Catalytic Decarboxylative C−N Formation to Generate Alkyl, Alkenyl, and Aryl Amines

Abstract

Transition-metal-catalyzed sp 2 C À Nbond formation is ar eliable method for the synthesis of aryl amines.C atalytic sp 3 CÀNformation reactions have been reported occasionally, and methods that can realizeboth sp 2 and sp 3 CÀNformation are relatively unexplored. Herein, we address this challenge with amethod of catalytic decarboxylative C À Nformation that proceeds through ac ascade carboxylic acid activation, acyl azide formation, Curtius rearrangement and nucleophilic addition reaction. The reaction uses naturally abundant organic carboxylic acids as carbon sources,r eadily prepared azidoformates as the nitrogen sources,a nd 4-dimethylaminopyridine (DMAP) and Cu(OAc) 2 as catalysts with as lowa s 0.1 mol %loading, providing protected alkyl, alkenyl and aryl amines in high yields with gaseous N 2 and CO 2 as the only byproducts.E xamples are demonstrated of the late-stage functionalization of natural products and drug molecules, stereospecific synthesis of useful a-chiral alkyla mines,a nd rapid construction of different ureas and primary amines.

N‐Atom Deletion in Nitrogen Heterocycles

“…For N‐heterocycles used in this reaction, one N‐substituent must be benzhydryl, or both N‐substituents must bear stabilizing elements such as benzyl, allyl or be positioned α to a carbonyl group. Inspired by our previous work, [13, 16] herein we report a N‐atom deletion of N‐heterocycles via a sequence of N ‐sulfonylazidonation, Curtius‐type rearrangement and subsequent rearrangement of the 1,2‐diazene intermediate, providing a unique opportunity to promote ring contraction [17] of N‐heterocycles (Scheme 1 F).…”

N‐Atom Deletion in Nitrogen Heterocycles

“…For Nheterocycles used in this reaction, one N-substituent must be benzhydryl, or both N-substituents must bear stabilizing elements such as benzyl, allyl or be positioned a to a carbonyl group. Inspired by our previous work, [13,16] herein we report a N-atom deletion of N-heterocycles via a sequence of Nsulfonylazidonation, Curtius-type rearrangement and subsequent rearrangement of the 1,2-diazene intermediate, providing a unique opportunity to promote ring contraction [17] of Nheterocycles (Scheme 1 F).…”

Construction of Benzenesulfonamide Derivatives via Copper and Visible Light-induced Azides and S(O)2–H Coupling

“…Therefore, reactions with new types of mechanisms for the preparation of sulfonamides are highly desirable. Inspired by previous research on using aryl azides as amino sources [ 11 ], we here develop a S(O) 2 –N coupling between S(O) 2 –H compounds and aryl azides by dual copper and photoredox catalysis [ 12 , 13 , 14 , 15 ]. This reaction produces sulfonamide compounds under mild redox-neutral conditions, which is efficient and mechanistically different from the nitrogen nucleophilic substitution reactions ( Scheme 1 c).…”