In 2019,Journal of the American Chemical Society included an article by Liu, Kanglei; Lalancette, Roger A.; Jakle, Frieder. Computed Properties of C6H6BrN. The article was titled 《Tuning the Structure and Electronic Properties of B-N Fused Dipyridylanthracene and Implications on the Self-Sensitized Reactivity with Singlet Oxygen》. The information in the text is summarized as follows:
We demonstrate that the modification of anthracene with B ← N Lewis pairs at their periphery serves as a highly effective tool to modify the electronic structure with important ramifications on the generation and reactivity toward singlet oxygen. A series of BN-fused dipyridylanthracenes with Me groups in different positions of the pyridyl ring have been prepared via directed electrophilic borylation. The steric and electronic effects of the substituents on the structural features and electronic properties of the isomeric borane-functionalized products have been investigated in detail, aided by exptl. tools and computational studies. We find that BDPA-2Me, with Me groups adjacent to the pyridyl N, has the longest B-N distance and shows overall less structural distortions, whereas BDPA-5Me with the Me group close to the anthracene backbone experiences severe distortions that are reflected in the buckling of the anthracene framework and dislocation of the boron atoms from the planes of the Ph rings they are attached to. The substitution pattern also has a dramatic effect on the self-sensitized reactivity of the acenes toward O2 and the thermal release of singlet oxygen from the resp. endoperoxides. Kinetic analyses reveal that BDPA-2Me rapidly reacts with O2, whereas BDPA-5Me is converted only very slowly to its endoperoxide. However, the latter serves as an effective singlet oxygen sensitizer, as demonstrated in the preferential formation of the endoperoxide of dimethylanthracene in a competition experiment These results demonstrate that even relatively small modifications in the substitution of the pyridyl ring of BN-fused dipyridylanthracenes change the steric and electronic structure, resulting in dramatically different reactivity patterns. Our findings provide important guidelines for the design of highly effective sensitizers for singlet oxygen on one hand and the realization of materials that readily form endoperoxides in a self-sensitized manner and then thermally release singlet oxygen on demand on the other hand. The experimental part of the paper was very detailed, including the reaction process of 2-Bromo-5-methylpyridine(cas: 3510-66-5Computed Properties of C6H6BrN)
2-Bromo-5-methylpyridine(cas: 3510-66-5) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Computed Properties of C6H6BrN