Tri(hetero) substituted Carbonium Ions. VI. An Anomalous Reaction of 2-Methylthio-1,3-dithiolanylium Ion withN,N-Dimethyldithiocarbamate Anion

Extended Hückel Theory. IV. Carbonium Ions

The Role of Carbonium Ions in Color Reception

It is a fundamental property of conjugated systems to accept a proton or Lewis acid and form a stable carbonium ion. Polyenes that are protonated or add Lewis acids in this manner undergo substantial red shifts. For example, vitamin A(1) acetate absorbs at 350 mmicro in neutral and at 650 mmicro in acidic benzene solution. The fundamental basis for absorption of polyene systems was described in...

Identification of Carbonium and Carbenium Ions by QTAIM

A ferramenta de Gassman-Fentiman da demanda crescente de elétrons foi usada para identificar íons carbênios e íons carbônios. Contudo, devido ao seu entendimento ambíguo, ela foi pivô de uma disputa histórica. Nós aplicamos a metodologia da Teoria Quântica de Átomos em Moléculas QTAIM para caracterizar íons carbênios e íons carbônios de uma forma mais eficaz e mais fácil. Essa metodologia pode ...

Metastable Ions as a Guide to Reaction Mechanisms. Loss of ’OH from Substituted Nitrobenzene Molecular Ions

für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution 4.0 International License. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht: Creative Commons Namen...

Reaction of oxide radical ion ( O . ¡ ) with substituted pyrimidines

Pulse radiolysis technique has been used to investigate the reaction of oxide radical ion (O.¡) with 4,6-dihydroxy-2-methyl pyrimidine (DHMP), 2,4-dimethyl-6-hydroxy pyrimidine (DMHP), 5,6-dimethyl uracil (DMU) and 6-methyl uracil (MU) in strongly alkaline medium. The second-order rate constants for the reaction of O.¡ with these compounds are in the range 2–5£ 108 dm3mol¡1 s¡1. The transient a...