Putting the Key pieces together 86 THE. -78C 2. PPTS MeOH 25C OTPS 2. Ph SnH, CH2,110 85% overall)Putting the Key Pieces Together O O O O O O O Me H H H H H H Me H Me H H Me Me Me A B C D E F G OTMS PPh3 I O O O H H OTBS EtS H Me I EtS H H O J K OTPS 1. n-BuLi, HMPA, THF, -78 oC 2. PPTS, MeOH, 25 oC (75% overall) O O O O O O O O O O OTPS Me H H H H H H Me H H H TBSO H Me H H Me Me EtS H Me Me A B C D E F G I J K EtS HO O O O O O O O O O O O OTPS Me H H H H H H Me H H H TBSO H Me H H Me Me H H H Me Me A B C D E F G H I J K 85 86 87 1. AgClO4, NaHCO3, SiO2, 4 A mol. sieves, CH3NO2, 25 oC 2. Ph3SnH, AIBN, PhCH3, 110 oC (85% overall) 161