M. Sukeri M. Yusof

N-(4-Chloro-butano-yl)-N'-phenyl-thio-urea.

The asymmetric unit of the title compound, C11H13ClN2OS, contains two independent molecules. Both molecules maintain a trans–cis configuration with respect to the position of the carbonyl group and the benzene ring against the thione group across the C—N bonds. The molecules are stabilized by intramolecular N—H⋯O hydrogen bonds. In the crystal, the molecules are linked by intermolecular N—H⋯S, N—H⋯O and C—H⋯S hydrogen bonds into chains along the c axis. C—H⋯π interactions further stabilize the crystal structure.

1,2-Bis[N′-(2,2-dimethyl­propionyl)thio­ureido]cyclo­hexa­ne

In the title compound, C18H32N4O2S2, the dihedral angle between the two thiourea groups is 78.55 (7)°. The molecular conformation is stabilized by intramolecular N—H⋯O hydrogen bonds and the crystal structure is stabilized by intermolecular N—H⋯O and C—H⋯O hydrogen bonds, forming centrosymmetric dimers.

The Effect of Concentration of Lawsonia inermis as a Corrosion Inhibitor for Aluminum Alloy in Seawater

Lawsonia inermis also known as henna was studied as a corrosion inhibitor for aluminum alloy in seawater. The inhibitor has been characterized by optical study via Fourier transform infrared spectroscopy (FTIR). The FTIR proves the existence of hydroxyl and carbonyl functional groups in Lawsonia inermis. Aluminum alloy 5083 immersed in seawater in the absence and presence of Lawsonia inermis was tested using electrochemistry method, namely, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP). EIS and PP measurements suggest that the addition of Lawsonia inermis has caused the adsorption of inhibitor on the aluminum surface. The adsorption behavior of the inhibitor follow Langmuir adsorption model where the value of free energy of adsorption, , is less than 40 kJ/mol indicates that it is a physical adsorption. Finally, it was inferred that Lawsonia inermis has a real potential to act as a corrosion inhibitor for aluminum alloy in seawater.

N-(2,2-Dimethyl-propano-yl)-N'-(2-meth-oxy-phen-yl)thio-urea.

In the title compound, C13H18N2O2S, the carbonylthiourea fragment is nearly planar with an r.m.s. deviation of 0.0096 Å. The dihedral angle between carbonylthiourea group and the benzene ring is 19.16 (16)°. There are two intramolecular N—H⋯O hydrogen bonds, which lead to two pseudo-six-membered rings. Weak intramolecular C—H⋯S hydrogen bonding also occurs.

Bis{N-[methoxy(4-methylbenzamido)methyl]-2,4-dimethylanilinido-κ2N,O}copper(II)

In the centrosymmetric mononuclear title complex, [Cu(C18H20N2O2)2], the CuII atom is four-coordinated in a trans-CuN2O2 square-planar geometry with the N—Cu—O chelate angle being 89.97 (11)°. The dihedral angles made by the planes defined by the aromatic ring carbons of the 4-methylbenzene and 2,4-dimethylbenzene fragments with the plane defined by the chelate ring are 13.43 (15) and 82.69 (13)° respectively. The angle between the planes defined by the aromatic carbons of the two rings is 89.40 (16)°. A a weak intramolecular C—H⋯N hydrogen bond occurs.

1-(4-Chloro­benzo­yl)-3-(3-methyl­pyridin-2-yl)thio­urea

The molecule of the title compound, C14H12ClN3OS, consists of three approximately planar fragments: the central thiourea group, the chlorophenyl group and the picolyl (3-methylpyridin-2-yl) group with a maximum of 0.035 (2)° for an N atom from the mean square plane of the central thiourea group. The central fragment forms dihedral angles of 33.30 (8) and 76.78 (8)° with the chlorophenyl and picolyl groups, respectively. With respect to the thiourea C—N bonds, the 4-chlorobenzoyl group is positioned trans to the thiono S atoms, whereas the picolyl group lies in a cis position to it. The molecular conformation is stabilized by an intramolecular N—H⋯O hydrogen bond. In the crystal, molecules are linked by intermolecular C—H⋯N hydrogen bonds, forming chains along the a axis.

N-(4-Methylbenzoyl)-N′-(4-methylphenyl)thiourea

The title compound, C16H16N2OS, adopts a trans–cis configuration of the 4-methylbenzoyl and 4-methylphenyl groups, with respect to the thiono S atom across the thiourea C—N bonds. The dihedral angle between the two groups is 10.36 (8)°. The structure is stabilized by intermolecular hydrogen bonds which form dimers. There are also intramolecular hydrogen bonds.