Search results for "Lithium"

Über die anionische polymerisation von acrolein. Polymere acroleine. 34. Mitt.1

1967

Acrolein wurde mit Lithium-, Natrium- oder Kaliumcyanid in Tetrahydrofuran bzw.in Toluol polymerisiert. Die Abhangigkeit der Polymerisationsgeschwindigkeit und der Struktur der Polymeren von Reaktionsmedium, Temperatur und Gegenion wurde untersucht. Unterhalb -10°C polymerisiert Acrolein mit Natriumcyanid nur uber die CO. Doppelbindung. Es entstehen hochmolekulare, losliche Poly-3,4-acroleine. Oberhalb -10°C wird dagegen auch Polymerisation uber die Vinylgruppe beobachtet. Die Kurve fur die Abhangigkeit der Polymerisationsgeschwindigkeit von der Reaktionstemperatur durchlauft Extremwerte. Es wird ein Mechanismus aufgestellt, der die jeweilige Struktur des Polymeren als Ergebnis von Gleichge…

Addition of organolithium reagents to cinnamic acids

1999

Abstract Reaction of tert -butyllithium with p - and m -substituted cinnamic acids at low temperature affords mixtures of 1,4- and 1,3-addition products, whose composition depend on the nature of the substituents. Electron-donating and electron-withdrawing groups favour 1,4- and 1,3-additions, respectively. Linear correlations are obtained with electronic effect and with radical substituent constants.

A sigma-donor with a planar six-pi-electron B2N2C2 framework: anionic N-heterocyclic carbene or heterocyclic terphenyl anion?

2006

Formation of meso-1,2-Bis(dimethylamino)-1,2-diphenylethane by Oxidative C-C Coupling Reaction

2005

The title compound was obtained from the reaction of N,N-dimethylbenzylamine with n-butyl lithium and sulfur in tetrahydrofuran at room temperature. Its molecular structure was investigated by means of single crystal X-ray diffraction and quantum chemical DFT methods. The formation of meso-1,2-bis(dimethylamino)-1,2-diphenylethane is likely to be due to an unusual α-deprotonation of N,N-dimethylbenzylamine, instead of the well known ortho-lithiation, with a subsequent oxidative C-C coupling of the anions. Ab initio calculations of the corresponding α- and o-deprotonated anions of N,N-dimethylbenzylamine showed the former to be more stable than the latter, due to delocalisation of the negati…

CCDC 1917460: Experimental Crystal Structure Determination

2020

Related Article: A. Carel N. Kwamen, Marcel Schlottmann, David Van Craen, Elisabeth Isaak, Julia Baums, Li Shen, Ali Massomi, Christoph Räuber, Benjamin P. Joseph, Gerhard Raabe, Christian Göb, Iris M. Oppel, Rakesh Puttreddy, Jas S. Ward, Kari Rissanen, Roland Fröhlich, Markus Albrecht|2020|Chem.-Eur.J.|26|1396|doi:10.1002/chem.201904639

Unusual Regioselectivity in the Opening of Epoxides by Carboxylic Acid Enediolates

2008

Addition of carboxylic acid dianions appears to be a potential alternative to the use of aluminium enolates for nucleophilic ring opening of epoxides. These conditions require the use of a sub-stoichiometric amount of amine (10% mol) for dianion generation and the previous activation of the epoxide with LiCl. Yields are good, with high regioselectivity, but the use of styrene oxide led, unexpectedly, to a mixture resulting from the attack on both the primary and secondary carbon atoms. Generally, a low diastereoselectivity is seen on attack at the primary center, however only one diastereoisomer was obtained from attack to the secondary carbon of the styrene oxide.

Oligophenyls with Multiple Disulfide Bridges as Higher Homologues of Dibenzo[c,e][1,2]dithiin: Synthesis and Application in Lithium-Ion Batteries.

2020

Abstract Higher homologues of dibenzo[c,e][1,2]dithiin were synthesized from oligophenyls bearing multiple methylthio groups. Single‐crystal X‐ray analyses revealed their nonplanar structures and helical enantiomers of higher meta‐congener 6. Such dibenzo[1,2]dithiin homologues are demonstrated to be applicable to lithium‐ion batteries as cathode, displaying a high capacity of 118 mAh g−1 at a current density of 50 mA g−1.

Monodimensional Amorphous SnCo Arrays As High Performing Anodes for Lithium Ion Batteries

2012

Advanced Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer

2020

This paper presents three different techniques for efficiently powering an energy-autonomous wireless sensor (EAWS) through both energy harvesting (EH) and RF wireless power transfer (WPT). The aim of the paper is to provide effective strategies and techniques to reduce, as far as possible, the cost of wiring of the automotive production process due to the continuous and constant increase in the use of sensors. The techniques employ a highly integrated state-of-the-art, ultra-low power 2.5 mu W system-on-chip (SoC) system, designed for multi-source RF wireless energy harvesting and power transfer and are designed with the goal of minimizing and, where possible, eliminating the costly mainte…

Speed detection of battery-free nodes based on RF Wireless Power Transfer

2020

In the Internet of Things (IoT) era, Wireless Sensor Networks (WSNs) are rapidly increasing in terms of relevance and pervasiveness thanks to their notable real-time monitoring performance across several fields, including industrial, domestic, military, biomedical, commercial, environmental, and other sectors. A highly attractive implementation of WSNs is asset tracking with accurate data regarding the location and transportation conditions of goods, equipment, and the like. One highly promising application of WSNs along these lines is the remote speed monitoring of goods, ideally with battery-free sensor nodes that do not require any maintenance. This, however, represents a major challenge…