2
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Russ.Chem.Bull., Int.Ed., Vol. 57, No. 1, January, 2008
Aksenov et al.
1
The first step includes the reaction of the protonated
6.59. H NMR (CDCl ), δ: 1.48 (t, 3 H, OCH Me, J = 7.0 Hz);
3 2
2
.57 (s, 3 H, COMe); 4.27 (q, 2 H, OCH Me, J = 7.0 Hz); 7.48,
.00 (both d, 1 H each, H(4), H(3), J = 9.1 Hz); 7.38 (dd, 1 H, H(7),
J = 7.3 Hz, J = 8.0 Hz); 7.50 (dd, 1 H, H(6), J = 7.3 Hz, J = 8.0 Hz);
.65 (d, 1 H, H(5), J = 8.0 Hz); 7.90 (d, 1 H, H(8), J = 8.0 Hz).
ꢀEthoxynaphthaleneꢀ1,8ꢀdicarbaldehyde (4a). The yield was
.144 g (63%). Yellow crystals with m.p. 163—164 °C (from
octane, subl.). Found (%): C, 73.72; H, 5.18. C H O . Calcuꢀ
lated (%): C, 73.67; H, 5.30. H NMR (CDCl ), δ: 1.52 (t, 3 H,
triazines with ether 1 to form dihydrotriazines 5, the
hydrolysis of which leads to compounds 3a,b. The ring
opening in compounds 5 upon treatment with acid leads
to cations 6, the intramolecular electrophilic substituꢀ
tion in which results in the formation of azaphenalenes 7.
The hydrolysis of the latter afforded compounds 4
2
8
7
2
0
14
12
3
1
(
Scheme 2).
3
In conclusion, the method allows one to accomplish
CH , J = 7.0 Hz); 4.35 (q, 2 H, CH , J = 7.0 Hz); 7.27, 8.20 (both
3
2
monoacylation and regioselective diacetylation (diꢀ
formylation) in positions 1 and 8 of the naphthalene ring.
d, 1 H each, H(3), H(4), J = 9.5 Hz); 7.78 (dd, 1 H, H(6), J =
7
.3 Hz, J = 8.4 Hz); 8.11 (d, 1 H, H(5), J = 8.4 Hz); 8.47 (d, 1 H,
H(7), J = 7.3 Hz); 10.84, 12.13 (both s, 1 H each, C(8)CHO,
C(1)CHO).
Experimental
1
,8ꢀDiacetylꢀ2ꢀethoxynaphthalene (4b). The yield was
.202 g (79%). Yellow crystals with m.p. 159—161 °C (from octane).
Found (%): C, 75.13; H, 6.18. C H O . Calculated (%): C, 74.98;
0
1H NMR spectra were recorded on a Bruker WPꢀ200
16
16 3
1
H, 6.29. H NMR (CDCl ), δ: 1.48 (t, 3 H, OCH Me, J = 7.0 Hz);
spectrometer with the use of SiMe as the internal standard. Melting
3
2
4
3
.07, 3.15 (both s, 3 H each, C(6)COMe, C(1)COMe); 4.14 (q, 2
points were determined in the sealed capillary tubes on a PTP
device and were not corrected. 1,3,5ꢀTriazine is a commercial
reagent (Aldrich). 2,4,6ꢀTrimethylꢀ1,3,5ꢀtriazine and 2ꢀethoxyꢀ
H, OCH Me, J = 7.0 Hz); 6.73, 7.71 (both d, 1 H each, H(3), H(4),
2
4
J = 10.0 Hz); 7.64 (dd, 1 H, H(6), J = 7.3 Hz, J = 8.4 Hz); 7.89 (d,
5
1
H, H(5), J = 8.4 Hz); 8.31 (d, 1 H, H(7), J = 7.3 Hz).
naphthalene were obtained by known procedures.
Acylnaphthalenes 3 and 4 (general procedure). A mixture of
2
ꢀethoxynaphthalene (1) (0.172 g, 1 mmol), the corresponding
References
triazine (1.5 mmol), and PPA (3—4 g) was vigorously stirred under
the following conditions: 2 h at 40—45 °C (for the synthesis of
compound 3a); 2 h at 55—60 °C (3b); 3 h at 55—60 °C (4a); 3 h at
1
. A. V. Aksenov, I. V. Borovlev, A. S. Lyakhovnenko, I. V.
Aksenova, Khim. Geterotsikl. Soedin., 2007, 629 [Chem.
Heterocycl. Compd., 2007, 49 (Engl. Transl.)].
. I. V. Borovlev, A. V. Aksenov, I. V. Aksenova, S. I. Pisareneko,
Izv. Akad. Nauk, Ser. Khim., 2007, 2275 [Russ. Chem. Bull., Int.
Ed., 2007, 56, 2354.
100—110 °C (4b). The reaction mixture was cooled, poured in cold
water (30 mL) under stirring, extracted with ethyl acetate (3×50
mL). The solvent was evaporated for isolation of compounds 4, the
reaction mixture was made basic by addition of aqueous ammonia.
Ethanol (products 3a,b) or octane (products 4a,b) were used for the
recrystallization.
2
3
4
5
. F. Uhlig, Angew. Chem., 1954, 66, 435.
. F. C. Schaefer, G. A. Peters, J. Org. Chem., 1961, 26, 2778.
. N. Donaldson, Khimiya i tekhnologiya soedinenii naftalinovogo
ryada [Chemistry and Technology of Compounds of Naphthalene
Series], Goskhimizdat, Moscow, 1963, p. 403 (in Russian).
. Organic Syntheses, V. 20, J. Wiley and Sons, New York, 1940,
pp. 11.
2ꢀEthoxyꢀ1ꢀnaphthaldehyde (3a). The yield was 0.162 g (81%).
Yellow needles with m.p. 111—112 °C (from ethanol) (cf. Ref. 6:
m.p. 111—112 °C). A mixture with authentic sample did not give a
depression of the melting point. Found (%): C, 78.14; H, 5.98.
C H O . Calculated (%): C, 77.98; H, 6.04.
6
13
12
2
1
ꢀAcetylꢀ2ꢀethoxynaphthalene (3b). The yield was 0.182 g
(85%). Yellow crystals with m.p. 63—65 °C (from ethanol). Found
Received June 27, 2007;
(
%): C, 78.61; H, 6.51. C H O . Calculated (%): C, 78.48; H,
in revised form November 6, 2007
14
14
2