Enantioselective Total Synthesis of (-)- and (+)-Petrosin

The enantioselective total synthesis of (-)- and (+)-petrosin is described. The union of two key segments was executed by Suzuki Miyaura coupling. The quinolizidine rings were stereoselectively constructed via a diastereoselective Mannich reaction and an aza-Michael reaction. The 16-membered ring was constructed by ring-closing metathesis with the second-generation Grubbs catalyst.