The highly stereoselective conjugate addition of lithium (R)-(alpha-me
thylbenzyl)benzylamide (R)-2 to tert-butyl (E)-2-methyl-2-pentenoate 3
affords a-straightforward synthesis of (2S,3R)-2-methyl-3-aminopentan
oic acid 1 as its hydrochloride salt 5.