Electrochemical C−H/N−H Activation by Water‐Tolerant Cobalt Catalysis at Room Temperature

Abstract

Electrochemistry enabled C-H/N-H functionalizations at room temperature by external oxidant-free cobalt catalysis. Thus, the sustainable cobalt electrocatalysis manifold proceeds with excellent levels of chemoselectivity and positional selectivity, and with ample scope, thus allowing electrochemical C-H activation under exceedingly mild reaction conditions at room temperature in water.

Electrochemical C−H Amination by Cobalt Catalysis in a Renewable Solvent

“…Among as et of representative solvents (entries 1-6), renewable g-valerolactone (GVL) provided the optimal results (entry 6). Therobustness of the scalable [6] electrocatalysis was reflected by ac omparable efficacyu nder an atmosphere of ambient air (entries 10 and 11). KOAc proved to be the ideal additive (entries 6-9), thus highlighting the importance of carboxylate [13] assistance for the electrochemical C À Hamination.…”

“…[1] Currently applied strategies for aniline syntheses heavily exploit metal-catalyzed cross-coupling reactions of organic electrophiles. [5] In sharp contrast, within our program on electrochemical CÀHactivation, [6] we have uncovered the first oxidative organometallic CÀH amination [7] that utilizes cheap and sustainable electricity [8] as the terminal oxidant, thus leading to H 2 as the sole byproduct. Am ore step-economical approach towards aromatic amines makes use of the direct amination of otherwise unreactive CÀHb onds, [3] thus avoiding the use of prefunctionalized aryl halides.…”

“…Am ore step-economical approach towards aromatic amines makes use of the direct amination of otherwise unreactive CÀHb onds, [3] thus avoiding the use of prefunctionalized aryl halides. [5] In sharp contrast, within our program on electrochemical CÀHactivation, [6] we have uncovered the first oxidative organometallic CÀH amination [7] that utilizes cheap and sustainable electricity [8] as the terminal oxidant, thus leading to H 2 as the sole byproduct. [5] In sharp contrast, within our program on electrochemical CÀHactivation, [6] we have uncovered the first oxidative organometallic CÀH amination [7] that utilizes cheap and sustainable electricity [8] as the terminal oxidant, thus leading to H 2 as the sole byproduct.…”

Synthesis of N‐Heterocycles by Dehydrogenative Annulation of N‐Allyl Amides with 1,3‐Dicarbonyl Compounds

“…[9] Organic electrochemistry,w hich employs traceless electrons to achieve redox reactions, [10] has been increasingly studied for promoting dehydrogenative cross-coupling reactions. [11,12] In this context, we have recently developed aCp 2 Fe-catalyzed electrochemical method for the generation of C-radicals from 1,3-dicarbonyl compounds. [13] This method has enabled the synthesis of oxindoles by dehydrogenative cyclization reactions.…”

Rhodaelectrocatalysis for Annulative C−H Activation: Polycyclic Aromatic Hydrocarbons through Versatile Double Electrocatalysis

“…[7,8] Significant recent impetus was gained by the merger of electrocatalysis with organometallic C À Ha ctivation, thus avoiding the use of toxic and expensive metal oxidants. [9,10] While electrochemical polymerization has been exploited for the synthesis of conducting materials, [11] the bottom-up assembly of atomically precise PA Hm otifs by electrooxidative catalysis has thus far unfortunately proven elusive.I n sharp contrast, we have now devised an ovel strategy for merging two distinct electrocatalytic transformations for the chemoselective assembly of decorated PA Hs.T he development of an unprecedented rhodaelectrocatalyzed [12] C À H activation for the annulative [13] [2+ +2+ +2] cycloaddition of userfriendly boronic acids set the stage for an electro-catalyzed dehydrogenation in ar esource-economical manner ( Figure 1). Salient features of our method include 1) rapid, modular access to PA Hs through double electrocatalysis, 2) electricity as as ustainable oxidant, 3) the formation of six new C À Cb onds in ap rogrammable fashion, and 4) outstanding levels of chemoselectivity through metallaelectrocatalysis.…”