1-[(6-Chloro-3-pyrid­yl)meth­yl]-5-eth­oxy-8-nitro-1,2,3,5,6,7-hexa­hydro­imidazo[1,2-a]pyridine

In the title compound, C15H19ClN4O3, an active agrochemical possessing insecticidal activity, the dihedral angle between the mean planes passing through the pyridine ring and the five-membered ring is 87.3 (2)°. The fused pyridine ring adopts a twisted sofa conformation. The mol­ecular structure features close intra­molecular C—H⋯N and C—H⋯O hydrogen bonding

1-[(1,3-Dithio­lan-2-yl)meth­yl]-6-methyl-8-nitro-1,2,3,5,6,7-hexa­hydro­imidazo[1,2-c]pyrimidine

In the title compound, C11H18N4O2S2, the dithiol­ane ring displays an envelope conformation, the tetra­hydro­pyrimidine ring has a conformation that is between half-chair and screw-boat, and the imidazole ring is essentially planar (r.m.s. deviation = 0.0017 Å). No significant directional inter­molecular inter­actions are present in the structure

(E)-1-(2,2-Dimeth­oxy­eth­yl)-2-(nitro­methyl­idene)imidazolidine

In the title compound, C8H15N3O4, the 2-(nitro­methyl­ene)imidazolidine fragment is close to being planar (r.m.s. deviation = 0.027 Å), which may be correlated with delocalization of the electrons and the effect of the strongly electron-withdrawing NO2 group. An intra­molecular N—H⋯O link generates an S(6) ring. The same H atom also forms a weak inter­molecular N—H⋯O hydrogen bond, which results in C(7) chains propagating in [010]

1-[(1,3-Dithio­lan-2-yl)meth­yl]-8-nitro-6-propyl-1,2,3,5,6,7-hexa­hydro­imidazo[1,2-c]pyrimidine

In the title compound, C13H22N4O2S2, the six-membered ring displays a half-chair conformation. The olefin amine unit is close to being coplanar with the imidazolidine ring (r.m.s. deviation = 0.059 Å). The dithiol­ane ring adopts a twisted conformation. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions

1-(2,2-Dimethoxyethyl)-8-nitro-1,2,3,5,6,7-hexahydroimidazo[1,2-a]pyridin-5-ol

In the title compound, C11H19N3O5, the six-membered ring displays a half-chair conformation and the imidazolidine ring is essentially planar (r.m.s. deviation = 0.088 Å). An intermolecular hydrogen bond between the hydroxy O atom and a nitro O atom stabilizes the crystal packing

Fabrication of a Heterobinuclear Redox Cycle to Enhance the Photocatalytic Activity of BiOCl

La3+ and Ni2+-doped BiOCl were prepared by sol–gel method and characterized by physicochemical and spectroscopic techniques. Their photocatalytic performances were investigated by the degradation of gentian violet under visible light. The results indicated that the co-doping of Ni and La significantly enhanced the photocatalytic performance of BiOCl. The photodegradation efficiency of LaNiBiOCl reached 95.5% in 105 min, which was 1.5 times that of BiOCl. This significant enhancement in photocatalytic activity was mainly attributed to the effective capture and transfer of photogenerated electrons between heterobinuclear La and Ni redox cycle, which benefited the photodegradation of active h+ and the formation of active •O2−. Furthermore, the photodegradation activity did not show an obvious drop after five recycles, indicating that LaNiBiOCl was a promising semiconductor photocatalyst for the degradation of gentian violet