Preparative Scale Synthesis of Functionalized Bioxazole

Seven-step preparative scale synthesis of chiral, enantiomerically pure 2'-aminomethyl-2,4'-bioxazole has been accomplished from L-tert-Leu. The 2,4'-bioxazole subunit can be functionalized at position C-5' by a regioselective lithiation, followed by the reaction with a suitable electrophile. The C-5'-lithium intermediate can be also transmetalated into organozinc species and used in Pd-catalyzed Negishi cross coupling.