4
ꢀ(Dibromomethyl)benzenecarbaldehyde
Russ.Chem.Bull., Int.Ed., Vol. 65, No. 1, January, 2016
193
Thus, the reaction of trimethyl phosphate with 1,4ꢀbisꢀ
dibromomethyl)benzene allowed us to obtain 4ꢀ(diꢀ
(1.8 mmol) of 4ꢀ(dibromomethyl)benzenecarbaldehyde (7),
.11 g (0.0018 mmol) of isopropylamine (12а) and 0.2 g of moꢀ
0
(
lecular sieves 3 Å in 10 mL of dry benzene was thermostated at
room temperature for 24 h. NꢀIsopropylꢀ4ꢀ(dibromomethyl)ꢀ
benzenecarbimine (14а) (0.44 g, 77%) in the form of yellow oil
was obtained by filtration through the molecular sieves followed
by the removal of the solvent in vacuo provided by waterꢀjet
bromomethyl)benzenecarbaldehyde, which was then transꢀ
formed into acetals and imines, included those containing
an acetal group.
The content and structure of the substances syntheꢀ
1
13
sized were confirmed by the element analysis, Н and
С
1
3
pump. Н NMR (СDCl ), δ: 1.25 (d, 6 Н, СНMe , J
= 6.3 Hz);
3
2
Н,Н
NMR spectroscopy and mass spectroscopy.
3.54 (sept, 1 Н, СНMe , 3J
= 6.3 Hz); 6.61 (s, 1 Н, CHBr );
2
Н,Н
2
3
7
.55, 7.72 (both d, 2 Н, С Н , J
= 8.5 Hz); 8.25 (s, 1 Н,
Н,Н
6
4
13
СН=N). С NMR (CDCl ), δ ,: 24.17 (Ме); 40.45 (СНBr );
3
С
2
Experimental
6
1
1.80 (NCH); 126.81, 128.29 (СНarom); 126.81, 130.05, 137.86,
43.63 (С ); 157.0 (CH=N). MS (EI, 70 eV), m/z (I (%)):
arom
rel
1Н and 13С NMR spectra were recorded on Tesla BSꢀ567A
+
+
i
+
317 [М] (1.0), 302 [М – Ме] (16.2), 276 [М – Pr + 2 Н]
(0.32), 238 [М – Br] (100.0), 223 [М – Br – Ме] (38.5), 182
[С Н Br] (1.4), 168 [С Н Br] (9.4), 144 [М – 2 Br – Ме]
(24.7), 117 [M – 2 Br – Pr + H] (22.6), 103 [M – CHBr – Pr ]
2
+
+
(
(
working frequencies of 100 MHz) and Bruker Avance 400WB
working frequencies of 400.13 and 100.61 MHz) instruments in
+
+
+
8
7
7
i
5
+
i +
CDCl . The chemical shifts are shown in respect to SiMe using
3
4
+
+
the signals of residual protons and carbon nuclei of deuterated
solvent.
(11.1), 89 [С Н ] (61.9), 43 [C H ] (55.3). Found (%): С, 41.16;
7 5 3 7
Н, 4.03; Br, 49.95. C H Br N. Calculated (%): С, 41.41; Н, 4.11;
11
13
2
Chromatoꢀmass spectrometry was performed on DFS deꢀ
vice (Thermo Electron Corporation, Germany). Electron imꢀ
pact was used as an ionization method. Energy of the ionized
electrons was 70 eV, the ion source temperature was 250 °C.
A 50 m capillary column BPX5 (SGE company) with a diameter
of 0.32 mm was used. The carrier gas was helium. For comꢀ
pound 14с the system of the direct introduction of a substances
in the ion source was applied. The temperature of the evaporator
ampoule varied from 50 to 350 °C. The obtained data were proꢀ
cessed using Xcalibur programme. Before the introduction into
the device the probe of the studied sample was dissolved in pure
grade chloroform in the weight ratio of ∼ 1 : 20.
Br, 50.09.
Nꢀ(4ꢀMethoxyphenyl)ꢀ4ꢀ(dibromomethyl)benzenecarbimine
(14b). Compound 14b (0.35 g, 100%) of in form of yellow crysꢀ
tals, m.p. 120—122 °C was obtained from the reaction mixture
containing 0.25 g (0.9 mmol) of 4ꢀ(dibromomethyl)benzeneꢀ
carbaldehyde (7), 0.11 g of (0.9 mmol) 4ꢀmethoxybenzeneamꢀ
ine (12b) and 0.1 g of molecular sieves 3 Å in 6 mL of dry
1
benzene. Н NMR (СDCl ), δ: 3.82 (s, 3 Н, ОMe); 6.64 (s, 1 Н,
3
3
CHBr ); 6.87, 7.18 (both d, 2 Н, С Н ОMe, J
= 9.1 Hz);
2
6
3
4
Н,Н
7.63, 7.88 (both d, 2 Н, С Н СHBr , J
СН=N). Found (%): С, 46.79; Н, 3.29; N, 3.51. C H Br NO.
Calculated (%): С, 47.02; Н, 3.43; N, 3.65.
= 7.8 Hz); 8.44 (s, 1 Н,
6
4
2
Н,Н
15
13
2
The peaks of the ions containing the most wideꢀspread isoꢀ
topes, in particular Br isotope, were indicated.
Nꢀ(2,2ꢀDiethoxyethyl)ꢀ4ꢀ(dibromomethyl)benzenecarboimine
(14c). Compound 14c (0.65 g, 93%) in form of yellow crystals,
m.p. 34—35 °C was obtained from the reaction mixture containꢀ
ing 0.5 g (1.8 mmol) of 4ꢀ(dibromomethyl)benzenecarbaldehyde
(7), 0.24 g (1.8 mmol) of 2,2ꢀdiethoxyethanamine (12c) and
7
9
Reaction between trimethyl phosphate (1а) and 1,4ꢀbis(diꢀ
bromomethyl)benzene (6). А. The ratio of 1.5 : 1.0. The reaction
mixture containing 4.2 g (30 mmol) of trimethyl phosphate (1а)
and 8.44 g (20 mmol) of 1,4ꢀbis(dibromomethyl)benzene (6)
was heated in an oil bath at 180 °C for 5.5 h. The obtained
products (7 and 8) were separated by extraction with isooctane.
By means of colomn chromatography (benzene as an eluent)
1
0.2 g of molecular sieves 3 Å in 8 mL of dry benzene. Н NMR
3
(СDCl ), δ: 1.15 (t, 6 Н, OCH Me, J
= 7.0 Hz); 3.33—3.81
3
2
Н,Н
3
(m, 6 Н, NCH , 2 ОСН Me); 4.77 (t, 1 Н, СНО , J = 5.2 Hz);
6.63 (s, 1 Н, CHBr ); 7.59, 7.72 (both d, 2 Н, С Н , J = 8.4 Hz);
Н,Н
8.26 (s, 1 Н, СН=N). С NMR (CDCl ), δ : 15.45 (OCH Me);
3 С 2
2
2
2
Н,Н
3
2
6
4
13
2
.34 g (42%) of 4ꢀ(dibromomethyl)benzenecarbaldehyde (7)
were isolated. The substance represented colorless crystals,
40.08 (СНBr ); 62.45 (NCH ); 64.60 (OCH Me); 101.89 (CHO );
2 2 2 2
1
m.p. 89—90 °C. Н NMR (CDCl ), δ: 6.63 (s, 1 H, СНВr );
126.80, 128.39 (СНarom); 137.48, 143.91 (Сarom); 161.70 (CH=N).
3
2
13
MS (EI, 70 eV), m/z (I (%)): 346 [M – EtO]+ (0.73), 318
7
.67—7.93 (m, 4 Н, С Н ); 10.02 (s, 1 Н, СНО). С NMR
6 4
rel
+
+
(
СDCl ), δ ,: 39.49 (СНBr ); 127.35, 130.06 (СНarom); 137.04,
[M – EtO – Et + H] (0.29), 302 [M – (EtO) + H] (0.07),
2
288 [M – CH(OEt) ] (0.43), 268 [M – EtO – Br + H] (2.4),
2
261 [C H Br ] (0.4), 238 [M – EtO – Et – Br] (1.0), 209
8 7 2
[M – CH(OEt) – Br] (2.2), 197 [M – CH(OEt) – CHBr + H]
2 2
(1.8), 182 [C H Br] (4.7), 130 [C H O N] (6.1), 103
8 7 6 12 2
[C H O ] (100.0), 75 [C H O ] (63.8). Found (%): С, 42.53;
5 11 2 3 7 2
3
C
2
+
+
1
2
–
47.39 (Сarom); 191.11 (CHO). MS (EI, 70 eV), m/z (I (%)):
rel
+
+
+
+
47 [М – CHO] (0.13), 197 [М – Br] (91.3), 168 [М – CHO
+
+
+
+
+
+
Br] (7.8), 89 [С Н ] (100.0), 63 [C Н ] (77.5), 50 [C Н ]
7
5
5
3
4
2
+
+
(
20.4). Found (%): С, 34.36; Н, 2.12; Br, 57.41. C H Br O.
8
6
2
+
+
Calculated (%): С, 34.57; Н, 2.18; Br, 57.50. By means of chroꢀ
matography 1,4ꢀbenzenedicarboxaldehyde (8) (0.64 g, 24%) was
isolated. It represented colorless crystals, m.p. 115—116 °C.
Н, 4.79; Br, 40.51; N, 3.44. C H Br NO . Calculated (%):
14
19
2
2
С, 42.77; Н, 4.88; Br, 40.65; N, 3.56.
1
Н NMR (СDCl ), δ: 8.04 (s, 4 Н, С Н ); 10.12 (s, 2 Н, СНО).
Nꢀ(4,4ꢀDiethoxybutyl)ꢀ4ꢀ(dibromomethyl)benzenecarbimine
(14d). Compound 14d (0.72 g, 92%) in the form of yellow oil was
obtained from the reaction mixture containing 0.5 g (1.8 mmol)
of 4ꢀ(dibromomethyl)benzenecarbaldehyde (7), 0.32 g (1.8 mmol)
of 4,4ꢀdiethoxybuthanamine (12d) and 0.2 g of molecular sieves
3
6
4
B. The ratio of 2.1 : 1.0. The reaction mixture containing
.94 g (21 mmol) of trimethyl phosphate (1а) and 4.22 g
2
(
10 mmol) of 1,4ꢀbis(dibromomethyl)benzene (6) was heated in
an oil bath at 180 °C for 21 h. Compound 8 (0.96 g, 72%) was
separated by extraction with isooctane. It represented colorless
crystals, m.p. 115—116 °C (Ref. 2: m.p. 115—116 °C).
1
3 Å in 10 mL of dry benzene. Н NMR (СDCl ), δ: 1.21 (t, 6 Н,
3
3
OCH Me, JН,Н = 7.0 Hz); 1.43—1.80 (m, 4 Н, СН СН );
2
2
2
Reaction between 4ꢀ(dibromomethyl)benzenecarbaldehyde (7)
and isopropylamine (12а). The reaction mixture containing 0.5 g
3.20—3.70 (m, 6 Н, ОСН , NCH ); 4.43 (t, 1 Н, CHO ,
2 2 2
3
JН,Н = 5.0 Hz); 6.59 (s, 1 Н, CHBr ); 7.52, 7.68 (both d, 2 Н,
2