97442-87-0Relevant academic research and scientific papers
Iron-Catalyzed Vinylzincation of Terminal Alkynes
Huang, Qiang,Su, Yu-Xuan,Sun, Wei,Hu, Meng-Yang,Wang, Wei-Na,Zhu, Shou-Fei
supporting information, p. 515 - 526 (2022/01/08)
Organozinc reagents are among the most commonly used organometallic reagents in modern synthetic chemistry, and multifunctionalized organozinc reagents can be synthesized from structurally simple, readily available ones by means of alkyne carbozincation. However, this method suffers from poor tolerance for terminal alkynes, and transformation of the newly introduced organic groups is difficult, which limits its applications. Herein, we report a method for vinylzincation of terminal alkynes catalyzed by newly developed iron catalysts bearing 1,10-phenanthroline-imine ligands. This method provides efficient access to novel organozinc reagents with a diverse array of structures and functional groups from readily available vinylzinc reagents and terminal alkynes. The method features excellent functional group tolerance (tolerated functional groups include amino, amide, cyano, ester, hydroxyl, sulfonyl, acetal, phosphono, pyridyl), a good substrate scope (suitable terminal alkynes include aryl, alkenyl, and alkyl acetylenes bearing various functional groups), and high chemoselectivity, regioselectivity, and stereoselectivity. The method could significantly improve the synthetic efficiency of various important bioactive molecules, including vitamin A. Mechanistic studies indicate that the new iron-1,10-phenanthroline-imine catalysts developed in this study have an extremely crowded reaction pocket, which promotes efficient transfer of the vinyl group to the alkynes, disfavors substitution reactions between the zinc reagent and the terminal C–H bond of the alkynes, and prevents the further reactions of the products. Our findings show that iron catalysts can be superior to other metal catalysts in terms of activity, chemoselectivity, regioselectivity, and stereoselectivity when suitable ligands are used.
Optimized trade-offs between triplet emission and transparency in Pt(II) acetylides through phenylsulfonyl units for achieving good optical power limiting performance
An, Miao,Yan, Xiaogang,Tian, Zhuanzhuan,Zhao, Jiang,Liu, Boao,Dang, Feifan,Yang, Xiaolong,Wu, Yong,Zhou, Guijiang,Ren, Yixia,Gao, Loujun
, p. 5626 - 5633 (2016/07/06)
Three Pt(ii) acetylides have been prepared by coupling trans-[PtCl2(PBu3)2] to ethynyl aromatic ligands with electron-withdrawing phenylsulfonyl units in high yields (>85%). The investigation of their photophysical behavior has shown that the unique conjugation-breaking configuration of the -SO2- linker in the phenylsulfonyl units can afford a very short cut-off wavelength (λcut-off) of P) of the prepared Pt(ii) acetylides can be effectively enhanced from 0.52% to 15.92% through increasing the number of fluorine substituents on the phenylsulfonyl units in the organic ligands. Benefiting from their enhanced ΦP, the phenylsulfonyl-based Pt(ii) acetylides can exhibit comparable or even better optical power limiting (OPL) performance against 532 nm lasers than the state-of-the-art OPL material C60, indicating their great potential in the field of laser protection. All of these results have provided a new strategy to achieve consistency between high OPL ability and good transparency for OPL materials, representing a valuable attempt for coping with key problems in the field of nonlinear optics.
Therapeutic alcohols
-
, (2008/06/13)
Compounds of formula I STR1 wherein X, A, B, R1 and R2 have the meanings given in the specification, and pharmaceutically acceptable salts and pharmaceutically acceptable in vivo hydrolysable ester thereof, processes for preparing the compounds and pharmaceutical compositions comprising them. The compounds are useful as potassium channel openers and as therapeutic agents in the treatment of urinary incontinence.
