Studies on the syntheses of heterocyclic compounds. 800. A formal total synthesis of (.+-.)-thienamycin and a (.+-.)-decysteaminylthienamycin derivative
Synthesis of trans-3-(1'R*-hydroxyethyl)-4-(2',2'-dimethoxyethyl)-2-azetidinone (5), an important intermediate for the synthesis of thienamycin (1), was investigated starting from the isoxazoline derivatives 3 and 9. The most effective method was catalytic hydrogenation of trans-4-t-butoxycarbonyl-3-(2,2'-dimethoxyethyl)-5-methyl-isoxazoline (9) with Adams catalyst in acetic acid, followed by trimethylsilylation