110969-44-3Relevant articles and documents
Aryl Amination Using Soluble Weak Base Enabled by a Water-Assisted Mechanism
Lau, Sii Hong,Yu, Peng,Chen, Liye,Madsen-Duggan, Christina B.,Williams, Michael J.,Carrow, Brad P.
supporting information, p. 20030 - 20039 (2021/01/01)
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 intramolecular N-H heterolysis. This water-assisted pathway operates efficiently with even weak terminal bases, such as Et3N. The use of a simple, commercially 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.
ORGANIC REACTIONS CARRIED OUT IN AQUEOUS SOLUTION IN THE PRESENCE OF A HYDROXYALKYL(ALKYL)CELLULOSE OR AN ALKYLCELLULOSE
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Page/Page column 217; 222; 223, (2017/08/21)
The present invention relates to a method of carrying out an organic reaction in aqueous solution in the presence of a hydroxyalkyl(alkyl)cellulose or an alkylcellulose.
Installation of protected ammonia equivalents onto aromatic & heteroaromatic rings in water enabled by micellar catalysis
Isley, Nicholas A.,Dobarco, Sebastian,Lipshutz, Bruce H.
supporting information, p. 1480 - 1488 (2014/03/21)
A single set of conditions consisting of a palladium catalyst, a commercially available ligand, and a base, allow for several types of C-N bond constructions to be conducted in water with the aid of a commercially available "designer" surfactant (TPGS-750-M). Products containing a protected NH2 group in the form of a carbamate, sulfonamide, or urea can be fashioned starting with aryl or heteroaryl bromides, iodides, and in some cases, chlorides, as substrates. Reaction temperatures are in the range of room temperature to, at most, 50 °C, and result in essentially full conversion and good isolated yields.
