Recent advancements in iodide/phosphine-mediated photoredox radical reactions

• Tinglan Liu,
• Yu Zhou,
• Junhong Tang and
• Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

• ]. Importantly, these methodologies could also be smoothly extended to the synthesis of isoquinolinediones, which borne a quaternary carbon center. Furthermore, Yatham and his colleagues unveiled the first NaI/PPh3-mediated photocatalytic decarboxylative cascade cyclization of 2-isocyanobiaryls 44 with alkyl N

• ], it was proposed that the decarboxylative cascade cyclization reaction proceeded through the formation of a charge-transfer complex (CTC) II involving PPh3, NaI, and NHP ester 3 (Scheme 20). Upon photofragmentation of the CTC complex II, two important intermediates were generated: an alkyl radical A

NaI/PPh₃-catalyzed visible-light-mediated decarboxylative radical cascade cyclization of N-arylacrylamides for the efficient synthesis of quaternary oxindoles

• Dan Liu,
• Yue Zhao and
• Frederic W. Patureau

Beilstein J. Org. Chem. 2023, 19, 57–65, doi:10.3762/bjoc.19.5

• afforded various functionalized oxindoles featuring a C3 quaternary stereogenic center. Mechanistic experiments suggest a radical mechanism. Keywords: decarboxylative cascade cyclization; iodide catalysis; metal-free photocatalysis; oxindole; phosphine catalysis; Introduction Radical-initiated cascade

• this decarboxylative cascade cyclization process (Table 1, entries 19 and 20). With the optimized conditions in hand, we then explored the scope of N-arylacrylamides with different substituents. A series of acrylamides showed good compatibility under standard conditions, offering the desired oxindoles

• replacing the methyl with a phenyl group at the N-arylacrylamide core significantly affected the reaction efficiency from 72% to 34% yield (3pa). Satisfyingly, substrate 1q could successfully undergo decarboxylative cascade cyclization to afford 3qa with 70% yield, which is used as a key intermediate in the