(R)-(-)-Mandelic acid has been converted by stereospecific reactions into enantiomerically pure (R)-(+)-2-phenylethanol-2-d [Formual Omitted], (R)-(+)-2-phenylethanol-1, 1, 2-d3 [formula omitted], and the four (S)-(+)-deuteriophenylethanes prepared by replacing the hydroxyl groups of these 1-phenylethanols by hydrogen or deuterium. The optical rotation of (S)-(+)-l-phenylethane-7-d (PhCHDCHa, [a]20D +0.81 ± 0.01°, neat) was only slightly different than that of (S)-(+)-l-phenylethaxie-1, 2, 2, 2-d4 [Formula Omitted], while the corresponding di- and trideuterated analogues had the same rotation within experimental limits ([o]20d +0.80 ± 0.01°, neat). © 1979, American Chemical Society. All rights reserved.