Categories: C-F Bond Formation >
Synthesis of allyl fluorides
Recent Literature
The solid, air-stable peptide coupling reagent TFFH (tetramethylfluoroformamidinium
hexafluorophosphate) activates various alcohols towards deoxofluorination under
mild conditions, that are even compatible with carbonyl functional groups.
G. Bellavance, P. Dubé, B. Nguyen, Synlett, 2012, 23,
569-572.
A rapid allylic fluorination method of trichloroacetimidates with Et3N·3HF
as reagent in conjunction with an iridium catalyst can be conducted at room
temperature under ambient air and provides branched allylic fluorides with
complete regioselectivity in high yields. The reaction shows considerable
functional group tolerance. The use of [18F]KF·Kryptofix allowed
18F- incorporation in 10 min.
J. J. Topczewski, T. J. Tewson, H. M. Nguyen, J. Am. Chem. Soc., 2011,
133, 19318-19321.
A transition-metal-free chemo-, regio-, and stereoselective electrophilic
fluorodesilylation of α-silyl-substituted allylboronate esters with Selectfluor
provides a variety of (E)-boryl-substituted allyl fluorides in good
yields. Further modifications of the obtained (E)-boryl-substituted allyl
fluorides afford allyl or alkyl fluoride derivatives.
Y. Jung, S. H. Cho, Synlett, 2023,
34,
2165-2168.
A silver-catalyzed vinylogous fluorination of vinyl diazoacetates generates
γ-fluoro-α,β-unsaturated carbonyls. Fluorination of farnesol and steroid
derivatives was achieved.
C. Qin, H. M. L. Davies, Org. Lett., 2013,
15, 6152-6154.
In an enantioselective fluorination of allylic alcohols under chiral anion
phase-transfer conditions, an in situ generation of a directing group proved
crucial for achieving effective enantiocontrol. In the presence of such a
directing group, a range of acyclic substrates underwent fluorination to afford
highly enantioenriched α-fluoro homoallylic alcohols.
W. Zi, Y.-M. Wang, F. D. Toste, J. Am. Chem. Soc., 2014,
136, 12864-12867.
An organocatalytic system of L-proline and salicylic acid enables a highly
stereoselective synthesis of α,α-difluoro-γ,γ-disubstituted butenals. The
reaction offers a wide substrate scope and excellent E stereoselectivity
in most cases.
S. Arimitsu, M. Nakasone, J. Org. Chem.,
2016, 81, 6707-6713.
A dianionic
phase-transfer catalyst enables an asymmetric fluorofunctionalization of γ,γ-disubstituted allylamine
derivatives. Depending on the substituents on the alkene moiety, the
reaction afforded chiral allylic fluorides and fluorinated dihydrooxazines in a
highly enantioselective manner.
T. Niwa, K. Nishibashi, H. Sato, K. Ujiie, K. Yamashita, H. Egami, Y.
Hamashima, J. Am. Chem. Soc.,
2021, 143, 16599-16609.
Related
A Pd-catalyzed gem-difluoroallylation of organoborons using
3-bromo-3,3-difluoropropene (BDFP) proceeds in high efficiency with high α/γ-substitution
regioselectivity. The reaction offers low catalyst loading (0.8 to 0.01 mol %),
broad substrate scope, and excellent functional group compatibility, thus
providing a facile route for practical application in drug discovery and
development.
Q.-Q. Min, Z. Yin, Z. Feng, W.-H. Guo, X. Zhang, J. Am. Chem. Soc., 2014,
136, 1230-1233.