4
Tetrahedron
8.
Karpov, S. V.; Kayukov, Ya. S.; Grigor’ev, A. A.; Tafeenko
V. A. Tetrahedron Letters. 2015, 56, 1732.
Supplementary Material
9.
Rabjohn, N. Org. React. (N. Y.). 1976 , 24 , 261
Contains 1H, 13C NMR data for compounds 3, 4 and
ORTEP image of 3d.
10. CCDC 1960984 contain the supplementary crystallographic
data for 5с. These data can be obtained free of charge from the
Cambridge
11. Synthesis of dimethyl 3-acyl(aroyl)-1,2-dicyanocyclopropane-
1,2-dicarboxylates (General procedure).
Crystallographic
Data
Centre
via
2
Aryl(heteroaryl)methylketone (0.1 mol) was oxidized to
corresponding aryl(heteroaryl)gyoxale via described method6
using DMSO-NaBr-H2SO4 mixture. When the reaction is
finished, the formed yellow-orange reaction mass was cooled to
r.t. and dissolved in 100 ml of ethanol with methyl cyanoacetate
(19.8 g, 0.2 mol). To the resulting solution was added dropwise
a concentrated solution of KOH in ethanol under stirring until
the reaction mass becomes alkaline. The mixture was stirred for
15 min then neutralized by addition of 20% H2SO4 and cooled
to r.t. Bromine (16.0 g, 0.1 mol) was added dropwise to the
reaction mass with vigorous stirring. After decoloration of
bromine, the mixture was poured into 700 ml of distilled water
and stay for 30 min. The pale-brown oil which formed was
separated from the solution and dissolved in 80 ml of boiling
EtOH. After cooling, the formed white solid precipitate was
filtered, washed by cold ethanol and dried in air. If necessary,
cyclopropanes 2 could be purificated via reprecipitation from a
benzene solution by hexane or heptane.
Synthesis of ADCP 1 was realized via described method8 using
potassium acetate as a base.
12. Synthesis of dimethyl 6-amino-4-aroyl(heteroaroyl)-2-oxo-2H-
pyran-3,5-dicarboxylates 3 (General procedure).
ADCP (0.12 mmol) was dissolved in 5 ml of mixture water-
acetic acid (3:1) with heating. To the resulting solution under
stirring was added dropwise 15% H2SO4 (2 ml), then the
mixture was heated at 70-80°C until it discolored (3-5 min).
After cooling, water (6 ml) was added to the reaction mass and
stay for 4-5 hours. The resulting white solid precipitate was
filtered and recrystallized from methanol.
Notes: 1) The reaction mass should not be stayed overnight or
longer due to resinification. 2) In the case using water instead
of mixture water-acetic acid and caring out the reaction at r.t.,
the yellow precipitate of unpured pirilium salts 5 will form
immediately. These compounds are unstable when heated, in air
and daylight so we were not able to purify them using
recrystallization or column chromatigraphy. For the XRD
analysis, the single crystal of 5c was obtained by evaporation of
acetonitrile solution in dark at -18°C.
Dimethyl 6-amino-4-benzoyl-2-oxo-2H-pyran-3,5-
dicarboxylate (3a).
Compound 3a: white solid, mp 171 - 172 ºС. 1H NMR (500.13
MHz, DMSO-d6): δ 3.34 (3H, s, CH3), 3.40 (3H, s, CH3), 7.49
(2H, t, 3J = 7.7 Hz, Ar), 7.58 (2H, t, 3J = 7.4 Hz, Ar), 7.83 (1H,
3
d, J = 7.2 Hz, Ar), 9.05 (1H, s, NH2), 9.79 (1H, s, NH2). 13C
NMR (121 MHz, DMSO-d6): δ 51.2, 51.3, 86.5, 98.1, 127.7,
128.4, 136.5, 154.6, 162.9, 163.5, 163.6, 166.0, 192.2. MS (EI,
70 eV): m/z (%) 331 (24) [M]+, 105 (100) [ArCO]+, 77 (61)
[Ar]+. Anal. Calcd for C16H13NO7: C, 58.01; H, 3.96; N, 4.23.
Found: C, 56.82; H, 4.03; N, 4.13.
13. Synthesis of methyl 6-amino-4- aroyl(heteroaroyl)-3-cyano-2-
oxo-2H-pyran-5-carboxylates 4 (General procedure).
ADCP (0.12 mmol) was dissolved in
6 ml of boiling
concentrated (56%) hydroiodic acid. After cooling, water (6 ml)
was added to the reaction mass and stay for 2 hours. The
resulting white solid precipitate was filtered and recrystallized
from acetic acid.
Methyl 6-amino-4-benzoyl-3-cyano-2-oxo-2H-pyran-5-
carboxylate (4a).
Compound 4a: white solid, mp 262 - 263 ºС. 1H NMR (500.13
MHz, DMSO-d6): δ 3.43 (3H, s, CH3), 7.57 (2H, t, 3J = 7.7 Hz,
Ar), 7.71 (1H, t, 3J = 7.3 Hz, Ar), 7.97 (2H, d, 3J = 7.2 Hz, Ar),
9.31 (1H, NH2), 10.22 (1H, NH2). 13C NMR (121 MHz,
DMSO-d6): δ 52.1, 80.1, 88.0, 115.0, 129.1, 129.3, 134.5,
134.8, 156.7, 163.1, 165.1, 166.3, 191.4. . MS (EI, 70 eV): m/z
(%) 298 (24) [M]+, 105 (100) [ArCO]+, 77 (61) [Ar]+. Anal.
Calcd for C15H10N2O5: C, 60.41; H, 3.38; N, 9.39. Found: C,
59.85; H, 3.44; N, 9.23.