6-(3-Chloro­phen­yl)imidazo[2,1-b][1,3,4]thia­diazole

In the title compound, C₁₀H₈ClN₃S, the dihedral angle between the mean planes of the benzene and imidazo[2,1-b][1,3,4]thia­diazole rings is 6.0 (9)°. In the crystal, mol­ecules are assembled by the formation of centrosymmetric dimers by π-stacking of the thia­diazole and benzene rings of neighboring mol­ecules [centroid–centroid distance = 3.6938 (11) Å] along [010].

(E)-N'-(4-Fluoro­benzyl­idene)-2-(3-methyl­phen­yl)acetohydrazide

In the title compound, C₁₆H₁₅FN₂O, the dihedral angles between the benzene rings are74.7(8), 74.1 (1), 74.2 (7) and 74.3 (5)° in the four independent mol­ecules in the asymmetric unit. In the crystal, N-H-O hydrogen bonds involving the hydrazide and acetyl groups, which form R₂²(18) ring motifs, link the mol­ecules into dimers, which form columns along [010].

2-(4-Bromo­phen­yl)-N-(3,4-di­fluoro­phen­yl)acetamide

In the title compound, C₁₄H₁₀BrF₂NO, the dihedral angle between the mean planes of the 4-bromo­phenyl and 3,4-di­fluoro­phenyl rings is 66.4 (1)°. These two planes are twisted by 40.0 (5) and 86.3 (2)°, respectively, from that of the acetamide group. In the crystal, N—H...O hydrogen bonds and weak C—H...O and C—H...F inter­actions form infinite chains along [100].

2-(4-Chloro­phen­yl)-N-(3,4-di­fluoro­phen­yl)acetamide

In the title compound, C₁₄H₁₀ClF₂NO, the dihedral angle between the mean planes of the 4-chloro­phenyl and 3,4-di­fluoro­phenyl rings is 65.2 (1)°. These two planes are twisted by 83.5 (5) and 38.9 (9)°, respectively, from that of the acetamide group. In the crystal, N—H...O hydrogen bonds form infinite chains along [100]. Weak C—H...O and C—H...F inter­actions are also observed and stack mol­ecules along the b axis.