Nuria Garcꢀa et al.
COMMUNICATIONS
tillation and stored under N2. Solvents were dried by stan-
dard methods. For the preparation of non-commercially
available sulfoxides see the Supporting Information. H and
aromatic amine 4 was obtained in pure form without further
purification, unless otherwise stated, in the yields reported
in Table 3. Characterization data and NMR spectra are pre-
sented in the Supporting Information.
1
13C NMR spectra were recorded on a Varian Mercury-Plus
300 or Varian Inova 400 spectrometers, using CDCl3,
DMSO-d6, or acetone-d6 as solvents and internal standards.
GC-MS and low resolution mass spectra (LR-MS) were re-
corded on an Agilent 6890N/5973 Network GC System,
equipped with an HP-5MS column. High resolution mass
spectra (HR-MS) were recorded on a Micromass AutoSpect
spectrometer using EI at 70 eV. Products that had been re-
ported previously were isolated in greater than 95% purity,
as determined by 1H NMR spectroscopy and capillary gas
chromatography (GC). The microwave heating was per-
formed in a microwave reactor (CEM Discover S-Class)
with a single-mode microwave cavity producing continuous
irradiation (temperature measurements were conducted
using an IR sensor located below the microwave cavity
floor, and reaction times refer to the total hold time at the
indicated temperature. The maximum wattage supplied was
300 W).
Acknowledgements
We are grateful to the Ministerio de Ciencia e Innovaciꢀn
(MICINN) and FEDER (CTQ2010-15358 and CTQ2009-
09949/BQU) and Junta de Castilla y Leꢀn (BU021A09 and
GR-172) for financial support. P.G.-G. and M.A.F.-R. thank
MICINN for “Juan de la Cierva” and “Ramꢀn y Cajal” con-
tracts.
References
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VCH, Weinheim, 2008.
MoO2Cl2ACHTUNGTRENNUNG(DMF)2
The catalyst was prepared in almost quantitative yield from
commercially available Na2MoO4·2H2O as previously de-
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General Procedure for Deoxygenation of Sulfoxides 1
with Pinacol Catalyzed by MoO2Cl2ACTHNUTRGENUG(N DMF)2
A mixture of the corresponding sulfoxide 1 (2 mmol), pina-
col (472 mg, 4 mmol), and MoO2Cl2A(DMF)2 (14 mg,
CTHUNGTRENNUNG
0.04 mmol) was stirred at 908C until the sulfoxide was con-
sumed (method A), as determined by GC-MS or TLC, or ir-
radiated in a 10-mL sealed tube in the microwave cavity at
1208C for 5–10 min (method B). The reaction mixture was
cooled to room temperature and the crude mixture was
treated with 0.5M NaOH (25 mL) and extracted with Et2O
(3ꢄ20 mL). The combined organic layers were washed with
brine and dried over anhydrous Na2SO4, and the solvents
were evaporated under reduced pressure. The corresponding
sulfide 2 was obtained in pure form without further purifica-
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and NMR spectra are presented in the Supporting Informa-
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General Procedure for the Reduction of Nitro
Compounds 3 with Pinacol Catalyzed by
MoO2Cl2ACHTUNGTRENNUNG(DMF)2
A mixture of the corresponding nitroaromatic derivative 3
(1 mmol), pinacol (472 mg, 4 mmol), and MoO2Cl2A(DMF)2
CTHUNGTRENNUNG
(17 mg, 0.05 mmol) in dry o-xylene (2 mL) or toluene
(2 mL) was stirred at 1308C (method A) or irradiated in a
10-mL sealed tube in the microwave cavity at 1508C
(method B) until the reduction was completed, as deter-
mined by GC-MS or TLC. The reaction mixture was cooled
to room tempertaure and the crude mixture was treated
with 0.5M NaOH (25 mL) and extracted with Et2O (3ꢄ
20 mL). The combined organic layers were washed with
brine and dried over anhydrous Na2SO4, and the solvents
were evaporated under reduced pressure. The corresponding
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326
ꢃ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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