《Aryl Amination Using Soluble Weak Base Enabled by a Water-Assisted Mechanism》 was published in Journal of the American Chemical Society in 2020. These research results belong to Lau, Sii Hong; Yu, Peng; Chen, Liye; Madsen-Duggan, Christina B.; Williams, Michael J.; Carrow, Brad P.. Safety of tert-Butyl carbamate The article mentions the following:
The amination of aryl halides has become one of the most commonly practiced C-N bond-forming reactions in pharmaceutical and laboratory syntheses. The widespread use of strong or poorly soluble inorganic bases for amine activation nevertheless complicates the compatibility of this important reaction class with sensitive substrates as well as applications in flow and automated synthesis, to name a few. We report a palladium-catalyzed C-N coupling using Et3N as a weak, soluble base, which allows a broad substrate scope that includes bromo- and chloro(hetero)arenes, primary anilines, secondary amines, and amide type nucleophiles together with tolerance for a range of base-sensitive functional groups. Mechanistic data have established a unique pathway for these reactions in which water serves multiple beneficial roles. In particular, ionization of a neutral catalytic intermediate via halide displacement by H2O generates, after proton loss, a coordinatively unsaturated Pd-OH species that can bind amine substrate triggering intramol. N-H heterolysis. This water-assisted pathway operates efficiently with even weak terminal bases, such as Et3N. The use of a simple, com. available ligand, PAd3, is key to this water-assisted mechanism by promoting coordinative unsaturation in catalytic intermediates responsible for the heterolytic activation of strong element-hydrogen bonds, which enables broad compatibility of carbon-heteroatom cross-coupling reactions with sensitive substrates and functionality. The results came from multiple reactions, including the reaction of tert-Butyl carbamate(cas: 4248-19-5Safety of tert-Butyl carbamate)
tert-Butyl carbamate(cas: 4248-19-5) belongs to anime. Amines characteristically form salts with acids; a hydrogen ion, H+, adds to the nitrogen. With the strong mineral acids (e.g., H2SO4, HNO3, and HCl), the reaction is vigorous. Salt formation is instantly reversed by strong bases such as NaOH. Neutral electrophiles (compounds attracted to regions of negative charge) also react with amines; alkyl halides (R′X) and analogous alkylating agents are important examples of electrophilic reagents.Safety of tert-Butyl carbamate
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