Approach to the Synthesis of Nogalarol via the Cycloaddition of a Carbene-Chromium Complex with a Functionalized Alkyne.

Abstract The alkyne, 4 , prepared stereoselectively in 7 steps from acetyl furan, reacts with (methoxy)(phenyl)carbenepentacarbonylchromium(0), 15 , to give the model ( 16 ) for nogalarol ( 1b ) in 43% yield.