Decarbonylative CC Bond‐Forming Reactions of Saccharins by Nickel Catalysis: Homocoupling and Cycloaddition

Abstract

Decarbonylation of saccharins by nickel catalysis enables two kinds of CC bond-forming reactions; homocoupling of saccharins to form biaryls and cycloaddition with alkynes to form benzosultams. The former represents the first reported nickel-catalyzed decarbonylative CC homocoupling reaction, whereas the latter constitutes a powerful method to pharmaceutically relevant benzosultams. The reactions proceed with good functional-group tolerance and excellent regioselectivity.

Transition-Metal-Free Tandem Cyclization/N-Arylation Reaction: A Method To Access Biaryl Sultam Derivatives via a Diradical Pathway

“…The facile synthesis via the C–H functionalization catalyzed by Rh, Co, and Pd complexes with simple substrates has dominated in this field over the past decade. Transition-metal catalysis associated with the intermolecular cyclizations through a bond cleavage by the oxidative addition or the intramolecular cyclizations through a C–N bond formation has also demonstrated the feasibility to form diverse sultam derivatives. Meanwhile, the photoinduced radical annulations were reported mainly for the construction of biaryl sultams .…”

Visible Light Induced Bifunctional Rhodium Catalysis for Decarbonylative Coupling of Imides with Alkynes

“…A high yield was also obtained at lower catalyst loadings (1.0 mol %) with a prolonged reaction time (entry 15). Notably, other commonly used transition‐metal catalysts for decarbonylation, such as Ni(COD) 2 , [9a–d,g] Co 2 (CO) 8 , [18] Pd(PPh 3 ) 4 , [8] did not afford any desired product, which indicates the unique property of Rh in the photo‐induced decarbonylative reactions (entries 16–18).…”

Selective Decarbonylation via Transition-Metal-Catalyzed Carbon–Carbon Bond Cleavage

“…In addition to phthalimides, decarbonylative cycloaddition has also been achieved by using saccharins as the substrate. In 2015, Bi et al reported the Ni-catalyzed decarbonylative cycloaddition between saccharins 250 and alkynes 169 (Scheme 96); 254 decarbonylative homocoupling was also developed in this work. Mechanistically, the oxidative addition of Ni and extrusion of CO were key steps for both procedures.…”