An Efficient Method for the Synthesis of Alkylidenecyclobutanones by Gold-Catalyzed Oxidative Ring Enlargement of Vinylidenecyclopropanes was written by Yuan, Wei;Dong, Xiang;Wei, Yin;Shi, Min. And the article was included in Chemistry – A European Journal in 2012.Electric Literature of C7H9NO This article mentions the following:
Alkylidenecyclobutanones, e.g., I, are prepared from vinylidenecyclopropanes, e.g., II, by a gold-catalyzed oxidative ring expansion. (Triphenylphosphine)gold chloride (5 mol%) and silver hexafluoroantimonate (10 mol%) in the presence of 3,5-dibromopyridine N-oxide (2 equiv) effected the transformation. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Electric Literature of C7H9NO).
3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Electric Literature of C7H9NO