One Stone for Three Birds-Rhodium-Catalyzed Highly Diastereoselective Intramolecular [4+2] Cycloaddition of Optically Active Allene-1,3-dienes

Summary of main observation and conclusion RhCI(PPh3)3-catalyzed [4+2] intramolecular cycloaddition of optically active axially chiral allene-dienes afforded c/s-fused [3.4.0]-bicyclic products with three chiral centers in good yields with an excellent chemo-and diastereoselectivity. A pair of enantiomers of such products was gen erated highly selectively from both ena ntiomers of starting allene-die nes, indicati ng that the axial chirality dictated the absolute configurations of the three in situ generated chiral centers with a very high efficiency of chirality transfer.