Andrew ratz Daphniphyllum Alkaloids Evans Group Seminar, June 1993 Retrosynthesis of Daphnilactone A Synthesis of Daphnilactone A LDA, homogeranyliodide 1. LAH 3.H3O+ Zn, THF, HMPA 100% Ang. Chem. Int J. Org. Chem. 1992, 57, 2585 32D-0812110011:51AMAndrew Ratz Daphniphyllum Alkaloids Evans Group Seminar, June 1993 Retrosynthesis of Daphnilactone A J. Org. Chem. 1992, 57, 2585 Angew. Chem. Int. Ed. Engl. 1992, 31, 665 O O iPr N Me CO2H HN Me iPr HN iPr Me OH HN Me iPr O O N Me Me Me Me Me Me O O O O O Br Br O Me Me Me EtO EtO2C Me Me Me CO2Et OEt 3. H3O+ Synthesis of Daphnilactone A : 1 + DIBAL tol. ∆ 87% H2, Pt 100% 1. Swern 2. NH3 3. HOAc, ∆ 87% LAH 90% Zn, THF, HMPA 89% 95% 1. LAH 2. LDA, homogeranyliodide 85% 4.5 Org. React. 1975, 22, 423 Ang. Chem. Int. Ed. Eng. 1967, 6, 1 Ang. Chem. Int. Ed. Eng. 1969, 8, 535 CO2Et OEt EtO EtO2C Me Me Me O O Br Br O Me Me Me Br COBr Br Me Me Me O O O O Br OZnBr O Me Me Me H HO O HO Me Me Me HN Me O HN Me iPr O HN iPr Me OH HO iPr HN Me 32D-08 12/11/00 11:51 AM