This chiral phosphine, also known as (R)-(−)-5,5′-Bis[di(3,5-di-tert-butyl-4-methoxyphenyl)phosphino]-4,4′-bi-1,3-benzodioxole, presents as a white to almost white crystalline powder. Keep container tightly closed and in a cool and dark place. Store under inert gas and away from incompatible materials. This substance is Air-sensitive. (R)-(-)-DTBM-SEGPHOS is incompatible with oxidizing agents.