835-12-1Relevant academic research and scientific papers
Synthesis of 9-substituted fluorenols and heteroring-fused analogues by intramolecular ch functionalization
Kurimoto, Yuji,Mitsudo, Koichi,Suga, Seiji
supporting information, p. 378 - 381 (2021/03/15)
A method for the selective synthesis of 9-substituted fluorenols (FOLs) was developed by suppressing intermolecular cyclization and promoting intramolecular CH functionalization. This protocol was applied to the synthesis of heteroring-fused FOLs. Further, the obtained FOLs were converted to fulvenes by dehydration.
Chiral electron-rich PNP ligand with a phospholane motif: Structural features and application in asymmetric hydrogenation
Wang, Heng,Zhang, Yao,Yang, Tilong,Guo, Xiaochong,Gong, Quan,Wen, Jialin,Zhang, Xumu
supporting information, p. 8796 - 8801 (2020/11/13)
Despite the remarkable reactivity that was achieved by a series of transition-metal catalysts with a PNP type ligand, the electron-rich chiral PNP ligands have still been rarely reported because of the difficulties in synthesis and the nature of air-sensitivity. Herein, we report a novel chiral PNP ligand (Heng-PNP) with both a rigid backbone and a bulky tert-butyl group on the phospholane motif. We successfully obtained its divalent iron complex. The chiral environment of its Ir(III) complex was also discussed with quadrant analysis. This tridentate ligand was applied in iridium-catalyzed asymmetric hydrogenation of challenging diaryl ketones: up to 98% ee and 500 TON are achieved. Computational study showed that the twist of conjugate aryl group in the substrate (induced by the special chiral pocket of Ir/Heng-PNP complex) leads to the energy difference in the enantiodetermining step.
Synthesis of Substituted Naphthalenes by 1,4-Palladium Migration Involved Annulation with Internal Alkynes
Wei, Dong,Hu, Tian-Jiao,Feng, Chen-Guo,Lin, Guo-Qiang
supporting information, p. 743 - 748 (2018/07/25)
The palladium catalyzed annulation of 1-bromo-2-vinylbenzene derivatives with internal alkynes was realized for the efficient synthesis of substituted naphthalenes. A controllable aryl to vinylic 1,4-palladium migration process is the key for success.
The synthesis and electronic absorption spectra of 3-phenyl-3(4- pyrrolidino-2-substituted phenyl)-3H-naphtho[2,1-b]pyrans: Further exploration of the ortho substituent effect
Gabbutt, Christopher D.,Heron, B. Mark,Instone, Alicia C.
, p. 737 - 745 (2007/10/03)
Introduction of a substituent into a sterically demanding 2-position of a 3-(4-pyrrolidinophenyl) ring of a 3,3-diaryl-3H-naphtho[2,1-b]pyran results in the generation of an additional short wavelength absorption band leading to organic photochromes that
