Spectroscopic Elucidation of Some Complexes of Vanillin Semicarbazone

3-Phenyl-4-methoxybenzaldehyde undergoes condensation with semicarbazide hydrochloride to form a Schiff-base i.e. 3-phenyl-4-methoxybenzaldehyde semicarbazone (abbreviated as MBS). It undergoes complexation with Vanadium(II), Manganese(II), and Copper(II). The comparison of FTIR-spectra of complexes with that of free ligand helps ascertain the coordination points of ligand through the nitrogen of –CH=N– group and oxygen of group. The axial ligands have been varied by chloride, acetate and nitrate ions. The UV/Visible and ESR spectra of complexes predicts their tetragonally distorted octahedral (D4h) symmetry. The tetragonal distortion parameter (Dt) is observed maximum for chloride while it is minimum for nitrate along z-axis. Both vanillin and semicarbazide are established biologically active compounds and hence their biological activities may be enhanced by their complexation and than a versatile field may be developed for further exploration.

Synthesis of 5-Nitro-1,2,4-Triazol-3-One Via: Conventional Heating, Microwave and Ultrasonication

In this laboratory experiment 2,4-dihydro-3H-1,2,5-Triazol-3-one(TO) was synthesized using mixture of semicarbazide hydrochloride(SC.HCl) and formic acid in 1:3 mole ratio. TO was further nitrated using 70% nitric acid (HNO3) to produce2,4-dihydro-3H-5-nitro-1,2,5-triazol-3-one(NTO). For the nitration reaction three techniques were employed: conventional heating, microwave assisted and ultrasound assisted reaction. It was found that the extent of gases generation during the reaction was reduced when microwave and ultrasound was employed as compared to the conventional heating method. The time taken for the completion of the reaction was only 15 min when microwave was used.

A New Efficient Route to 2-Alkylsemicarbazides

Synthesis of hardly available 2-alkylsemicarbazides and their hydrochlorides from semicarbazide hydrochloride has been developed. This general and efficient protocol is based on preparation of acetone semicarbazone, its N2-alkylation in the presence of sodium hydride, and hydrolysis under mild conditions.

Green Cyclocondensation of β-Ethylthio-β-indolyl-α, β-unsaturated Ketones with Semicarbazide Hydrochloride as Hydrazine Equivalent in Water: Aqueous Synthesis of 3-Pyrazolyl Indoles

A green and efficient cyclocondensation reaction of β-ethylthio-β-indolyl-α, β-unsaturated ketones with semicarbazide hydrochloride as hydrazine equivalent to prepare 3-pyrazolyl indoles had been developed in the presence of 3 equiv. of PEG-400 in reflux water. This procedure did not require toxic hydrazine and product purification, eliminating the use of toxic liquid chemicals.