Synthesis and Characterization of some Thiazolidinone Derivatives Possessing Benzimidazole Nucleus

Synthesis of new thiazolidinone derivatives possessing benzimidazole nucleus by condensation reaction of various substituted mercapto acids in presence of anhydrous ZnCl2. In our present study we have also synthesized Schiff bases of benzimidazole derivatives. All synthesized compounds were characterized by IR, 1H NMR and Mass spectroscopy.

The solid-state structure of bis(pentafluorophenyl)zinc

Using the published method of Wiedenbruch, bis(pentafluorophenyl)zinc, 1, was prepared from anhydrous ZnCl2 and 2 equiv. of LiC6F5 in diethyl ether. Base-free 1 was obtained in 60-65% yield by repeated distillation of the initially formed bis(diethyl) ether adduct of 1. The X-ray quality crystals of 1 were obtained from benzene solution. The molecular structure of 1 revealed a near linear geometry for the two-coordinate zinc center (C(1)-Zn-C(7) = 172.6(2)°), typical of monomeric ZnR2 derivatives. In the crystal structure, stacking interactions between C6F5 rings on adjacent molecules is a dominant motif, with ring centroid to ring centroid distances of 3.503 and 3.563 Å observed. A weak intermolecular C-F ...Zn interaction between F(2) and an adjacent zinc center, as judged by the close contact of 2.849(2) Å, also appears to be an important aspect of the crystal structure. Compound 1 is an effective but nonselective C6F5 transfer agent to BCl3; 1: monoclinic, space group P21/n, a = 11.902(2) Å, b = 7.732(2) Å, c = 13.735(2) Å, β = 110.58(1)°, V = 1183.4(4) Å3, Z = 4, R = 0.048, Rw = 0.069.Key words: organozinc complex, pentafluorophenyl transfer agent.