Modified Julia olefination and α aminoxylation reactions mediated convergent synthesis of 1α, 24 (R)-dihydroxyvitamin D3 (tacalcitol)

Abstract A convergent synthesis of tacalcitol has been achieved starting from inexpensive and commercially available isovaleraldehyde and easily available Inhoffen-Lythgoe diol. Key steps include a proline catalyzed α aminoxylation and a Julia-Kocienski olefination.