2003 Terpenes

TerpenesU 0200 A Tandem Metal Carbene Cyclization—Cycloaddition Approach to the Pseudola-

ric Acids. — The synthesis of key intermediate (V) of Pseudolaric acids is achieved via tandem cyclization-cycloaddition of the diazo ketone (V). The outcome of this re-action is found to depend on the nature of C-3 substituent and catalyst used. Addition-ally, ring-opening of the oxabicyclic ring system is studied. The model compound (VIII) gives good results. — (CHEN, B.; KO, R. Y. Y.; YUEN, M. S. M.; CHENG, K.-F.; CHIU*, P.; J. Org. Chem. 68 (2003) 11, 4195-4205; Dep. Chem., Univ., Hong Kong, Peop. Rep. China; Eng.) — Jannicke

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