Scandium(III) Trifluoromethanesulfonate Catalyzed Reactions of Donor‐Acceptor Cyclopropanes with 1,1‐Diarylethylenes

Abstract

A Lewis acid-promoted DÀ A cyclopropane reacting with 1,1diarylethylenes was developed. This reaction features mild reaction conditions, easy availability of starting materials, good functional group tolerance and high yields (up to 91%).Moreover, substituent effects on product distribution were observed. The scenario of the reaction pathway was supposed to involve the Sc(OTf) 3 -mediated ring-opening 1,3-dipole intermediate followed by the attack of 1,1-diarylethylenes.available donor-acceptor cyclopropanes as versatile reagents. Efforts to develop conditions for the enantioselective reactions of donor-acceptor cyclopropanes, are currently underway. The robustness and practicality of the current method will be further demonstrated by other applications.

Three-Component GaHal3-Promoted Reactions of Substituted Methylidenemalonates and Donor–Acceptor Cyclopropanes with Propargyl Halides: Cascade Diastereoselective Construction of Five-Membered Lactones

“…Donor–acceptor alkenes (DAAs) and cyclopropanes (DACs) are extremely popular in organic synthesis. − A combination of two electron-withdrawing ester groups with various electron-donating substituents is often used to activate a double bond or a cyclopropane ring in these syntheses. − Owing to the availability of two ester groups, it is very convenient to activate such substrates by various Lewis acids and use them in various reactions. Accordingly, substituted methylidenemalonates 1 or cyclopropanedicarboxylates 2 are used as the DAAs or DACs , in these cases.…”