17282-45-0Relevant articles and documents
Ultrasound-Promoted Synthesis of Spirocyclopropanes from Switchable Starting Materials via Azomethine Ylide [3+2]-Cycloaddition
Yavari, Issa,Sheikhi, Sara,Sheykhahmadi, Jamil,Taheri, Zohreh,Halvagar, Mohammad Reza
, p. 2057 - 2066 (2021)
An ultrasound-promoted green protocol to access a new series of spirocyclopropanes from indeno[1,2- b ]quinoxaline derivatives and azomethine ylides, generated in situ from the iodine-catalyzed reaction of acetophenones as well as of 2-methylquinoline with pyridine in the presence of a base, is described. These transformations proceed via a spirocyclopropanation reaction followed by elimination of pyridine. Clear evidence for the structure of a spirocyclopropane-linked indenoquinoxaline derivative was obtained from single-crystal X-ray analysis. The most important feature of this reaction is the fact it forms three stereogenic centers, one of which is quaternary, with excellent selectivity.