Photoredox relay-catalyzed gem-difluoroallylation of alkyl iodides

Abstract

Herein, a new example of relay catalysis, using a combination of Mn2(CO)10 and an iridium-based photocatalyst, is reported. In our relay catalytic reaction, the Mn catalyst and iridium-based photocatalyst catalyze...

Recent Advances in C-F Bond Cleavage Enabled by Visible Light Photoredox Catalysis

“…Presumably due to the low BDE of the C-I bond, α-aminoalkyl radicals might undergo fast XAT with alkyl iodides prior to trapping by α-trifluoromethyl styrenes. Subsequently, Wang also reported the same reaction using Mn 2 (CO) 10 as the XAT catalyst and 4-phenyl Hantzsch ester (HE) as the reducing reagent (Scheme 33b) [82]. Molander reported the first defluorinative arylation of trifluoromethyl alkenes, in which aryl radicals were generated from aryl halides with tris(trimethylsilyl)silanol (TMS3SiOH) as the XAT reagent (Scheme 34) [83].…”

Defluorinative Alkylation of Trifluoromethyl Alkenes with Soft Carbon Nucleophiles Enabled by a Catalytic Amount of Base

“…Meanwhile, catalytic variants by virtue of transition metals, [6] photoredox, [7] and electrochemical [8] technique were also described to enable the incorporation of diversified functional groups attached to gem ‐difluoroalkenes through β‐F elimination of TAs. In the historical context of synthesizing alkyl substituted gem ‐difluoroalkenes, existing protocols usually relied on the pre‐functionalized alkyl group progenitors as the coupling partners, such as halides, [6c,i,j,7f–i,8a,b] acetals, [6d] oxime ethers, [6e,7e] carboxylates, [6h,7b–d,8c] trifluoroborates, [7a] etc (Figure 1a). Notwithstanding these achievements, the exploration of efficient and operationally mild strategies that avoid the use of organometallic reagents, strong bases, and transition metals, and install a densely functionalized alkyl group to gem ‐difluoroalkenes that permits further elaborations is highly sought‐after.…”

Ni-Catalyzed Radical-Promoted Defluoroalkylborylation of Trifluoromethyl Alkenes To Access gem-Difluorohomoallylic Boronates

“…α-Haloboronates are multifunctional synthons in organic chemistry that provide direct access to diverse valuable and complex alkylboronates . Moreover, protocols of radical addition to α-trifluoromethyl alkenes for providing gem -difluorovinyl compounds have been well-developed. , Inspired by these results and our previous efforts on fluorine-containing organoboron chemistry, here, we disclose an efficient strategy for the construction of gem -difluorohomoallylic boronates through a Ni-catalyzed radical-promoted defluoroalkylborylation of α-trifluoromethyl alkenes with α-haloboronates under mild conditions (Scheme d).…”