3158-85-8Relevant articles and documents
Oxidative Synthesis of Quinazolinones under Metal-free Conditions
Feng, Jian-Bo,Wu, Xiao-Feng
, p. 794 - 798 (2017)
A metal-free procedure for the synthesis of quinazolinones under oxidative conditions has been developed. In the presence of DABCO and TBHP, the desired products can be obtained in moderate yields with 2-fluorobenzaldehydes and 2-aminopyridines as the substrates.
An Alternative Approach to the Hydrated Imidazoline Ring Expansion (HIRE) of Diarene-Fused [1.4]Oxazepines
Grintsevich, Sergey,Sapegin, Alexander,Reutskaya, Elena,Peintner, Stefan,Erdélyi, Máté,Krasavin, Mikhail
, p. 5664 - 5676 (2020/07/21)
A four-step approach to the “hydrated imidazoline ring expansion” (HIRE) is presented. In most cases, the ring expansion was the sole process. However, for the first time, an alternative course of the hydrated imidazoline evolution was discovered which gave N-aminoethyl derivatives. These can, in principle, be converted into the target HIRE products under sufficiently forcing conditions. The approach offers improved flexibility with respect to the peripheral substituents and is also applicable to the synthesis of eleven-membered lactams. We observed that the latter can exist in two stable isomeric forms due to lactam–amide bond isomerization. The latter finding further demonstrates the value of medium-sized rings as multiple-conformer probes for biological target interrogation.
Design of Conjugated Molecules Presenting Short-Wavelength Luminescence by Utilizing Heavier Atoms of the Same Element Group
Yamaguchi, Madoka,Tanaka, Kazuo,Chujo, Yoshiki
, p. 1342 - 1347 (2018/04/30)
The introduction of heavy atoms into conjugated molecules often induces a redshift in the emission spectra. Conversely, we report here a blueshifting effect in the absorption and emission bands of a conjugated organic dye by employing a heavier atom from the same element group. Boron complexes having oxygen- and sulfur-bridged structures in the ligand moiety were synthesized, and their optical properties were compared. Significant optical bands in the absorption and luminescence spectra of the sulfur-bridged complex were observed in a shorter wavelength region than those of the oxygen-bridged complex. Theoretical calculations suggest that replacement of the bridging atom by a heavier one should reduce molecular planarity because of the larger atom size. As a result, the degree of electronic conjugation decreases, and this is followed by a blueshift in the optical bands. Finally, a blue-emissive crystal is demonstrated.
