Copper-Catalyzed [4+2]-Cycloadditions of Isoxazoles with 2-Alkynylbenzaldehydes To Access Distinct α-Carbonylnaphthalene Derivatives: C(3,4)- versus C(4,5)-Regioselectivity at Isoxazoles was written by Giri, Sovan Sundar;Liu, Rai-Shung. And the article was included in ACS Catalysis in 2019.Name: 5-Chloro-2-(phenylethynyl)benzaldehyde The following contents are mentioned in the article:
Cu(II)-catalyzed [4+2]-cycloadditions occur between Cu-benzopyryliums and substituted isoxazoles with the regioselectivity on the C(3,4)-carbons of isoxazoles. We postulate that a prior coordination of isoxazoles with Cu(OAc)2 increases the π-bond character of the C(3,4) carbons to become an effective 2π-donor. In this reaction sequence, 3,5-disubstituted isoxazoles yield α,γ-dicarbonylnaphthalenes whereas, 5-substituted isoxazoles deliver α,γ-dicarbonyl-β-aminonaphthalenes. For unsubstituted isoxazole, its cycloaddition chemoselectivity is switched to the C(4,5)-addition regioselectivity to yield α-carbonyl-γ-cyanonaphthalene derivatives This study involved multiple reactions and reactants, such as 5-Chloro-2-(phenylethynyl)benzaldehyde (cas: 1186603-47-3Name: 5-Chloro-2-(phenylethynyl)benzaldehyde).
5-Chloro-2-(phenylethynyl)benzaldehyde (cas: 1186603-47-3) belongs to organic chlorides. Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. Alkanes and aryl alkanes may be chlorinated under free radical conditions, with UV light. However, the extent of chlorination is difficult to control.Name: 5-Chloro-2-(phenylethynyl)benzaldehyde
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics