2ꢀNitroꢀ2,3,4,5,6ꢀhexahydrobenzofuranꢀ4ꢀones
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 10, October, 2009
2037
(sodium metal (0.04 g, 1.5 mmol) in 5 mL of anhydrous methaꢀ
nol), 1,1ꢀdinitroꢀ2ꢀphenylethene (1a) (0.29 g, 1.5 mmol) was
added at 16—18 °C with stirring. The reaction mixture was stirred
for 2 h at this temperature, then poured onto ground ice, and
acidified with glacial acetic acid to neutral pH. The precipitate
was filtered off. Compound 2a was obtained in a yield of 0.31 g
(68%), m.p. 140—142 °C (from C6H6—MeOH, 10 : 1). A mixture
of this sample with the compound obtained by procedure A did
not show melting point depression.
2ꢀ[2,2ꢀDinitroꢀ1ꢀ(4ꢀchlorophenyl)ethyl]cyclohexaneꢀ1,3ꢀdiꢀ
one (2b). A. This was obtained from compound 1b and diꢀ
hydroresorcinol according to the procedure A for the synthesis of
diketone 2a. The yield was 0.25 g (49%), colorless crystals, m.p.
153—154 °C (from C6H6—MeOH, 10 : 1). Found (%): С, 49.64;
Н, 4.13; N, 8.01. С14Н13СlN2O6. Calculated (%): С, 49.34;
Н, 3.82; N, 8.22. IR (Nujol), ν/cm–1: 1582, 1380 (NO2).
B. Starting from compound 1b and dihydroresorcinol, comꢀ
pound 2b was obtained according to the procedure B for
the synthesis of diketone 2a in a yield of 0.35 g (68%), m.p.
153—155 °C (from C6H6—MeOH, 10 : 1). A mixture of this
sample with the compound obtained by procedure A did not
show melting point depression.
2ꢀ[2,2ꢀDinitroꢀ1ꢀ(4ꢀtolyl)ethyl]cyclohexaneꢀ1,3ꢀdione (2c).
A. This was obtained from compound 1c and dihydroresorcinol
according to the procedure A for the synthesis of diketone 2a.
The yield was 0.18 g (38%), colorless crystals, m.p. 161—162 °C
(from C6H6—MeOH, 10 : 1). Found (%): С, 56.24; Н, 5.24;
N, 8.72. С15Н16N2О6. Calculated (%): С, 56.25; Н, 5.00; N, 8.75.
IR (Nujol), ν/cm–1: 1575, 1379 (NO2).
B. Starting from compound 1c and dihydroresorcinol, comꢀ
pound 2c was obtained according to the procedure B for the
synthesis of diketone 2a in a yield of 0.43 g (89%), m.p.
161—162 °C (from C6H6—MeOH, 10 : 1). A mixture of this
sample with the compound obtained by procedure A did not
show melting point depression.
2ꢀ(2,2ꢀDinitroꢀ1ꢀphenylethyl)ꢀ5,5ꢀdimethylcyclohexaneꢀ1,3ꢀ
dione (2d). A. This was obtained from compound 1a and diꢀ
medone according to the procedure A for the synthesis of diꢀ
ketone 2a. The yield was 0.46 g (91%), colorless crystals, m.p.
141—143 °C (from C6H6—MeOH, 10 : 1). Found (%): С, 57.55;
Н, 5.61; N, 8.36. С16Н18N2О6. Calculated (%): С, 57.49;
Н, 5.39; N, 8.38. IR (Nujol), ν/cm–1: 1584, 1377 (NO2).
B. Starting from compound 1a and dimedone, compound 2d
was obtained according to the procedure B for the synthesis of
diketone 2a in a yield of 0.47 g (93%), m.p. 141—142 °C (from
C6H6—MeOH, 10 : 1). A mixture of this sample with the comꢀ
pound obtained by procedure A did not show melting point deꢀ
pression.
2ꢀ[2,2ꢀDinitroꢀ1ꢀ(4ꢀchlorophenyl)ethyl]ꢀ5,5ꢀdimethylcycloꢀ
hexaneꢀ1,3ꢀdione (2e). A. This was obtained from compound 1b
and dimedone according to the procedure A for the synthesis of
diketone 2a. The yield was 0.42 g (75%), colorless crystals, m.p.
112—114 °C (from C6H6—MeOH, 10 : 1). Found (%): С, 52.32;
Н, 4.69; N, 7.74. С16Н17ClN2О6. Calculated (%): С, 52.10;
Н, 4.61; N, 7.60. IR (Nujol), ν/cm–1: 1570, 1373 (NO2).
B. Starting from compound 1b and dimedone, compound 2e
was obtained according to the procedure B for the synthesis of
diketone 2a in a yield of 0.42 g (75%), m.p. 112—113 °C
(from C6H6—MeOH, 10 : 1). A mixture of this sample with the
compound obtained by procedure A did not show melting point
depression.
2ꢀ[2,2ꢀDinitroꢀ1ꢀ(4ꢀtolyl)ethyl]ꢀ5,5ꢀdimethylcyclohexaneꢀ
1,3ꢀdione (2f). A. This was obtained from compound 1c and
dimedone according to the procedure A for the synthesis of diꢀ
ketone 2a. The yield was 0.32 g (62%), colorless crystals, m.p.
101—102 °C (from C6H6—MeOH, 10 : 1). Found (%): С, 58.47;
Н, 5.83; N, 7.73. С17Н20N2О5. Calculated (%): С, 58.62;
Н, 5.75; N, 8.04. IR (Nujol), ν/cm–1: 1576, 1376 (NO2).
B. Starting from compound 1c and dimedone, compound 2f
was obtained according to the procedure B for the synthesis of
diketone 2a in a yield of 0.40 g (78%), m.p. 100—101 °C (from
C6H6—MeOH, 10 : 1). A mixture of this sample with the comꢀ
pound obtained by procedure A did not show melting point deꢀ
pression.
2ꢀNitroꢀ3ꢀphenylꢀ2,3,4,5,6,7ꢀhexahydrobenzofuranꢀ4ꢀone
(3a). Triethylamine (0.14 mL, 0.10 g, 1 mmol) was added to
a suspension of 2ꢀ(2,2ꢀdinitroꢀ1ꢀphenylethyl)cyclohexaneꢀ1,3ꢀ
dione (2a) (0.31 g, 1 mmol) in 10 mL of anhydrous methanol.
The reaction mixture was stirred for 48 h at 16—18 °C, then
poured into a Petri dish. The oily substance produced was trituꢀ
rated with methanol. The yield of the title compound was 0.18 g
(71%), colorless crystals, m.p. 96—97 °C (from hexane). A mixꢀ
ture with the authentic sample obtained as described earlier8 did
not show melting point depression.
2ꢀNitroꢀ3ꢀ(4ꢀchlorophenyl)ꢀ2,3,4,5,6,7ꢀhexahydrobenzoꢀ
furanꢀ4ꢀone (3b). This was obtained analogously from compound
2b. Yield 0.10 g (33%), colorless crystals, m.p. 95—96 °C (from
hexane). A mixture with the authentic sample obtained as deꢀ
scribed earlier7 did not show melting point depression.
2ꢀNitroꢀ3ꢀ(4ꢀtolyl)ꢀ2,3,4,5,6,7ꢀhexahydrobenzofuranꢀ4ꢀone
(3c). A. This was obtained analogously from compound 2c. Yield
0.12 g (45%), colorless crystals, m.p. 92—93 °C (from hexane).
Found (%): С, 65.77; Н, 5.79; N, 4.96. С15Н15NО4. Calculatꢀ
ed (%): С, 65.93; Н, 5.49; N, 5.13.
B. Triethylamine (0.21 mL, 0.15 g, 1.5 mmol) was added to
a hot solution of 1ꢀbromoꢀ1ꢀnitroꢀ2ꢀ(4ꢀtolyl)ethene (1c) (0.36 g,
1.5 mmol) and dihydroresorcinol (0.16 g, 1.5 mmol) in 14 mL of
anhydrous benzene. The reaction mixture was boiled for 2 h,
triethylamine hydrobromide was filtered off, then the reacꢀ
tion mixture was poured into a Petri dish. A slightly tarred
substance that formed was triturated with a small amount of
ethanol. The yield of the title compound was 0.21 g (51%), m.p.
91—92 °C (from hexane). A mixture of this sample with the
compound obtained by procedure A did not show melting point
depression.
6,6ꢀDimethylꢀ2ꢀnitroꢀ3ꢀphenylꢀ2,3,4,5,6,7ꢀhexahydrobenzoꢀ
furanꢀ4ꢀone (3d). This was obtained from compound 2d analoꢀ
gously to the synthesis of product 3a. The oily substance formed
was triturated with ethanol. Yield 0.22 g (75%), colorless crysꢀ
tals, m.p. 98—100 °C (from hexane). A mixture with the authenꢀ
tic sample obtained as described earlier8 did not show melting
point depression.
6,6ꢀDimethylꢀ2ꢀnitroꢀ3ꢀ(4ꢀchlorophenyl)ꢀ2,3,4,5,6,7ꢀhexaꢀ
hydrobenzofuranꢀ4ꢀone (3e). This was obtained from compound
2e analogously to the synthesis of product 3a. Yield 0.25 g (78%),
colorless crystals, m.p. 138—139 °C (from hexane). A mixture
with the authentic sample obtained as described earlier7 did not
show melting point depression.
6,6ꢀDimethylꢀ2ꢀnitroꢀ3ꢀ(4ꢀtolyl)ꢀ2,3,4,5,6,7ꢀhexahydroꢀ
benzofuranꢀ4ꢀone (3f). A. This was obtained from compound 2f
analogously to the synthesis product 3a. Yield 0.23 g (75%),
colorless crystals, m.p. 137—138 °C (from hexane). Found (%):