The author of 《Sequential Multicomponent Synthesis of 2-(Imidazo[1,5-α]pyridin-1-yl)-1,3,4-Oxadiazoles》 were Kurhade, Santosh; Konstantinidou, Markella; Sutanto, Fandi; Kurpiewska, Katarzyna; Kalinowska-Tluscik, Justyna; Doemling, Alexander. And the article was published in European Journal of Organic Chemistry in 2019. Formula: C4H5ClO3 The author mentioned the following in the article:
A 21 membered library of 2-(imidazo[1,5-α]pyridine-1-yl)-1,3,4-oxadiazoles is synthesized in an unprecedented short sequence starting from an Ugi tetrazole reaction with a cleavable isocyanide component. The intermediate tetrazole is subjected to an acetic anhydride-mediated cyclization, followed by a Huisgen-type rearrangement with acyl chlorides to afford the imidazopyridine-oxadiazole bis-heterocycles. The scope and limitations of the methodol. were investigated with substitutions on both the oxadiazole and the imidazopyridine rings. The introduced enabling technol. for imidazopyridine oxadiazole synthesis combines a short reaction sequence with high scaffold diversity, based on com. available starting materials and high functional groups tolerance. In the experiment, the researchers used many compounds, for example, Ethyl oxalyl monochloride(cas: 4755-77-5Formula: C4H5ClO3)
Ethyl oxalyl monochloride(cas: 4755-77-5) belongs to acyl chlorides. Lacking the ability to form hydrogen bonds, acyl chlorides have lower boiling and melting points than similar carboxylic acids. For example, acetic acid boils at 118 °C, whereas acetyl chloride boils at 51 °C. Like most carbonyl compounds, infrared spectroscopy reveals a band near 1750 cm−1.Formula: C4H5ClO3
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