Enantioselective Synthesis of Polysubstituted Benzopyrano[3,4-c]pyrrolidine Frameworks via [3 + 2] Cycloaddition of Azomethine Ylides and Coumarin Derivatives was written by Chang, Geng-Hua;Wang, Chein-Yi;Madhusudhan Reddy, G.;Tsai, Yi-Ling;Lin, Wenwei. And the article was included in Journal of Organic Chemistry in 2016.Formula: C9H10O3S This article mentions the following:
An enantioselective synthesis of benzopyrano[3,4-c]pyrrolidine derivatives via organocatalyzed [3 + 2] cycloaddition has been achieved. Cinchona alkaloid-derived organocatalysts as Bronsted bases have been examined for this asym. cycloaddition of o-hydroxy aromatic aldimines with 3-substituted coumarins. An unexpected rearrangement of the quaternary acyl moiety in the products resulted in an in situ protection of the o-hydroxy group. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Formula: C9H10O3S).
Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Formula: C9H10O3S
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics