Synthesis of Tris Pyrazolylborate Lab Report Example | Topics and Well Written Essays - 1000 words

Synthesis of Tris Pyrazolylborate - Lab Report ExampleTrispyrazolylborate (Tp) is an organic anionic tetradentate or tripodal ligand that has the chemical formula HB (C3N2H3)3. Trispyrazolylborate specifically refers to the derivatives substituted on the pyrazolyl rings. In the resonance structures of this compound, the nitrogen centers that be not bonded to vitamin B complex are basic (Topaloglu-Sozuer et al., 2005). These centers bond to three adjacent sites of a metal such that the simple adducts take on C3v symmetry. The bonding mode is similar to that of cyclopentadienyl ligands though the ligand field stabilization energy of Tp- is weaker as indicated by the point that Fe (Tp)2 is a spin crossover complex while ferrocene is low spin (Yong Heng, Aoki, & Feng Ying, 2004). The Tp ligands are disposed(p) in the laboratory by reacting pyrazole with atomic number 19 borohydride according to the equationKBH4 + 3C3H3N2H K HB (C3N2H3)3 +3H2The intermediate compounds include the mo nopyrazolylborate (H3B (C3N2H2)2- and the bispyrazolylborate (H2B(C3N2H2)2-. The potassium Trispyrazolylborate is a colorless solid that is soluble in polar solvents and has a melting point of 188-1890C (Maldonado, & Vahrenkamp, 2006).When 3-substituted pyrazoles are condensed with borohydride, the corresponding substituent Trispyrazolylborate derivatives are formed. The substituent formed pushes boron the less hindered nitrogen center and hence 3-phenylpyrazole gives HB (C3N2H2Ph) 3- whereas the phenyl substituents project away(predicate) from the metal.