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The crystal and molecular structure of three derivatives of carbonyl 2-substituted pyrroles was determined by the single crystal X-ray diffraction. There are 2,2-dichloro-1-(1-methyl-1<i>H</i>-pyrrol-2-yl)ethan-1-one (<b>I</b>), 2-chloro-1-(1<i>H</i>-pyrrol-2-yl)ethan-1-one (<b>II</b>) and methyl 1<i>H</i>-pyrrole-2-carboxylate (<b>III</b>). All compounds crystallize with one molecule in the asymmetric unit in <i>P</i>2₁2₁2₁ for <b>I</b> and <b>II</b>, and <i>P</i>2₁/c group for <b>III</b>. Despite the similar structures of the investigated compounds, the hydrogen bonds formed in their crystal structures adopt different H-bond motifs. In structure <b>I</b>, the dimers R₁²(5) and R₂¹(7) form a chain along the <i>b</i>-axis, while in structures <b>II</b> and <b>III</b>, chain C(5) structural motifs are formed. The <i>single point</i> calculations at a ωB97XD/6-311++G(d,p) level of theory indicate that systems with N-H⋯O bonds have greater interaction energies (are more stable) compared with systems featuring C-H⋯O/Cl bonds. A descriptive Hirshfeld analysis showed that the greatest differences are visible for the H⋯H interactions. These H⋯H interactions predominate in structure <b>III</b>, accounting for 45% of the intermolecular interactions, while in structures <b>I</b> and <b>II</b>, they account for only 25%. Although compounds <b>I</b>-<b>II</b> contain Cl-atoms, the percentage of Cl⋯Cl interactions is rather low. In structure with two Cl-atoms (<b>I</b>), the contribution of the Cl⋯Cl contacts is 8.7% and for <b>II</b>, the contribution accounts for only 0.4% of the interactions.