Fluorinative Beckmann Fragmentation: Fluorinative .ALPHA.-Cleavage of Cyclic Ketoximes by Diethylaminosulfur Trifluoride.

Photoinduced Remote Functionalisations by Iminyl Radical Promoted C−C and C−H Bond Cleavage Cascades

“…This represents aradical "abnormal" Beckmann fragmentation/fluorination process. [12] Control experiments confirmed the requirement for base, 2, and continuous blue-light irradiation. Aq uantum yield [13] of F = 2.8 was determined for this transformation, which suggests that productive short-lived radical chain propagation processes are operating together with the photoredox pathway.…”

Photoinduced Remote Functionalisations by Iminyl Radical Promoted C−C and C−H Bond Cleavage Cascades

“…However, by using H 2 O as the co‐solvent (entry 3) and K 2 CO 3 as the base (entry 4), 3 a was obtained in high yield in just 15 min. This represents a radical “abnormal” Beckmann fragmentation/fluorination process . Control experiments confirmed the requirement for base, 2 , and continuous blue‐light irradiation.…”

Diethylaminosulfurtrifluoride

“…Cyclic ketoximes that have carbocation-stabilizing substituents react with DAST to undergo Beckmann rearrangement to form fluorinated carbonitriles in good yields (Table 5). 79 Ketoximes that do not have carbocation-stabilizing substituents afford complex mixtures. 79 Reaction of DAST with various serine derivatives produced the peptides containing (E)-and (Z)-3-fluorodihydroaniline via a fluoro-Pummerer rearrangement (eq 30).…”

“…79 Ketoximes that do not have carbocation-stabilizing substituents afford complex mixtures. 79 Reaction of DAST with various serine derivatives produced the peptides containing (E)-and (Z)-3-fluorodihydroaniline via a fluoro-Pummerer rearrangement (eq 30). 80 Epoxy alcohols react with DAST to form monofluoro vinyl ethers via carbon-carbon bond cleavage (eq 31).…”