The critical parameters of pyridine are pressure 6.70 MPa, temperature 620 K and volume 229 cm3·mol−1. 31181-90-5, formula is C6H4BrNO, Name is 5-Bromopicolinaldehyde. In the temperature range 340–426 °C its vapor pressure p can be described with the Antoine equation.. Electric Literature of 31181-90-5.
Rajkiewicz, Adam A.;Wojciechowska, Natalia;Kalek, Marcin research published 《 N-Heterocyclic Carbene-Catalyzed Synthesis of Ynones via C-H Alkynylation of Aldehydes with Alkynyliodonium Salts – Evidence for Alkynyl Transfer via Direct Substitution at Acetylenic Carbon》, the research content is summarized as follows. Alkynylation of aldehydes with alkynyl(aryl)iodonium salts catalyzed by an N-heterocyclic carbene has been developed. The application of the organocatalyst and the hypervalent iodine group-transfer reagent allowed for metal-free C-H functionalization and C-C bond formation. The reaction proceeds under mild conditions, at -40° and in the presence of an amine base, providing access to an array of heteroaryl-propargyl ketones containing various substituents in good to excellent yields. The mechanism of the reaction was investigated by means of both experiments and d. functional theory calculations 13C-labeling and computations determined that the key alkynyl transfer step occurs via an unusual direct substitution at an acetylenic carbon, wherein an iodine-based leaving group is exchanged by a Breslow intermediate nucleophile. Moreover, kinetic studies revealed that the turnover-limiting step of the catalytic cycle is the generation of the Breslow intermediate, whereas the subsequent C-C bond-formation is a fast process. These results are fully reproduced and rationalized by the calculated full free energy profile of the reaction, showing that the largest energy span is located between the protonated form of NHC catalyst and the transition state for the carbene attack on the aldehyde substrate.
31181-90-5, 5-Bromopyridine-2-carbaldehyde is a useful research compound. Its molecular formula is C6H4BrNO and its molecular weight is 186.01 g/mol. The purity is usually 95%.
5-Bromopyridine-2-carbaldehyde is a water soluble organic molecule that has been shown to inhibit the mitochondrial respiratory chain. It is a structural analog of the natural substrate for mitochondrial cytochrome c oxidase, 5-aminolevulinic acid. This compound has been shown to be selective against cancer cells and has anti-viral properties. The photophysical properties of 5-bromopyridine-2-carbaldehyde have been studied extensively. The fluorescence quantum yield of this molecule in aqueous solution is 0.06%., Electric Literature of 31181-90-5