Efficient synthesis of functionalized chromones via a two-base mediated formal [3+3] cycloaddition was written by Dong, Qian;Shen, Hong C.;Jiang, Min. And the article was included in Tetrahedron Letters in 2016.Synthetic Route of C9H10O3S This article mentions the following:
An efficient one-pot synthesis of functionalized chromones from ketone derivatives and o-haloaroyl chlorides was achieved using a combination of two bases under transition-metal-free conditions. This formal [3+3] cycloaddition consists of a sequential C-acylation and O-arylation, which is amenable to a broad range of substrates leading to diversely functionalized chromones in moderate to high yields. Notably, the utility of this methodol. was demonstrated by a two-step concise synthesis of frutinone A. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Synthetic Route of 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. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Synthetic Route of C9H10O3S
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics