Asymmetric total syntheses of passifetilactones A, C, E and 4-epi-passifetilactone B
Sagar B Khandekar1, Naga Raju Barnala1, Rodney A Fernandes1
1Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, Maharashtra, India. rfernand@chem.iitb.ac.in.
Abstract:
This paper describes the efficient asymmetric total syntheses of passifetilactones A, C, E and 4-epi-passifetilactone B. Keck allylation and ring-closing metathesis (RCM) have been employed as the key steps in the synthesis of passifetilactones A and C, while Sharpless kinetic resolution (SKR) and RCM have been utilized in the syntheses of passifetilactone E and 4-epi-passifetilactone B. The total syntheses of passifetilactones A, C, E and 4-epi-passifetilactone B required 8, 4, 8 and 10 steps with good overall yields of 37.4%, 60%, 10.2% and 3.5%, respectively. The synthesis efforts also established the absolute structures of these molecules.
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