The first example of the Pd-catalyzed addition of organoboron reagents to dinitriles, as an efficient means of preparing 2,5-diarylpyrroles and 2,6-diarylpyridines, has been discussed here. Furthermore, the highly selective carbopalladation of dinitriles with organoboron reagents to give long-chain ketonitriles has been developed as well. Based on the broad scope of substrates, excellent functional
The first cyclometallated compounds of some 2,6-diarylpyridines (2) and the relatedligand, 5,6,8,9-tetrahydrodibenz[c, h]acridine (3) were prepared and characterized as acetato-bridged palladium(II) dimers: [Pd(2 or 3)OAc]2. Inseparable isomers (syn,trans and syn,cis) were indicated by NMR, with the syn,trans isomer invariably predominating. With an unsymmetrical 2, both isomers reuslting from metallation
Pyridine-cored V-shaped π-conjugated oligomers: synthesis and optical properties
作者:Debabrata Jana、Binay K. Ghorai
DOI:10.1016/j.tet.2012.06.096
日期:2012.9
A new series of V-shaped pyridine-cored pi-conjugated oligomers are synthesized utilizing two-fold Heck/Suzuki coupling reactions. Optical properties of these compounds (lambda(max)=390-449 nm, phi(eta)=79-5%, in solutions) are discussed. They are shown to be thermally stable and soluble in common organic solvents. Stilbenoid oligomers exhibited much higher fluorescence quantum yields than tri- and tetra-phenylethylene substituted oligomers in solutions. (C) 2012 Elsevier Ltd. All rights reserved.
Synthesis of Asymmetrical 2,6-Diarylpyridines from Linear α,β,γ,δ-Unsaturated Ketones by Addition of Ammonium Formate Followed by Annulation
作者:Yejun Gao、Rener Chen、Yongmin Ma
DOI:10.1055/s-0037-1610725
日期:2019.10
established for the synthesis of asymmetrical 2,6-diarylpyridines by cyclization of α,β,γ,δ-unsaturated ketones with ammonium formate under air atmosphere. The reaction is metal-free and operationally convenient from readily available starting materials. Thirty-three examples have been presented, most of which show good yields. A simple and efficient method has been established for the synthesis of asymmetrical
4-bromoacetophenone in six steps is presented. The dications bind to poly dA.dT in the order 7 > 13 > 18 > 8 > 9; the order of binding to poly A.U is 7 > 13 > 8 > 9; 18 essentially does not bind to the RNA model. Only 7 inhibits topoisomerase II at millimolar concentrations. The dicationic compounds that were tested against Pneumonocystis carinii in the immuno-suppressed rat model show only modest activity