Synthesis and antifungal activities of natural and synthetic biflavonoids
摘要:
The synthesis of some natural and synthetic biflavonoids was performed in good overall yields starting from readily available materials via high yielding aldol and Ullmann condensations. Some of these compounds, especially bichalcones, display an interesting activity against fungi, higher than that of the corresponding monomers. (C) 2011 Elsevier Ltd. All rights reserved.
Guest-Encapsulation Properties of a Self-Assembled Capsule by Dynamic Boronic Ester Bonds
作者:Naoki Nishimura、Kenji Yoza、Kenji Kobayashi
DOI:10.1021/ja9084918
日期:2010.1.20
selective recognition event, wherein the guest substituents are oriented to both aromatic cavity ends of 3a, as confirmed by a (1)H NMR study and X-ray crystallographic analysis. Capsule 3a showed a significant solvent effect on guest encapsulation. The association constant (K(a)) of 3a with guests in C(6)D(6) was much greater than that in CDCl(3) (450-48,000-fold). The encapsulation of guests within
Reductive Homocoupling of Organohalides Using Nickel(II) Chloride and Samarium Metal
作者:Yongjun Liu、Shuhuan Xiao、Yan Qi、Feng Du
DOI:10.1002/asia.201601712
日期:2017.3.16
(benzyl, aryl, heterocyclic, alkenyl and alkyl halides), α‐haloacetophenones, and phenyl organosulfonates were tolerated, and the reaction afforded coupling products with high efficiency. Excellent chemoselectivity was exhibited between halides and other groups, such as −COOH, −NO2, halogen, heterocyclic ring, ester, and ketone groups. The stereoselectivity suggested that the reactionmechanism might
Replacing Conventional Carbon Nucleophiles with Electrophiles: Nickel-Catalyzed Reductive Alkylation of Aryl Bromides and Chlorides
作者:Daniel A. Everson、Brittany A. Jones、Daniel J. Weix
DOI:10.1021/ja301769r
日期:2012.4.11
general method is presented for the synthesis of alkylated arenes by the chemoselective combination of two electrophilic carbons. Under the optimized conditions, a variety of aryl and vinyl bromides are reductively coupled with alkyl bromides in high yields. Under similar conditions, activated aryl chlorides can also be coupled with bromoalkanes. The protocols are highly functional-group tolerant (−OH,
Recyclable and reusable Pd(OAc)<sub>2</sub>/PPh<sub>3</sub>/PEG-2000 system for homocoupling reaction of arylboronic acids under air without base
作者:Jianhui Xia、Mingzhu Cheng、Qiurong Chen、Mingzhong Cai
DOI:10.1002/aoc.3254
日期:2015.2
A stable and efficient Pd(OAc)2/PPh3/PEG‐2000 catalytic system for homocoupling of arylboronicacids has been developed. In the presence of Pd(OAc)2 and PPh3, the homocouplingreaction of arylboronicacids was carried out smoothly in PEG‐2000 at 70 °C underairwithoutbase to afford a variety of symmetric biaryls in good to excellent yields. The isolation of the products was readily performed by extraction
Phosphine ligand triggered oxidative decarbonylative homocoupling of aromatic aldehydes: selectively generating biaryls and diarylketones
作者:Luo Yang、Tieqiang Zeng、Qi Shuai、Xiangyu Guo、Chao-Jun Li
DOI:10.1039/c0cc04921b
日期:——
A novel rhodium-catalyzed oxidative decarbonylative homocoupling of aromatic aldehydes to generate biaryls and diarylketones selectively and efficiently, triggered by the choice of different phosphine ligands.