3-Amino-5-(piperidin-1-yl)thio­phene-2,4-dicarbonitrile

In the title compound, C₁₁H₁₂N₄S, the thio­phene ring is roughly planar, with a maximum deviation of 0.012 (1) Å for the S atom, and makes a dihedral angle of 7.89 (8)° with the mean plane of the piperidine ring, which is in a chair conformation. The crystal packing is stabilized by pairs of centrosymmetric inter­molecular N—H...N hydrogen bonds, which results in the formation of a step-wise chain parallel to [10].

N-(Pyrrolidin-1-ylcarbothio­yl)benzamide

In the title compound, C₁₂H₁₄N₂OS, the pyrrolidine ring adopts an envelope conformation with the C atom at the 3-position as the flap and makes a dihedral angle of 65.80 (9)° with the benzene ring. In the crystal, N—H...O hydrogen bonds join c-glide related mol­ecules into chains extended along [001] that are further connected into (100) layers via C—H...O inter­actions.

2,2′-[2,5-Bis(hex­yloxy)-1,4-phenyl­ene]dithio­phene

The asymmetric unit of the title compound, C₂₆H₃₄O₂S₂, comprises one half-mol­ecule located on an inversion centre. The thio­phene groups are twisted relative to the benzene ring, making a dihedral angle of 5.30 (7)°, and the n-hexyl groups are in a fully extended conformation. In the crystal, there are short C—H...π contacts involving the thio­phene groups.

1,4-Dibromo-2,5-dibut­oxy­benzene

The asymmetric unit of the title compound, C₁₄H₂₀Br₂O₂, contains one half-mol­ecule located on an inversion centre. The mol­ecule is essentially planar, with a maximum deviation from the best plane of the non-H atoms of 0.054 (2) Å for the O atoms. The but­oxy group adopts a fully extended all-trans conformation. In the crystal, mol­ecules are connected via C—Br...O halogen bonds [Br...O = 3.2393 (19) Å] into a two-dimensional corrugated network in the bc plane.