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J Chem Crystallogr (2015) 45:419–426
clomazone and topramezone have been developed as her-
bicides, and isoxadifen-ethyl used as a herbicide safeners
[5]. And there are other more isoxazole herbicides [6–9].
Furthermore, the excellent photoelectric properties and
carrier transmission capacity of isoxazole compounds add
to their wide use in photoelectric functional materials and
organic photoconductors [10].
flask, added 1 g anhydrous aluminum chloride, a solution
of 21.6 g (0.136 mol) bromine in 125 mL 1,2-dichlor-
oethane was added into the flask in 30 min, heated to
60 °C for 4 h, cooled to room temperature, washed by
10 % hydrochloric acid, saturated NaHCO3 solution and
water, dried, distilled off 1,2-dichloroethane under reduced
pressure. Brown liquid 29.17 g (decompose, b.p.
1
In this paper, a novel pesticide intermediates 3-(6-
bromo-2-methyl-3-(methylsulfonyl)phenyl)-4,5-dihy-
droisoxazole was synthesized and the structure of these
266.717 °C [12]). Yield 95.9 %. MS (M?H?): 231.0. H
NMR (400 MHz, CDCl3) d 7.39 (d, J = 8.5 Hz, 1H, Ar–
H), 6.92 (d, J = 8.5 Hz, 1H, Ar–H), 2.44 (s, 3H, SO2–
CH3), 2.42 (s, 3H, Ar–CH3), 2.38 (s, 3H, Ar–CH3).
1
compounds were characterized by mass spectra (MS), H
NMR, infrared (IR) and single crystal X-ray diffraction.
Synthesis of 2,3-Dimethyl-4-methylsulfonyl-1-
bromobenzene (3)
Experiments
15 g (65 mmol) 2,3-dimethyl-4-methylsulfonyl-1-bro-
mobenzene and 150 mL acetic acid was added into three-
necked flask, heated to 100 °C, added 150 mL 30 % hydro-
gen peroxide then placed at 100 °C for 2 h (the color of the
solution changed from orange to colorless), cooled to room
temperature, reaction mixture was added into 1200 mL water,
placed overnight, filtered, dried. White powder 13.70 g. Yield
80.2 %. MS (M?H?): 262.9. IR m 3087 (Ar–CH3), 3006 (Ar–
H), 2924 (SO2–CH3), 1300, 1124 (–SO2–); 1H NMR
(400 MHz, CDCl3) d 7.79 (d, J = 8.6 Hz, 1H, Ar–H), 7.61
(d, J = 8.5 Hz, 1H, Ar–H), 3.09 (s, 3H, SO2–CH3), 2.71 (s,
3H, Ar–CH3), 2.48 (s, 3H, Ar–CH3).
Instruments and Reagents
MS were determined with an Agilent 1100LC-MS mass
spectrometer. IR spectra of synthetic compounds within
400–4000 cm-1 were recorded with a Nicolet 170 SXFT-
IR spectrometer (mixed with KBr and pressed into pellets).
1H NMR spectra in CDCl3 or (CD3)2SO solvent were
recorded with an INOVA-400 spectrometer in the presence
of tetramethylsilane as an internal standard. Intensity data
were collected on Bruker Apex II CCD detector.
All chemicals and solvents are of commercial reagent
grade and used without further purification except the
bromine. While the single crystal specimens of 6 and 8
were acquired via slow evaporation of their methanol
solutions at room temperature.
Synthesis of 3-Bromomethyl-2-methyl-4-methylsulfonyl-1-
bromobenzene (4) and 2-Bromo methyl-3-ethyl-4-
methylsulfonyl-1-bromobenzene (5)
Synthesis Section
4 g (15.3 mmol) 2,3-dimethyl-4-methylsulfonyl-1-bro-
mobenzene, 0.16 g azobisisobutyronitrile and 10 mL car-
bon tetrachloride was added in three-necked flask, heated
to 80 °C, added 2.72 g NBS (15.3 mmol), reflow 4 h under
lamp, suction filtered when it was hot, the filtrate was
distilled under reduced pressure. The solid was separated
by column chromatography (eluent was petroleum ether:-
ethyl acetate = 5:1, V/V).
Synthesis of 1,2-Dimethyl-3-methylsulfanyl-benzene (1)
75 g (0.62 mol) 2,3-dimethylaniline and 70 g (1.09 mol)
copper and 500 mL dimethyl disulfide was added into
three-necked flask, heated to 55 °C, added a solution of
100 g (0.97 mol) tertbutyl nitrite into the flask in 30 min at
55 °C, heated to 60 °C for 2 h, cooled to room tempera-
ture, filtered, the filtrate was washed by 10 % hydrochloric
acid, saturated NaHCO3 solution and water, dried, distilled
under reduced pressure, and collected the component of
128–130 °C at 4 kPa (m.p. 16 °C, b.p. 213.369 °C [11]).
Orange liquid 78.13 g. Yield 82.9 %.
3-Bromomethyl-2-methyl-4-methylsulfonyl-1-bromobenzene
(4) White powder 2.94 g (m.p. 99.3–100.1 °C), yield
56.5 %. MS (M?H?): 341.1; IR m 3084 (Ar–CH3), 3012
1
(Ar–H), 2920 (SO2–CH3), 1303–1126 (–SO2–); H NMR
(400 MHz, CDCl3) d 7.85 (d, J = 8.6 Hz, 1H, Ar–H), 7.75
(d, J = 8.6 Hz, 1H, Ar–H), 4.91 (s, 2H, –CH2Br), 3.28 (s,
3H, SO2–CH3), 2.62 (s, 3H, Ar–CH3).
Synthesis of 2,3-Dimethyl-4-methylsulfanyl-bromobenzene
(2)
2-Bromomethyl-3-methyl-4-methylsulfonyl-1-bromoben-
zene (5) White powder 1.77 g (m.p. 157.6–158.1 °C),
yield 34.5 %. MS (M?H?): 341.1; IR m 3081 (Ar–CH3),
20 g (0.13 mol) 1,2-dimethyl-3-methylsulfanylbenzene and
125 mL 1,2-dichloroethane was added into three-necked
123