1,3-Diamine Formation from an Interrupted Hofmann–Löffler Reaction: Iodine Catalyst Turnover through Ritter-Type Amination

Abstract

An iodine-catalyzed Ritter-type amination of nonactivated C–H bonds is presented enabling the formation of 1,3-α-tertiary diamines. A sulfamidyl radical serves as the promoter in a guided tertiary C–H iodination through an exclusive 1,6-HAT process. The subsequent Ritter reaction furnishes the C–N bond and establishes an unprecedented concept for catalyst turnover in iodine redox catalysis. The general robustness of the methodology, including broad functional group tolerance, was demonstrated for 24 different 1,3-diamine derivatives, which were synthesized in yields of 42%–99%.

Visible Light‐Induced Intramolecular C─O Bond Formation via 1,5‐Hydrogen Atom Transfer Strategy

“…As expected, no product was obtained when the reaction was conducted without NIS or light irradiation (entries 9 and 13). In the absence of AcOH, the product yield was decreased (entry 10) 17,37 . Interestingly, the addition of catalytic amounts of I 2 led to the highest yield (entry 11).…”

Recent Applications of Ritter Reactions in Organic Syntheses

“…Compounds 91 were synthesized from the non‐classical Ritter reaction of acetonitrile 47 with sulfamidyl compounds 90 using I 2 as the catalyst and (diacetoxyiodo)banzane (PIDA) as the iodine(III) reagent at room temperature (Scheme 36). [48] …”

Photochemically-Mediated Nickel-Catalyzed Synthesis of N-(Hetero)aryl Sulfamides

“…1a In reactions, N,N'-disubstituted sulfamides are useful as chiral auxiliaries, 5 as organocatalysts, 6 as reagents to promote dehydration, 7 as precursors to sterically encumbered carbon-carbon bonds 8 and as directing groups for C-H functionalization processes. 9 Despite the potential of this valuable functional group, To date, approaches to prepare N-(hetero)aryl sulfamides rely on N-S bond-forming reactions that involve the nucleophilic addition of amines to SO2 sources (not depicted), 12,13 or on C-N bond-forming strategies (Scheme 1). These direct methods for C-N bond formation have been primarily limited to nucleophilic substitution reactions (Scheme 1A), copper-mediated Chan-Lam coupling processes that transform sulfamoyl azides (Scheme 1B), 14 and Buchwald-Hartwig amination conditions that are palladium-mediated (Scheme 1C).…”