626-61-9Relevant articles and documents
Selective formation of a single atropisomer of meso-meso-linked Zn II diporphyrin through supramolecular self-assembly
Maeda, Chihiro,Kamada, Taisuke,Aratani, Naoki,Sasamori, Takahiro,Tokitoh, Norihiro,Osuka, Atsuhiro
, p. 9681 - 9684 (2009)
One-way atropisomerism: ineso-(4-Butoxypyrid-3-yl)-substituted Zn II porphyrins self-assemble to form zigzagshaped cyclic hexamers, whereas the meso-meso-linked ZnII diporphyrins 1 undergo self-sorting self-assembly to form different assemblies. Upon heating, entropically driven one-way atropisomerism to 1in-in has been achieved through fragmentary reconstitution of supramolecular aggregates.
Deaminative chlorination of aminoheterocycles
Cornella, Josep,Faber, Teresa,Gómez-Palomino, Alejandro,Ghiazza, Clément
, (2021/12/23)
Selective modification of heteroatom-containing aromatic structures is in high demand as it permits rapid evaluation of molecular complexity in advanced intermediates. Inspired by the selectivity of deaminases in nature, herein we present a simple methodology that enables the NH2 groups in aminoheterocycles to be conceived as masked modification handles. With the aid of a simple pyrylium reagent and a cheap chloride source, C(sp2)?NH2 can be converted into C(sp2)?Cl bonds. The method is characterized by its wide functional group tolerance and substrate scope, allowing the modification of >20 different classes of heteroaromatic motifs (five- and six-membered heterocycles), bearing numerous sensitive motifs. The facile conversion of NH2 into Cl in a late-stage fashion enables practitioners to apply Sandmeyer- and Vilsmeier-type transforms without the burden of explosive and unsafe diazonium salts, stoichiometric transition metals or highly oxidizing and unselective chlorinating agents. [Figure not available: see fulltext.]
Efficient Chemoselective Reduction of N-Oxides and Sulfoxides Using a Carbon-Supported Molybdenum-Dioxo Catalyst and Alcohol
Li, Jiaqi,Liu, Shengsi,Lohr, Tracy L.,Marks, Tobin J.
, p. 4139 - 4146 (2019/05/27)
The chemoselective reduction of a wide range of N-oxides and sulfoxides with alcohols is achieved using a carbon-supported dioxo-molybdenum (Mo@C) catalyst. Of the 10 alcohols screened, benzyl alcohol exhibits the highest reduction efficiency. A variety of N-oxide and both aromatic and aliphatic sulfoxide substrates bearing halogens as well as additional reducible functionalities are efficiently and chemoselectively reduced with benzyl alcohol. Chemoselective N-oxide reduction is effected even in the presence of potentially competing sulfoxide moieties. In addition, the Mo@C catalyst is air- and moisture-stable, and is easily separated from the reaction mixture and then re-subjected to reaction conditions over multiple cycles without significant reactivity or selectivity degradation. The high stability and recyclability of the catalyst, paired with its low toxicity and use of earth-abundant elements makes it an environmentally friendly catalytic system.
