1334849-09-0Relevant articles and documents
Synthesis of activated cyclopropanes by an MIRC strategy: An enantioselective organocatalytic approach to spirocyclopropanes
Russo, Alessio,Meninno, Sara,Tedesco, Consiglia,Lattanzi, Alessandra
, p. 5096 - 5103 (2011)
An efficient cyclopropanation, by a Michael-initiated ring-closing (MIRC) reaction of 2-arylidene-1,3-indandiones and 2-arylidene malononitriles, has been developed by using different α-monohalogenated methylene active compounds with triethylamine. The first enantioselective cyclopropanation to spirocyclopropanes derived by the reaction of 2-arylidene-1,3-indandiones and dimethyl bromomalonate with a commercially available α,α-L- diarylprolinol as the organocatalyst and K2CO3 as the additive has been accomplished. The spirocyclopropanes were isolated in high yield and up to 85% ee. Notably, the asymmetric one-pot sequential approach to spirocyclopropanes proved to be a feasible process. A simple triethylamine-promoted domino cyclopropanation of 2-arylidene-1,3-indandiones and 2-arylidenemalononitriles with α-monohalogenated methylene-active compounds has been efficiently developed. Spirocyclopropanes derived from 2-arylidene-1,3-indandiones were synthesized with up to 85% ee by using dimethyl bromomalonate and α,α-L-diarylprolinol/K2CO3 system. Copyright
