Nucleoside analogues bearing a fluorine in the C2'-position have been synthesized by S2-like cyclizations of acyclic thioaminal precursors. This strategy provides access to two scaffolds, d-1',2'-cis-thiofuranosides and d-1',2'-trans-furanosides, which are difficult to generate using the standard approach for nucleoside synthesis. The addition of silylated nucleobases onto model C2-fluorinated dithioacetal substrates resulted in 1,2-syn diastereoselectivity, which is consistent with the C2-F and S-alkyl moiety being in close proximity. A new series of analogues bearing a C3' all-carbon quaternary center along with a C2'-F atom have also been synthesized using this approach and are being investigated as potential antimetabolites.

The reactivity of this T-shaped perfluoronickelacyclopentane–NHC complex with Lewis- and Brønsted acids is enhanced vs. 4-coordinate variants by its low coordination number.

The transition to more economically friendly small-chain fluorinated groups is leading to a resurgence in the synthesis and reactivity of fluoroalkenes. One versatile method to obtain a variety of commercially relevant hydrofluoroalkenes involves the catalytic hydrodefluorination (HDF) of fluoroalkenes using silanes. In this work it is shown that copper hydride complexes of tertiary phosphorus ligands (L) can be tuned to achieve selective multiple HDF of fluoroalkenes. In one example, HDF of the hexafluoropropene dimer affords a single isomer of heptafluoro-2-methylpentene in which five fluorines have been selectively replaced with hydrogens. DFT computational studies suggest a distinct HDF mechanisms for L2CuH (bidentate or bulky monodentate phosphines) and L3CuH (small cone angle monodentate phosphines) catalysts, allowing for stereocontrol of the HDF of trifluoroethylene.

New coinage-metal heptafluoroisopropyl (L n Mhfip) complexes are synthesized from the metal fluoride and inexpensive hexafluoropropene (M = Ag, Cu; L = PPh 3 , 2,2,6,6tetramethylpiperidine (Htmp)). Reaction of the silver Htmp complex with a Ni dibromide complex led to efficient hfip transfer to afford L 2 NiBr(hfip) (L = 2-ethylpyridine). Treatment of the Nihfip complex with ZnPh 2 gave the corresponding L 2 NiPh(hfip) complexes, which were investigated for reductive elimination of PhCF(CF 3 ) 2 . Although the desired reductive elimination proved unsuccessful, addition of carbon monoxide to L 2 NiPh(hfip) effected an efficient heptafluoroisopropyl carbonylative crosscoupling. Further, while the silver complex does not undergo hfip transfer to organic electrophiles, the copper complex (phen)(PPh 3 )Cu(hfip) (3b) effectively transfers the hfip unit to various substrates. We investigated the scope of 3b with acid chlorides toward the synthesis of perfluoroisopropyl aryl ketones. Additionally, reaction conditions for hfip transfer to pfluorobenzyl bromide and p-fluorobenzaldehyde were identified. As a bonus, 3b was easily generated on a gram scale using commercially available copper hydride by taking advantage of a rapid hydrodefluorination to generate "Cu−F" in situ. Aspects of the observed reactivity are supported by DFT calculations.

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