The formation of keto-enamine based crystalline, porous polymers in water is investigated for the first time. Facile access to the Schiff base reaction in water has been exploited to synthesize stable porous structures using the principles of Dynamic Covalent Chemistry (DCC). Most credibly, the water-based Covalent Organic Frameworks (COFs) possess chemical as well as physical properties such a...

The role of NMR in the study of compounds of biological importance is widely recognized and appreciated. There can be few categories of such substances, however, to which NMR has made such substantive contributions as it has to the understanding of the chlorophylls and the corrins. The chlorophylls are indispensible agents in the conversion of the energy of light to chemical oxidizing and reduc...

The title compound, C(16)H(13)FN(2)OS, has undergone enol-to-keto tautomerism during the crystallization process. The 1H-pyrazole-5-one ring [maximum deviation = 0.0198 (11) Å] is inclined at angles of 33.10 (5) and 79.57 (5)° with respect to the fluoro-phenyl [maximum deviation = 0.0090 (12) Å] and phenyl-thiol [maximum deviation = 0.0229 (3) Å] rings attached to it. In the crystal, neighbouri...

The effect of Ni(II), Cu(II) and Zn(II) association on the diketo/keto-enol tautomerism of thymine has been investigated through the use of B3LYP density functional theory calculations. Final energies were obtained at the B3LYP/6-311+G(2df,2p)//B3LYP/6-311+G(d,p) level of theory. Ni(II) and Cu(II) lead to an oxidation of thymine which for Zn(ii) is only partial and catalyze the tautomerization ...