Mc. Pirrung et Yr. Lee, DIPOLAR CYCLOADDITION OF RHODIUM CARBENOIDS WITH VINYL ESTERS - TOTALSYNTHESIS OF PONGAMOL AND LANCEOLATIN-B, Tetrahedron letters, 35(34), 1994, pp. 6231-6234
A new method for dipolar cycloaddition of diazocyclohexane-1,3-diones,
leading to benzofuran derivatives, has been applied to the total synt
hesis of natural products from Tephrosia and Pongamia.