 67.45; H 4.69;
N 12.99. C18H15N3O3. Calculated, %: C 67.28; H 4.71;
N 13.08.
1
1690 s, 2940, 3040, 3370. H NMR spectrum, δ, ppm
(J, Hz): 1.15 t (3H, J = 7), 1.69 d.t (1H, J = 14, 5),
1.82 m (1H), 2.74 d.t (1H, J = 18, 5), 2.91 m (1H),
4.01 m (2H), 4.65 s (1H), 7.08 br.s (2H), 7.26–
7.38 m (4H), 7.41 t (1H, J = 8), 7.60 t.d (1H, J = 8, 1),
7.96 d (1H, J = 8), 9.25 s (1H). 13C NMR spectrum
(DMSO-d6), δ, ppm: 14.9 (CH3), 26.1 (CH2), 29.2
(CH2), 54.0 (CH), 60.8 (CH2), 74.1 (C), 127.8 (CH),
128.3 (CH), 128.6 (CH), 129.4 (CH), 129.8 (CH),
130.7 (C), 134.9 (CH), 136.9 (C), 143.6 (C), 144.5 (C),
162.5 (CO), 194.1 (CO). Found, %: C 72.31; H 5.76%;
N 7.95. C21H20N2O3. Calculated, %: C 72.40; H 5.79;
N 8.04.
4'-(4-Methoxyphenyl)-1,2,3,4,4',5'-hexahydro-
3'H-naphthalene-2-spiro-3'-pyrazol-1-one (IIg).
Yield 38%, mp 107°C. IR spectrum, ν, cm–1: 905,
1060, 1160, 1300, 1455, 1490, 1600 s, 1690 s, 2840,
2940, 3040. 1H NMR spectrum, δ, ppm (J, Hz): 1.79 m
(1H), 2.12 d.t (1H, J = 14, 5), 2.81 d.t (1H, J = 17, 5),
3.24 m (1H), 3.70 s (3H), 3.88 d.d (1H, J = 8, 6),
4.97 d.d (1H, J = 18, 8), 5.01 d.d (1H, J = 18, 6),
6.58 d (1H, J = 8), 6.64 d (1H, J = 3), 6.82 d. d (1H,
J = 8, 3), 7.21 t (1H, J = 8), 7.39 d (1H, J = 8), 7.42 t
(1H, J = 8), 7.65 t (1H, J = 8), 7.98 d (1H, J = 8).
Found, %: C 74.52; H 5.91; N 9.26. C19H18N2O2.
Calculated, %: C 74.49; H 5.92; N 9.14.
Ethyl 4'-(4-methylphenyl)-1-oxo-1,2,3,4,4',5'-
hexahydro-1'H-naphthalene-2-spiro-5'-pyrazole-3'-
carboxylate (IIIb). Yield 40%, mp 185–186°C. IR
spectrum, ν, cm–1: 1070, 1115, 1250, 1300, 1420,
1600, 1700 s, 2930, 3040, 3370. 1H NMR spectrum, δ,
ppm (J, Hz): 1.10 t (3H, J = 7), 1.75 m (2H), 2.29 s
(3H), 2.76 m (1H), 2.88 m (1H), 4.02 m (2H), 4.57 s
(1H), 6.97 br.s (2H), 7.15 d (2H, J = 8), 7.30 d (1H,
J = 8), 7.41 t (1H, J = 8), 7.58 t (1H, J = 8), 7.95 d
(1H, J = 8), 9.30 s (1H). Found, %: C 72.64; H 6.05;
N 7.29. C22H22N2O3. Calculated, %: C 72.91; H 6.12;
N 7.73.
4'-(2-Chlorophenyl)-1,2,3,4,4',5'-hexahydro-3'H-
naphthalene-2-spiro-3'-pyrazol-1-one (IIh). Yield
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 4 2004

REACTIONS OF ALIPHATIC DIAZO COMPOUNDS: VI.
473
8, 1), 7.97 d (1H, J = 8), 8.23 d (2H, J = 9), 9.52 s
(1H). Found, %: C 64.41; H 4.84; N 10.70.
C21H19N3O5. Calculated, %: C 64.12; H 4.87; N 10.68.
Ethyl 4'-(4-chlorophenyl)-1-oxo-1,2,3,4,4',5'-
hexahydro-1'H-naphthalene-2-spiro-5'-pyrazole-3'-
carboxylate (IIIc). Yield 54%, mp 209–210°C. IR
spectrum, ν, cm–1: 1020, 1070, 1095, 1115, 1130,
1250, 1300, 1430, 1490, 1600, 1690 s, 3040, 3370.
1H NMR spectrum, δ, ppm (J, Hz): 1.12 t (3H, J = 7),
1.68 d.t (1H, J = 14, 5), 1.81 m (1H), 2.75 d.t (1H,
J = 17, 5), 2.92 m (1H), 4.01 m (2H), 4.68 s (1H),
7.11 br.s (2H), 7.31 d (1H, J = 8), 7.37–7.45 (3H),
7.59 t (1H, J = 8), 7.95 d (1H, J = 8), 9.37 s (1H).
Found, %: C 65.84; H 5.10; N 7.22. C21H19ClN2O3.
Calculated, %: C 65.88; H 5.00; N 7.32.
Ethyl 4'-(3-nitrophenyl)-1-oxo-1,2,3,4,4',5'-hexa-
hydro-1'H-naphthalene-2-spiro-5'-pyrazole-3'-car-
boxylate (IIIf). Yield 27%, mp 143°C. IR spectrum, ν,
cm–1: 1070, 1110, 1240 s, 1300, 1350 s, 1470, 1535,
1
1600, 1700 s, 3365. H NMR spectrum, δ, ppm
(J, Hz): 1.12 t (3H, J = 7), 1.64 m (1H), 1.88 m (1H),
2.76 m (1H), 2.94 m (1H), 4.06 m (2H), 4.92 s (1H),
7.31 d (1H, J = 8), 7.41 t (1H, J = 8), 7.59 t (1H, J =
7), 7.62 br.s (1H), 7.67 t (1H, J = 8), 7.97 d (1H, J =
8), 8.17 d (1H, J = 7), 9.52 s (1H). Found, %: C 64.06;
H 5.07; N 10.52. C21H19N3O5. Calculated, %: C 64.12;
H 4.87; N 10.68.
Ethyl 4'-(4-bromophenyl)-1-oxo-1,2,3,4,4',5'-
hexahydro-1'H-naphthalene-2-spiro-5'-pyrazole-3'-
carboxylate (IIId). Yield 44%, mp 204°C. IR spec-
trum, ν, cm–1: 1015, 1075, 1110, 1255, 1300, 1420,
1
1600, 1700 s, 3365. H NMR spectrum, δ, ppm
REFERENCES
(J, Hz): 1.11 t (3H, J = 7), 1.66 d.t (1H, J = 13, 5),
1.82 m (1H), 2.74 d.t (1H, J = 17, 5), 2.94 m (1H),
4.05 m (2H), 4.67 s (1H), 7.05 br.s (2H), 7.31 d (1H,
J = 8), 7.42 t (1H, J = 8), 7.54 d (2H, J = 8), 7.61 t
(1H, J = 8), 7.96 d (1H, J = 8), 9.36 s (1H). Found, %:
C 58.91; H 4.51; N 6.31. C21H19BrN2O3. Calculated,
%: C 59.03; H 4.48, N 6.56.
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Ethyl 4'-(4-nitrophenyl)-1-oxo-1,2,3,4,4',5'-hexa-
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1
boxylate (IIIe). Yield 56%, mp 203°C. H NMR
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(1H, J = 13, 5), 1.84 m (1H), 2.75 d.t (1H, J = 17, 5),
2.94 m (1H), 4.08 m (2H), 4.90 s (1H), 7.32 d (1H, J =
8), 7.40 br.s (2H), 7.42 t (1H, J = 8), 7.60 t.d (1H, J =
4. Toth, G., Szollősy, A., Levai, A., and Kotovych, G.,
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RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 40 No. 4 2004