Catalyst‐Free Reductive Coupling of Aromatic and Aliphatic Nitro Compounds with Organohalides

Abstract

Ar are reductive coupling of nitro compounds with organohalides has been realized. The reaction is initiated by ap artial reduction of the nitro group to an itrenoid intermediate.T herefore,n ot only aromatic but also aliphatic nitro compounds are efficiently transformed into monoalkylated amines,w ith organohalides as the alkylating agent. Given the innate reactivity of the nitrenoid, ac atalyst is not required, resulting in ahigh tolerance for aryl halide substituents in both starting materials. Scheme 1. Reductivec oupling strategies. Table 2: Scope of the reductive coupling of nitro compounds with organohalides.Reaction conditions: Zn powder (4 equiv) and LiCl (2.2 equiv) were dried in vacuo, 1mLTHF was added, followed by pretreatment with catalytic amounts of TMSCl and dibromoethane. R 1 X 2 (0.6 mmol, 3equiv), the nitro compound 1 (0.2 mmol), and B 2 pin 2 (0.4 mmol, 2equiv) were added and the reaction was stirred for 12 hatRT. The aminoborane D was hydrolyzed by addition of water.[a] Carried out at 50 8 8C.[b] Reaction stirred for 1hat 50 8 8Cbefore the addition of 1a.[c] Carried out at 70 8 8C. Structures, compound numbers, and yields of isolatedproducts after column chromatography are given.

An Improved PIII/PV═O-Catalyzed Reductive C–N Coupling of Nitroaromatics and Boronic Acids by Mechanistic Differentiation of Rate- and Product-Determining Steps

“…Knochel and Kürti have demonstrated the use of excess Grignard reagents to convert nitroarenes to N -arylanilines directly. Niggemann has found that the combination of nitroarenes with organozinc reagents in the presence of stoichiometric B 2 pin 2 results in reductive conversion to N-functionalized anilines . Recent works from our group and Csákÿ have validated a stoichiometric, phosphine-mediated reductive coupling of nitroarenes and arylboronic acids.…”

Aluminum Metal–Organic Framework–Silver Nanoparticle Composites for Catalytic Reduction of Nitrophenols

“…Nitroaromatics, such as isomers and homologues of nitrophenols, are persistent pollutants of emerging concerns due to their toxicity, non-biodegradability, and carcinogenicity. 1,2 Due to their wide industrial use, the disposal of nitrophenols causes health problems to human beings and severe damages to the environment. 3−5 Moreover, soluble nitrophenols can only be removed with difficulties through a conventional wastewater treatment process.…”

Intermediate formation enabled regioselective access to amide in the Pd-catalyzed reductive aminocarbonylation of olefin with nitroarene

“…Nitroarenes are generally cheaper, more readily available, and more functionally compatible than anilines as nitrogen sources [1][2][3][4]. Therefore, using nitroarenes as starting molecules is advantageous for preparing nitrogen-containing functional molecules in proper cascade reactions [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”