Synthesis of Some Benzimidazole-substituted Benzotriazoles

2-Alkylsubstituted benzimidazoles (3a–h) were prepared from the acid-catalyzed reaction of 4-methyl-1,2-phenylenediamine with corresponding carboxylic acids. Addition of these benzimidazoles to N-chloromethylbenzotriazole in the presence of sodium amide under reflux conditions gave the novel benzimidazole-substituted benzotriazoles (5a–f). IR and 1HNMR spectroscopy and elemental analysis were used for the identification of these compounds.Keywords: Phenylenediamine, benzimidazole, benzotriazol

Kinetic H/D exchange study of Co(III) coordination compounds of diazines using NMR spectroscopy

The Co(III) diazines complexes having composition (NH3) 5CoPhtz)(ClO4), (1) (Phtz = phthalazine), (NH 3)5CoPydz)(ClO4)3 (2) (Pydz = pyradazine), (NH3)5Co(3-Me-Pydz)(ClO4) 3 (3) (3-Me-Pydz = 3-methyl pyradazine) and (NH3) 5Co(3-MePhtz)(ClO4)3 (4) (3-MePhtz = 3-methyl phthalazine), (NH3)5Co(ImH)(ClO4), (5) (ImH = imidazole), (NH3)5Co(NMeIm)(ClO4) 3 (6) (N-MeIm = N-methylimidazole) undergo OD--catalyzed H/D exchange at the ortho position of the coordinated site. Rate constants for H/D exchange of these complexes at 25°C or 60°C were obtained in alkaline D2O solution using NMR spectroscopy. Reaction rate for (NH3)5CoPhtz)(ClO4)3, (NH 3)5CoPydz)(ClO4)3, (NH 3)5Co(3-MePydz)(ClO4)3 and (NH3)5Co(3-MePhtz)(ClO4)3 at 25°C are faster compared to (NH3)5Co(ImH)(ClO 4)3, (NH3)5Co(N-MeIm)(ClO 4)3 (7). However (NH3) 5CoImCo(NH3)5Br5 complex does not H/D exchange at 60°C even in strong alkaline D2O solution

One-pot synthesis of tetrahydropyrimidines catalyzed by zeolite

A simple one-pot synthesis of various tetrahydro pyrimidines in the presence of NaY zeolite, as an efficient catalyst, is reported. The multicomponent reaction was carried out by a three-component coupling of 1,3-diketone, aldehyde and urea/thiourea in the presence of the catalyst to give 1(a-k). The catalyst could be reused several times. Further reaction of these pyrimidines with phosphorus oxychloride gave corresponding N-formylated compounds

SYNTHESIS OF SOME NOVEL AND BIOLOGICALLY ACTIVE SCHIFF BASES BEARING A 1,3,4-THIADIAZOLE MOIETY UNDER ACIDIC AND PTC CONDITIONS

The synthesis of some new Schiff bases bearing a 1,3,4-thiadiazole moiety, 3a-l, by reaction of 2-amino-5-mercapto-1,3,4-thiadiazole with aromatic aldehydes under acidic and phase transfer catalyst (PTC) conditions was studied. The structure of all the Schiff bases was characterized using FT-IR and NMR spectroscopy, and elemental analyses. The antibacterial activity of these compounds was investigated against Staphylococcus aureus (RTCC, 1885), and Escherichia col