NEW SYNTHETIC METHOD FOR PREPARATION OF FUNCTIONALLY SUBSTITUTED
2133
methoxymethyl)benzene 4a as colorless crystals
melting at 53°C (mp 53°C [13]). Н NMR spectrum
(CDCl3), δ, ppm: 3.13 s (12Н, OMe), 5.23 s (2Н,
СНO2), 7.26 s (4Н, С6Н4). 13С NMR spectrum (CDCl3),
δС, ppm: 52.1 (OMe), 102.4 (CHO2), 126.6 (СНAr),
138.1 (СAr).
Reaction of 1,4-bis(dibromomethyl)benzene (1d)
with trialkyl orthoformates (a ratio of 1.0 : 4.2). a. A
mixture of 15 g (0.0355 mol) of tetrabromide 1d,
15.82 g (0.1491 mol) of compound 2, and 0.48 g
(0.00355 mol) of zinc chloride was heated at 80°C for
2 h. The reaction mixture was distilled in a high
vacuum to give 6.05 g (76%) of compound 4a as
colorless crystals melting at 53°C (mp 53°C [13]) and
bp 107°C (0.1 mmHg) {bp 105–110°C (1.0 mmHg )
1
Reaction of methyl 4-(dibromomethyl)benzene-
carboxylate (1b) with trimethyl orthoformate (2) (a
ratio of 1 : 4). A mixture of 0.63 g (0.002 mol) of
compound 1b, 0.85 g (0.008 mol) of trimethyl ortho-
formate, and 0.03 g (0.0002 mol) of zinc chloride was
heated at 80°C for 2 h. Extraction with isooctane
provided methyl 4-(dimethoxymethyl)benzenecarboxylate
1
[11], bp 138–139°C (9 mmHg) [13]}. Н NMR spec-
3
trum (CDCl3), δ, ppm: 1.17 t (12Н, OCH2Me, JHH
=
7.0 Hz), 3.49 q (8H, OCH2, 3JHH = 7.0 Hz), 5.44 s (2Н,
СНO2), 7.37 s (4Н, С6Н4).
1
4c as a colorless oil [9–11]. Yield 0.34 g (81%). Н
b. A mixture of 15 g (0.0355 mol) of tetrabromide
1d, 1.22 g (0.1491 mol) of compound 2, and 0.48 g
(0.00355 mol) of zinc chloride was heated at 80°C for
4.5 h. The reaction mixture was distilled in a high
vacuum to give 6.8 g (68%) of 1,4-bis(diethoxy-
methyl)benzene 4b as colorless liquid, bp 119–120°C
(0.1 mmHg ) {bp 107–108°C (0.001 mmHg) [12]}. 1Н
NMR spectrum (CDCl3), δ, ppm: 1.17 t (12Н,
NMR spectrum (CDCl3), δ, ppm: 3.21 s (6Н, OMe),
3.84 s (3Н, COОMe), 5.35 s (1Н, СНO2), 7.43 and
3
7.94 d (4Н, С6Н4, JHH = 8.2 Hz). 13С NMR spectrum
(CDCl3), δС, ppm: 51.9 (COOMe), 52.2 (OMe), 101.8
(CHO2), 126.8, 127.0, 129.5, 129.5 (СНAr), 130.1,
142.8 (СAr), 166.3 (CO).
Reaction of methyl 4-(dibromomethyl)benzene-
carboxylate (1b) with triethyl orthoformate (2) (a
ratio of 1.0 : 2.6). A mixture of 1.5 g (0.0049 mol) of
compound 1b, 1.9 g (0.0128 mol) of triethyl
orthoformate 2, and 0.07 g (0.00049 mol) of zinc
chloride was heated at 80°C for 4 h. Extraction with
isooctane provided 0.87 g of a mixture of methyl 4-(di-
ethoxymethyl)benzenecarboxylate 4d and ethyl 4-(di-
ethoxymethyl)benzenecarboxylate 4e in a ratio of 1.7 : 1.0.
Attempts to isolate compounds in pure state failed.
3
3
OCH2Me, JHH = 7.0 Hz), 3.49 q (8H, OCH2, JHH
7.0 Hz), 5.44 s (2Н, СНO2), 7.37 s (4Н, С6Н4).
=
1H NMR spectra were registered on an AVANCE
400WB (400.13) spectrometer in CDCl3, internal
reference TMS.
ACKNOWLEDGMENTS
This work was financially supported by the Ministry
of Education and Science of Russia in the frame of the
basic part of the governmental contract (no. 1629).
Reaction of 3-(dibromomethyl)phenylacetate (1c)
with trimethyl orthoformate (2). A mixture of 2.48 g
(0.008 mol) of compound 1c, 3.40 g (0.032 mol) of
trimethyl orthoformate 2, and 0.1 g (0.0008 mol) of
zinc chloride was heated at 50°C for 1 h. Due to the
presence of a weak signal of aldehyde proton (10.03 ppm)
in the 1H NMR spectrum of the reaction mixture, 2.55 g
(0.024 mol) of compound 2 was added and heating was
continued for 2 h. After the excess orthoester was
removed in a vacuum, the residue was treated with
isooctane to obtain 0.5 g (30%) of 3-(dimethoxy-
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Khimiya atsetalei (Chemistry of Acetals), Moscow:
Nauka, 1975.
3. Monral, E. and Hand, C.R., J. Am. Chem. Soc., 1950,
1
methyl)phenyl acetate 4e as colorless oil. Н NMR
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spectrum (CDCl3), δ, ppm: 2.35 s (3Н, COMe), 3.38 s
(6Н, ОMe), 5.51 s (1Н, СНO2), 7.12–7.46 m (4Н,
С6Н4). 13С NMR spectrum (CDCl3), δС, ppm: 20.9
(COMe), 52.0 (OMe), 101.6 (CHO2), 120.2, 121.5,
124.1, 127.1, 127.5, 129.9, 139.8 (С6H4), 168.7 (CO).
Found, %: С 62.63; Н 6.59. С11H14O4. Calculated, %:
С 62.86; Н 6.67.
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RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 9 2016