Ana M. Plutín

Alkylation of Benzoyl and Furoylthioureas as Polydentate Systems

Abstract A study of the behaviour towards alkylation of a series of benzoyl and furoylthioureas with 3,3-disubstitution has been carried out using NMR determinations. X-Ray data and semiempirical theoretical calculations demonstrated that the most stable conformation for these molecules is the so-called quasi-S. Also an explanation of the high selectivity towards the S-alkylation of these systems, based on the high contribution of the sulphur atom to the HOMO in acylthioureas is given for the title compounds. Steric factors are responsible for the difference between the percentages obtained for the S-alkylated product in 1-(4-methylbenzoyl)-3,3-diethylthiourea and 1-benzoyl-3,3-dibenzylthiourea.

Efficient Synthesis of 1-(4′-Methylbenzoyl)- 3,3-Diethylthiourea Under Microwave Irradiation Using Potassium Fluoride on Alumina

Abstract 1,1-diethylthiourea and 4-methylbenzoic acid were condensed to 1-(4′-methylbenzoyl)-3,3-diethylthiourea in open vessels under microwave irradiation using an unmodified domestic microwave oven. The synthesis was carried out in the presence of alumina impregnated with potassium fluoride and catalytic amounts of N,N-dimethylformamide. The yields are noticeably improved in comparison with classical methods.

Synthesis of 1-benzoyl-3-alkylthioureas by transamidation under microwave in dry media

Abstract 1-Benzoyl-3,3-diethylthiourea was transamidated with several amines to the corresponding 1-benzoyl-3-alkylthioureas in open vessels under microwave irradiation using a domestic oven. The syntheses were performed in solvent-free conditions on potassium fluoride impregnated alumina. Yields were dramatically improved in comparison with classical heating under the same conditions.

Probing the relationships between molecular conformation and intermolecular contacts in N,N-dibenzyl-N'-(furan-2-carbonyl)thiourea.

In the crystal structure of the title compound, C(20)H(18)N(2)O(2)S, molecules are linked by bifurcated C-H···O hydrogen-bond interactions, giving rise to chains whose links are composed of alternating centrosymmetrically disposed pairs of molecules and characterized by R(2)(2)(10) and R(2)(2)(20) hydrogen-bonding motifs. Also, N-H···S hydrogen bonds form infinite zigzag chains along the [010] direction, which exhibit the C(4) motif. Hirshfeld surface and fingerprint plots were used to explore the intermolecular interactions in the crystal structure. This analysis confirms the important role of C-H···O hydrogen bonds in the molecular conformation and in the crystal structure, providing a potentially useful tool for a full understanding of the intermolecular interactions in acylthiourea derivatives.

Synthesis, characterization, and crystal structure of Ni(II) and Cu(II) complexes with N-furoyl-N′,N′-diethylthiourea: antifungal activity

The complexes cis-bis(N-furoyl-N′,N′-diethylthioureato-k 2O,S)nickel(II) and cis-bis(N-furoyl-N′,N′-diethylthioureato-k 2O,S)copper(II) were prepared by the reaction of metal acetate with the corresponding acylthiourea derivative. The complexes were characterized by IR, 1H-NMR, 13C-NMR, and single-crystal X-ray diffraction. Both complexes show two furoylthiourea ligands bonded to metal to form a four-coordinate complex with square-planar geometry. The antifungal activity of the prepared complexes was studied against the phytopathogenic fungi Botrytis cinerea and Colletotrichum gloeosporioides, responsible for important plant diseases.

Tris(N-benzoyl-N′,N′-diphenyl­thio­ureato-κ2O,S)cobalt(III)

In the title compound, [Co(C20H15N2OS)3], the CoIII atom is coordinated by the S and O atoms of three N-benzoyl-N′,N′-diphenylthiourea ligands in a slightly distorted octahedral geometry. The O and S atoms are in cis positions, while the positions between the O and S atoms are trans.

cis-Bis(N-benzoyl-N',N'-dibenzyl-thio-ureato-κO,S)nickel(II).

In the title compound, [Ni(C22H19N2OS)2], the NiII atom is coordinated by the S and O atoms of two N-benzoyl-N′,N′-dibenzylthioureate ligands in a slightly distorted square-planar geometry. The two O atoms are cis, as are the two S atoms.

cis-Bis[N-(2-furoyl)-N',N'-diphenyl-thio-ureato-κO,S]nickel(II).

In the title compound, [Ni(C18H13N2O2S)2], the NiII atom is coordinated by the S and O atoms of two N-furoyl-N′,N′-diphenylthioureate ligands in a slightly distorted square-planar coordination geometry. The two O and two S atoms are cis to each other.

Tris[N-(2-furoyl)-N,N′-diphenyl­thio­ureato-κ2O,S]cobalt(III)

In the title compound, [Co(C18H13N2O2S)3], the CoIII atom is coordinated by the S and O atoms of three N-furoyl-N′,N′-diphenylthiourea ligands in a slightly distorted octahedral geometry. The three O atoms are arranged fac, as are the three S atoms.

Spectroscopic characterization and crystal structure of cis-Bis(N-(2-benzoyl)-N′,N′-diphenylthioureato-k2O,S)nickel(II)

The title compound [Ni(C20H15N2OS)2] is prepared by the reaction of metal acetate with the corresponding acylthiourea derivative. The complex is characterized by elemental analysis, IR, 1H and 13C NMR, and its structure is determined by single crystal X-ray diffraction. The Ni(II) ion is coordinated by the S and O atoms of two N-benzoyl-N′,N′-diphenylthiourea ligands in a slightly distorted square-planar coordination geometry. The two O and two S atoms are mutually cis to each other. The substance crystallizes triclinic (P-1 space group) with cell dimensions a = 10.7262(9) Å, b = 12.938(3) Å, c = 14.2085(12) Å, α = 74.650(4)°, β = 78.398(4)°, γ = 68.200(5)°, and two formula units in the unit cell. The structure is very close to the related N-(2-furoyl) Ni complex reported previously.