Results 91 to 100 of about 11,071 (289)

Control over Structure Formation of Small Molecular Weight Thiophenes in Vacuum Deposited Films

Advanced Materials Interfaces
Recent structural studies of small‐molecular‐weight thiophenes are surveyed, with particular focus on naphthyl‐end‐capped derivatives and comparison to alkyl‐capped and unsubstituted analogues.
Matti Knaapila, Mathias K. Huss‐Hansen, Jakob Kjelstrup‐Hansen   +2 more
doaj   +1 more source

Identification of Larvicidal Constituents of the  Essential Oil of Echinops grijsii Roots against the  Three Species of Mosquitoes

Molecules, 2017
The screening of Chinese medicinal herbs for insecticidal principles showed that the essential oil of Echinops grijsii Hance roots possessed significant larvicidal activity against mosquitoes.
Mei Ping Zhao, Qi Zhi Liu, Qiyong Liu, Zhi Long Liu   +3 more
doaj   +1 more source

Catalyst‐Controlled Regiodivergent C−H Alkynylation of Thiophenes**

, 2020
Alkynes are highly attractive motifs in organic synthesis due to their presence in natural products and bioactive molecules as well as their versatility in a plethora of subsequent transformations. A common procedure to insert alkynes into hetero(arenes),
Manuel van Gemmeren, Arup, Mondal, Arup Mondal, Manuel, van Gemmeren   +3 more
core   +1 more source

Lewis Acid Catalysis in the Oxidative Cycloaddition of Thiophenes [PDF]

, 1997
Thiophenes 1 were treated with m-chloroperbenzoic acid (m-CPBA) under BF3·Et2O catalysis to afford thiophene S-monoxides. These could be reacted in situ as intermediary species with a number of dienophiles to provide arenes (with alkynes as dienophiles ...
Mataka, Shuntaro, Tashiro, Masashi, Li, Yuanqiang, Sawada, Tsuyoshi, Thiemann, Thies   +4 more
core   +1 more source

Atroposelective Access to π‐Conjugated 1,2‐Azaborepines Enabled by Palladium‐Catalyzed Cyclization of N‐Heterobiaryls with Alkynylboronates

Advanced Science, EarlyView.
We report a palladium‐catalyzed atroposelective cyclization of N‐heterobiaryl triflates with alkynyl boronates to access seven‐membered 1,2‐BN‐bridged biaryls with high yields and excellent enantioselectivity via a cascade DyKAT, cis‐carbopalladation, and 1,2‐migration, which expands the toolbox for axially chiral π‐conjugated boron compounds and opens
Fengya He, Zhen Wang, Haoyu Guo, Shuguang Chen, Xu Zhang, Yongjia Shang, Hui Wang   +6 more
wiley   +1 more source

Photosensitizing thiophenes from the Tageteae

, 1981
Two separate aspects involving the thiophenes of the Tageteae (Asteraceae) were investigated. The first concerned the distribution of four thiophenes in Tagetes patula L. which were examined by high pressure liquid chromatography (HPLC).
Downum, Kelsey
core  

Asymmetric Hydrogenation of Thiophenes and Benzothiophenes

, 2016
An efficient and highly asymmetric ruthenium-N-heterocyclic carbene-catalyzed hydrogenation of substituted thiophenes and benzothiophenes is described, providing a new strategy for the formation of valuable enantiomerically pure tetrahydrothiophenes and ...
Daniel Paul (1880098), Slawomir Urban (2042758), Bernhard Beiring (2042761), Frank Glorius (1555042), Nuria Ortega (1973692)   +4 more
core   +1 more source

Concentration‐Driven Li+ Solvation Engineering with TDMAP‐Based Porphyrin Additives for Dendrite‐Free Li Metal Batteries

Advanced Science, EarlyView.
The electrolyte engineering of introducing tetrakis(4‐N, N‐dimethylaminophenyl)porphyrin (TDMAP) is designed to modulate Li+ solvation structure and solid electrolyte interphase, where the interaction with PF₆− anions is altered (Li+–NMe2–PF₆−). Consequently, the cells with optimal additive concentration achieve high Coulombic efficiency (∼99%), and ...
Pooria Afzali, Jian Wang, Sergio Rodriguez, Jin‐Hyun Chang, Luca Magagnin, Maximilian Fichtner   +5 more
wiley   +1 more source

Identifying the missing link in catalyst transfer polymerization

Nature Communications, 2018
The mechanism for nickel-catalyzed catalyst transfer polycondensation of thiophenes to polythiophenes. Here the authors show experimental and computational evidence of structurally characterized square planar η 2-Ni(0)–thiophene species and their ...
Weiying He, Brian O. Patrick, Pierre Kennepohl   +2 more
doaj   +1 more source

Componentes voláteis do café torrado. Parte I: compostos heterocíclicos Volatile components in roasted coffee. Part I: heterocyclic compounds

Química Nova, 1999
A review of heterocyclic compounds in roasted coffee is presented. The contents, precursors and sensorial properties of furans, pyrroles, oxazoles, thiazoles, thiophenes, pyrazines and pyridines are discussed.
Carlos Alberto Bastos De Maria, Ricardo Felipe Alves Moreira, Luiz Carlos Trugo   +2 more
doaj   +1 more source