J.-H. Kwak et al. / Tetrahedron 67 (2011) 9401e9404
9403
4. Experimental section
4.1. General information
(213 mg, 1.00 mmol), Pd(OAc)2 (22.5 mg, 0.100 mmol, 10 mol %),
RuPhos
(2-dicyclohexylphosphino-20,60-diisopropoxy-biphenyl,
94.0 mg, 0.20 mmol, 20 mol %), and K2CO3 (420 mg, 3.00 mmol).
The vessel was sealed with a septum, and DME/H2O (v/v¼5:1,
20 mL) was added via syringe. The reaction was heated by micro-
wave (BiotageÒ Initiator, EXP EU 355301, 115 W) at 130 ꢀC for
10 min. After the aryl bromide was totally consumed (the reaction
was monitored by TLC), the reaction mixture was cooled to rt. The
residual compound was dissolved in ethyl acetate (100 mL), and the
insoluble salts were filtered through a thin pad of silica gel. The
combined organic layers were washed with H2O, and brine, dried
over MgSO4, and concentrated in vacuo. Purification via flash col-
umn chromatography (EtOAc/hexanes¼1:10) of the residue affor-
ded 202 mg (72%) of 1 as a colorless oil; 1H NMR (400 MHz, CDCl3)
Unless noted otherwise, all starting materials and reagents were
obtained from commercial suppliers and were used without further
purification. Air and moisture sensitive reactions were performed
under an argon atmosphere. Flash column chromatography was
performed using silica gel 60 (230e400 mesh, Merck) with the
indicated solvents. Thin-layer chromatography was performed us-
ing 0.25 mm silica gel plates (Merck). Melting points were mea-
sured on an Electrothermal IA 9100 melting point apparatus and
are uncorrected. Infrared spectra were recorded on a Jasco FT-IR
4100 spectrometer. Low and high-resolution fast atom bombard-
ment (FAB) mass spectra were obtained with JEOL JMS-700 in-
strument. 1H and 13C NMR spectra were recorded on either a Bruker
AVANCE III 400 MHz or Bruker AVANCE 500 MHz Spectrometer as
solutions in deuteriochloroform (CDCl3) or deuterioacetone
(CD3COCD3). 1H NMR data were reported in the order of chemical
shift, multiplicity (s, singlet; d, doublet; t, triplet; m, multiplet and/
or multiple resonances), number of protons, and coupling constant
in hertz (Hz).
d
7.30 (d, J¼8.4 Hz, 1H), 7.25 (m, 1H), 7.05 (m, 2H), 6.97 (d, J¼8.4 Hz,
1H), 6.92 (d, J¼8.4 Hz, 1H), 6.08e5.93 (m, 2H), 5.13e5.05 (m, 5H),
3.89 (s, 3H), 3.44 (d, J¼6.8 Hz, 2H), 3.36 (d, J¼6.6 Hz, 2H); 13C NMR
(100 MHz, CDCl3)
d 157.2, 151.0, 138.0, 136.7, 132.4, 130.7, 130.4,
130.0, 129.2, 129.0, 128.1, 128.0, 116.1, 115.8, 115.7, 111.1, 55.7, 39.6,
34.5; LRMS (FAB) m/z 281 (MþHþ).
Acknowledgements
4.2. Experimental procedure
This research was supported by the Medical Research Center
program (2010-0029480), the Regional Core Research Program
(Chungbuk BIT Research-Oriented University Consortium) through
the National Research Foundation of Korea, and by the Ministry of
Land, Transport and Maritime Affairs, Republic of Korea.
4.2.1. 2-Allyl-4-bromo-1-methoxybenzene (7). A mixture of anhy-
drous K2CO3 (4.2 g, 30 mmol), 2-allyl-4-bromophenol (3.2 g,
15 mmol), and acetone (30 mL) was stirred for 30 min then iodo-
methane (2.7 g, 19 mmol) was added at room temperature. After
4 h, solvent was evaporated then water (15 mL) was added. The
mixture was extracted with ether (3ꢂ20 mL). The combined ex-
tracts were washed with water (10 mL), dried over anhydrous
MgSO4 and the solvent was evaporated. Purification on silica gel
(hexane only) provided 2-allyl-4-bromo-1-methoxybenzene (7)
(3.7 g, 94%) as a pale yellow oil; IR (thin film) 3081,1638, 1488, 1242,
Supplementary data
Supplementary data associated with this article can be found in
clude MOL files and InChiKeys of the most important compounds
described in this article.
1032, 803, 654 cmꢁ1 1H NMR (500 MHz, CDCl3)
; d 7.29 (dd, 1H,
J¼8.6, 2.5 Hz), 7.24 (ds,1H, J¼2.5 Hz), 6.72 (d,1H, J¼8.6 Hz), 5.94 (m,
1H), 5.06 (m, 2H), 3.80 (s, 3H), 3.34 (d, 2H, J¼6.6 Hz); 13C NMR
(100 MHz, CDCl3)
112.0, 55.6, 33.9.
d. 156.4, 136.0, 132.4, 131.0, 129.8, 116.1, 112.7,
References and notes
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C10H11BF3OK (Mþ): 254.0492; found 254.0482.
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