Abstract:
Calix [4]bis(spirodienones) can perform as either 4 pi or 2 pi components in cycloaddition reactions with various carbo- and heterodienophiles and with 1,2-benzoquinones leading to the formation of highly functionalized macrocycles. In this Letter we report, highly regio- and stereoselective 1,3-dipolar cycloaddition reactions of a bis(spirodienone) derivative of calix[4]arene with nitrones that provide easy access to isoxazolidine derived macrocycles in excellent yields. These isoxazolidine derivatives can be considered as direct precursors of 1,3-amino alcohols.