53148-57-5Relevant academic research and scientific papers
B-N coordinated triaryl pyrazole: Effect of dimerization, and optical and NLO properties
Mukundam, Vanga,Sa, Shreenibasa,Kumari, Anupa,Das, Ritwick,Venkatasubbaiah, Krishnan
, p. 12725 - 12737 (2019)
A series of triaryl pyrazole B ← N coordinate dimers with different π-conjugated (spacer) bridges (compound 4 (no spacer); compound 7 (2,5-bis(hexyloxy)benzene); compound 8 (9,9-dihexyl-9H-fluorene); compound 9 (9-hexyl-9H-carbazole); compound 10 (thiophene); compound 11 (2,2′-bithiophene)) has been synthesized from simple triaryl pyrazoles. Three different synthetic protocols were applied to synthesize the desired B ← N coordinate pyrazole dimers. All the B ← N coordinate pyrazole dimers exhibit absorption maxima between 337 and 399 nm with good molar absorption coefficients (12 000 to 22 100 M-1 cm-1 in CH2Cl2). They are highly emissive in the solution state with quantum yields of up to 0.94. Due to a substantial change in the excited state dipole moment, B ← N coordinate pyrazole dimers exhibit versatile and appreciably large nonlinear optical (NLO) properties. The dimer symmetry and the presence of donor or acceptor moieties affect the two-photon-absorption (TPA) cross-section substantially. In addition, the investigation reveals that the dimer π-conjugation length in all dimer variants has a remarkable impact on the NLO characteristics.
ONE-ELECTRON OXIDATION OF 1,3,5-TRIARYL-2-PYRAZOLINES BY ANTIMONY PENTACHLORIDE
Morkovnik, A. S.,Okhlobystin, O. Yu.
, p. 461 - 464 (2007/10/02)
Upon reaction of 1,3,5-triphenyl- and 1,3,5-triphenyl-5-methyl-2-pyrazolines with antimony pentachloride in acetonitrile they undergo oxidation to cation radicals, which subsequently undergo rapid dimerization at the para positions of the N-phenyl groups.
