C. Cao, L. Wang, Z. Cai, L. Zhang, J. Guo, G. Pang, Y. Shi
FULL PAPER
lic reaction partner. The coupling of sterically demanding
chlorides or bromides produced more dehalogenated by-
Acknowledgments
product. It is probably because sterically demanding sub- We gratefully acknowledge Xuzhou Normal University
(KY2008103, KY2008104, and 09XLY02), Qing Lan Project of
Jiangsu Education Committee (08QLT001 and 08QLD006), State
Key Laboratory of Inorganic Synthesis and Preparative Chemistry
at Jilin University (2009-06), Scientific Research Foundation (SRF)
for the Returned Overseas Chinese Scholars (ROCS), State Educa-
tion Ministry (SEM), and National Natural Science Foundation of
China (NSFC) (21071121) for financial support of this work.
strates should lead to a decrease in the rate of transmet-
alation, favoring the dehalogenation pathway. However, the
mechanism is still unclear. We have evidence to suggest that
the ketone serves as a hydrogen source. When naphthyl bro-
mide was treated with 3-pentanone, 10% naphthalene was
observed; however, no naphthalene was detected without
ketones. Further mechanistic study is still underway.
Conclusions
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In summary, we were able to successfully carry out the
α-arylation of a series of aryl and alkyl ketones with com-
plex 3 in dry THF in the presence of sodium tert-butoxide
by using a variety of aryl halides (activated, unactivated,
and sterically hindered aryl halides) under mild reaction
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Experimental Section
General Procedure for Monoarylation: In a glove box, (SIPr)Pd(Py)-
Cl2 (3; 0.005 mmol, 3.2 mg) and sodium tert-butoxide (0.5 mmol,
48 mg) were added to a vial equipped with a magnetic bar and
sealed with a screw cap fitted with a septum. The ketone
(0.5 mmol), the aryl halide (0.5 mmol), and anhydrous THF (1 mL)
were injected through the septum. If one of the two starting materi-
als was a solid, it was added to the vial inside the glove box. The
reaction mixture was then stirred at the indicated temperature for
the indicated amount of time and was monitored by GC–MS and
TLC. When the reaction reached completion, the mixture was di-
luted with diethyl ether and filtered through a pad of Celite with
washing, and the solvent was evaporated in vacuo. Whenever neces-
sary, the product was purified by recrystallization or flash column
chromatography on silica gel.
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General Procedure for Diarylation: The procedure is same as above.
(SIPr)Pd(Py)Cl2 (3; 0.010 mmol, 6.4 mg) and sodium tert-butoxide
(1 mmol, 96 mg), ketone (0.5 mmol), aryl halide (1 mmol), and
THF (1 mL).
Supporting Information (see footnote on the first page of this arti-
cle): Experimental procedures, product isolation, and analytical
and spectroscopic data.
Received: October 20, 2010
Published Online: January 31, 2011
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