Categories: C-C Bond Formation > Chains >
Allylic Substitutions, Allylation
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Name Reactions
Recent Literature
Efficient enantioselective Cu-catalyzed alkylations of aromatic and
aliphatic allylic phosphates bearing di- and trisubstituted olefins are
promoted in the presence of a readily available chiral amino acid-based
ligand. Tertiary and quaternary stereogenic carbon centers are delivered
regioselectively in high ee.
M. A. Kacprzynski, A. H. Hoveyda, J. Am. Chem. Soc.,
2004,
126, 10676-10681.
A promising new approach to a generalized allylation process uses various
easily accessible allyl diphenylphosphine oxides as radical trapping agents
for the allylation of ditihocarbonates.
G. Ouvry, B. Quiclet-Sire, S. Z. Zard, Angew. Chem. Int. Ed., 2006,
45, 5002-5006.
The palladium-catalyzed reaction of allyl acetates with aryl- and
vinyltin reagents gave good yields of cross-coupled products. The reaction
was mild and tolerant of functionality (-CO2R, -OH, -OSiR3,
-OMe) in the tin reagent. Inversion of stereochemistry at the acetate center
was observed, with retention of the geometry of the olefin of the allyl
group and with exclusive coupling at the primary position. Retention of
geometry of the olefin in the vinyltin reagents was also observed.
L. Del Valle, J. K. Stille, L. S. Hegedus, J. Org. Chem, 1990,
55, 3019-3023.
Enantioselective copper-catalyzed allylic alkylations of Grignard reagents were
performed on allylic bromides with a protected hydroxyl or amine functional
group using Taniaphos as a ligand. The terminal olefin moiety in the products
can be transformed into various functional groups without racemization.
A. W. van Zijl, F. López, A. J. Minnaard, B. L. Feringa, J. Org. Chem., 2007,
72, 2558-2563.
A chemo- and regioselective, Cu-catalyzed asymmetric addition of Grignard
reagents to 3-bromopropenyl esters provides allylic esters in high yields
and enantioselectivities using Taniaphos as ligand. The method is a
practical route to chiral, nonracemic allylic alcohols.
K. Geurts, S. P. Fletcher, B. L. Feringa, J. Am. Chem. Soc., 2006,
128, 15572-15573.
Chelated amino acid ester enolates are excellent nucleophiles for allylic
alkylations. With these enolates, even terminal π-allyl palladium complexes react
without significant isomerization.
K. Krämer, U. Kazmaier, J. Org. Chem., 2006,
71, 8950-8953.
Efficient Addition of Allylsilanes to α,β-Enones Using Catalytic Indium and
Trimethylsilyl Chloride
P. H. Lee, D. Seomoon, S. Kim, K. Nagaiah, S. V. Damle, K. Lee, Synthesis,
2003, 2023-2026.
The reaction of alkoxides with boron trichloride results in the generation
of cations that can be allylated in subsequent transformations. The absence
of Brřnsted acids can make a significant difference in such syntheses.
G. W. Kabalka, M.-L. Yao, S. Borella, J. Am. Chem. Soc., 2006,
128, 11320-11321.
G. W. Kabalka, M.-L. Yao, S. Borella, J. Am. Chem. Soc., 2006,
128, 11320-11321.
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Enantioselective Allylic Carbon-Carbon Bond Construction |
