The title compound, C(24)H(30)N(2)O(4), was obtained by the reaction of (2R,6S)-4-(tert-but-oxy-carbon-yl)-6-methyl-morpho-line-2-carb-oxy-lic acid with diphenyl-methanamine in dimethyl-formamide solution. The morpholine ring is in a chair conformation. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into chains along the b axis.