[GRAPHICS] Propargylic 1,2-anti-diol derivatives 2 and 10 are prepared in high yield and excellent diastereoselectivity by addition of alpha -alkoxypropargyl-stannanes 4a and 4b to aldehydes in the presence of BuSnCl3. We also introduce the use of KF on Celite as a convenient and mild reagent for removal of the organotin waste products of these reactions.