Catalyst-Free α--Selective Hydroboration and ()-Selective Deuterated Semihydrogenation of Alkynyl Sulfones.

Here, we present a straightforward α--selective hydroboration of alkynyl sulfones with NHC-boranes without the need for a catalyst. This reaction is compatible with a wide range of substrates for efficiently producing structurally diverse α-borylated vinyl sulfones in satisfactory yields. The hydride transfer from NHC-borane to alkynyl triflone is studied by density functional theory (DFT) calculations for -hydroboration.

Visible-Light-Initiated Sequential Trifluoromethylation/Remote C(sp)-H Alkynylation of Vinyl Azides by Radical Relay.

A visible-light-initiated trifluoromethylation/remote aliphatic C-H alkynylation of α-alkyl-substituted vinyl azides using acetylenic triflones as both the trifluoromethyl and alkyne donors is described. The reaction occurred under environmentally benign and radical initiator-free reaction conditions, affording γ-alkynylated trifluoromethyl ketone derivatives with a broad scope of substituents. Mechanistic studies suggested that the reaction is initiated a triplet-triplet energy transfer between the 4CzIPN catalyst and acetylenic triflone, followed by fragmentation to generate a trifluoromethyl radical and an alkynyl radical.