Although several synthesized icosahedral carborane fused 2D π-ring systems are known, and even considerable conjugation has been noted between them in some cases, the phenomenon itself is not fully understood....

A set of o-carborane appended π-conjugated fluorophores and their light-emitting properties in solid state are reported. The aggregation-induced emission enhancement (AIEE) exhibited for one of the fluorenyl derivatives paved the...

The synthesis of novel 3,4-dihydropyrimidin-2(1H)-one-phosphonates was elaborated by the microwave (MW)-assisted three-component Biginelli reaction of β-ketophosphonates, aromatic or aliphatic aldehydes and urea derivatives. The condensation was optimized on a selected model reaction in respect of the reaction parameters, such as the heating method, the type of the catalyst and solvent, the temperature, the reaction time and the molar ratio of the starting materials. The fast and solvent-free MW-assisted procedure was then extended for the preparation of further new 3,4-dihydropyrimidin-2(1H)-one-phosphonate derivatives starting from different aromatic aldehydes, β-ketophosphonates and urea derivatives to prove the wide scope of the process. As a novel by-product of the Biginelli-type synthesis of 3,4-dihydropyrimidin-2(1H)-one-phosphonates, the 5-diethoxyphosphoryl-4-phenyl-6-styryl-3,4-dihydropyrimidin-2(1H)-one was also isolated and characterized. Our MW-assisted method made also possible the condensation of aliphatic aldehydes, diethyl (2-oxopropyl)phosphonate and urea, which reaction was previously reported to be impossible in the literature.

The reaction mechanism of the phosphane catalyzed chemoselective 1,2-reduction of ynones using pinacolborane has been explored computationally. Numerous plausible reaction routes were investigated, and calculations based on density function theory showed that the hydride transfer to the vinylphosphonium cations in the catalytic cycle leads to dead-ends. The in situ formed dioxaborolane acts as the hydride donor and the reaction proceeds on a parallel path. Alternative mechanisms have also been examined alongside the crucial role of theoretical levels, moreover, the effect of a solvent was taken into consideration by applying the implicit polarizable continuum model.