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Crystals of tert‐butyl (2S)‐2‐(prop‐2‐yn‐1‐ylcarbamoyl)pyrrolidine‐1‐carboxylate (Boc‐L‐Pro‐NHCH₂CCH) have been obtained. The title compound crystallizes easily as sharp needles in orthorhombic system, space group P 2₁ 2₁ 2₁ with a = 9.2890(2), b = 9.7292(2), c = 15.7918(4) Å, V = 1427.18(6) ų, and Z = 4. The main feature of the structure is the orientation of the carbamate and amide. Their dipoles add up and the molecule displays an electric dipole moment of 5.61 D from B3LYP/6‐31G(d) calculations. The antiparallel H bonding of amides and the alignment of dipoles induce columnar stacking (the dipole moment along the columnar a axis is 4.46 D for each molecule). The other components across the other axes are, therefore weaker, (3.17 D and 1.23 D along the b and c axes, resp.). The resulting anisotropic columns pack side by side, in an antiparallel fashion mostly by (alkyne) CH···O=C …