SYNTHESIS OF 1-ARYL-3-OXO-1,2,3,4-TETRAHYDROBENZO[f]QUINOLINES
1169
caused apparently by the influence of a carbonyl
group in the -position with respect to NH group [7].
5% solutions in deuterated dimethyl sulfoxide,
internal reference TMS. 13C NMR spectra were taken
on Tesla BS-587 A at operating frequency 20 MHz.
Mass spectra were measured on Chromass GC/MS
Hewlett Packard 5890/5972 instrument, column
HP-5MS (70 eV), solvent dichloromethane. UV
spectra of compounds in ethanol solution (c 1
1
A specific feature of H NMR spectra of tetra-
hydrobenzo[f]quinolines XVI XXVII (Table 3)
consists in a downfield shift of the signal from H1
proton as compared to the usual position of methine
proton signals in the cyclic compounds [8].
4
1
10 mol ) were recorded on spectrophotometer
Specord UV-Vis.
In the 1H NMR spectra of compounds XVI
XXVII appears a group of multiplet signals from the
aromatic protons of naphthalene ring in the region
7.10 8.49 ppm in some cases overlapping with the
signals of benzene ring that are observed as a
multiplet in the 6.31 7.490 ppm range, or as a
multiplet and singlet or doublet depending on the
substituents position in the benzene ring. All the
spectra of compounds synthesized contain a broaden-
ed singlet at 10.25 10.45 ppm belonging to the amino
group proton. Alongside the above signals the follow-
ing resonances are observed: in the spectra of com-
pounds XIX, XXI a singlet at 3.70 3.87 ppm, in the
spectrum of compound XXII two singlets at 3.78 and
3.98, and in the spectrum of compound XVIII a
quartet centered at 3.91 ppm from the protons of
methyl group in the substituent. The singlet from the
hydroxy group proton appears in the spectra of com-
pounds XVI XIX at 9.25, 9.25, 9.28, and 8.70 ppm
respectively. Note that the aryl substituent at C1 atom
is in a pseudoequatorial position. It is evidenced by
the value of coupling constant between atoms C1 Ha
(4.21 5.29 ppm) and C2 Ha (3.00 3.37 ppm) equal
to 7.5 Hz. Such decrease in the standard value of the
2,2-Dimethyl-1,3-dioxane-4,6-dione (II) (Mel-
drum,s acid). The condensation of malonic acid and
acetone in the presence of acetic anhydride was
performed by procedure [12]. mp 99 100 C (from
alcohol).
1-Aryl-3-oxo-1,2,3,4-tetrahydrobenzo[f]quino-
lines XVI XXVII. A mixture of 0.01 mol of an
appropriate benzaldehyde III XV, 0.01 mol of
2-naphthylamine, and 0,01 mol of Meldrum,s acid
was boiled in 20 30 ml of ethanol for 0.5 2 h. The
separated precipitate was filtered off, washed with
ether to remove the unreacted initial compounds, and
crystallized from a mixture ethanol benzene, 2: 1
(compounds XVI, XVI were crystallized from acetic
acid) to obtain the reaction product of a purity no less
than 95%.
In preparation of compound XXV the reaction
mixture after boiling for 1 h was evaporated to 2/3 of
its volume, and on cooling the reaction product was
precipitated with dioxane. The crystals were filtered
off and recrystallized from dioxane.
3
coupling constant Ja,a ( 11 Hz) results from
The authors are grateful to Dr. Chem. Sci V. A. Ral-
dugin, head of the laboratory of wood chemistry at
Novosibirsk Institute of Organic Chemistry, Siberian
Division, Russian Academy of Sciences, for register-
ing and interpretation of the double-resonance
1H NMR spectra.
considerable distortion of the bond angles in the
cyclohexene ring [9] caused by the presence therein
of a lactam group and by conjugation with the
naphthalene ring.
In contrast to [10], in reaction of 1-naphthylamine
with benzaldehydes and Meldrum’s acid we failed to
separate products similar to those obtained from
2-naphthylamine, benzaldehydes, and Meldrum,s
acid, but only tarry substances of unidentified nature.
We also did not succeed in alkylating compounds
XVI XXVII along procedure from [11]. The latter
fact as we believe confirms that the compounds
synthesized have amide structure.
REFERENCES
1. Kozlov, N.G., Basalaeva, L.I., and Tychin-
skaya, L.Yu., Zh. Org. Khim., 2000, vol. 36, no. 9,
pp. 1399 1403.
2. Levy, G.C., Lichter, R.L., and Nelson, G.L.,
Carbon-13 Nuclear Magnetic Resonance Spectro-
scopy, New York: John Wiley & Sons, 1980.
3. Strods, A.Ya., Kampare, R.B., Lielbriedis, I.E., and
Neiland, O.Ya., Khim. Geterotsikl. Soed., 1977,
no. 7, pp. 973 976.
EXPERIMENTAL
IR spectra were registered on spectrometer
Protege-460 (Nicolet). 1H NMR spectra were
4. Strods, A.Ya., Tsiekure, V.P., Kampars, V.E.,
Lielbriedis, I.E., and Neiland, O.Ya., Khim. Getero-
tsikl. Soed., 1978, no. 11, pp. 1369 1372.
recorded on spectrometers Tesla BS-567
A
(100 MHz) and Bruker AC-300 (300 MHz) from 2
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 38 No. 8 2002
Kozlov
