This chiral auxiliary, also known as (S)-(-)-2-Methyl-2-propanesulfinamide, presents as a white to very pale-yellow crystalline powder. It is known to be soluble in methanol. Store in a tightly closed container in a cool and dark place, ideally at refrigerated temperatures. (S)-(-)-tert-Butylsulfinamide is incompatible with oxidizing agents.