In conclusion, a convenient and highly effective Ir-catalyzed
a-alkylation of ketones with subsequent reduction and deprotec-
tion/cyclization methodology for the synthesis of valuable 2,5-
disubstituted tetrahydrofurans was developed. Notably, com-
mercially available substituted acetophenones as well as solketal
a readily available derivative of the bulk chemical glycerol are
used in the atom-economic transfer hydrogen reaction, whereby
water is the only by-product. The subsequent reduction and de-
protection/cyclization proceed under mild reaction conditions
and afford 2,5-disubstituted tetrahydrofurans in good to high
overall yields. In addition, a more practical, one-pot three-step
procedure has been developed.
8 Y. M. A. Yamada and Y. Uozumi, Org. Lett., 2006, 8, 1375–1378.
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10 For the alkylation of methyl ketones with primary alcohols promoted
by Nickel nanoparticles (1 equiv), see: F. Alonso, P. Riente and M.
Yus, Synlett, 2007, 1877–1880.
11 (a) K. Taguchi, H. Nakagawa, T. Hirabayashi, S. Sakaguchi and
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Acknowledgements
13 Iridium catalyzed alkylation of acetates: Y. Iuchi, Y. Obora and Y.
Ishii, J. Am. Chem. Soc., 2010, 132, 2536–2537.
V.B.P. thanks the Alexander von Humboldt foundation for a
post-doctoral research fellowship.
14 For the Ir catalyzed alkylation of other substrates with alcohols (C–C
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