%0 Journal Article %J Chemistryselect %D 2017 %T Formal [2+1] annulation (Spiro-Cyclopropanation) reaction between sulfur ylides derived from baylis-hillman bromides and arylidene indane-1,3-dione %A Roy, Suparna %A Piradhi, Venkatesh %X

The sulfonium salts derived from the Baylis-Hillman bromides have been successfully employed for the selective cycloproporanation of arylidene indane-1,3-diones to synthesize densely substituted spiro-cyclopropanes in good to excellent yields (upto 94%). Products were obtained mostly in 1:1 diastereomeric ratio and were isolated in pure form. Diastereoselectivity has been improved by using suitably substituted starting materials. In this case a formal [2+1] annulation reaction competes over a probable [3+2] cycloaddition reaction. The reaction proceeds through a Michael initiated ring closure process of S-ylides to the activated olefins for the formation of structurally strained spiro-cyclopropanes.

%B Chemistryselect %V 2 %P 6159-6162 %8 JUL %G eng %N 21 %9 Article %3

Foreign

%4 1.505 %R 10.1002/slct.201701221