Preparation, Structure, Reactivity, Lewis Acidic and Fluorescence Properties of Arylpyridine Based Boron C,N-Chelates Featuring Weakly Coordinating Anions.

Herein, we present the preparation of a series of electronically and/or sterically distinct borenium-type species based on a simple 2-arylpyridine scaffold. Corresponding arylpyridine was firstly subjected to electrophilic borylation (BBr/i-PrNEt) and formed BBr chelate was reduced with LiAlH to yield arylpyridine boron dihydride. Elimination of one hydride led to Lewis acidic borenium-like products.

Factors controlling Mn and Zn contents in leaves of silver and downy birch in acidified soils of Central Europe and Norway.

In Central European mountain forests, foliar element concentrations (FECs) of manganese (Mn) in silver birch (Betula pendula Roth) are occasionally approximately 5000 mg kg and can represent stress for these plants. Factors controlling the Mn FECs in silver birch in Central Europe and downy birch (Betula pubescens Ehrh.) in Norway have not yet been fully deciphered.

Focus on Chemistry of the 10-Dioxane--7,8-dicarba-undecahydrido Undecaborate Zwitterion; Exceptionally Easy Abstraction of Hydrogen Bridge and Double-Action Pathways Observed in Ring Cleavage Reactions with OH as Nucleophile.

Ring cleavage of cyclic ether substituents attached to a boron cage via an oxonium oxygen atom are amongst the most versatile methods for conjoining boron -cages with organic functional groups. Here we focus on much less tackled chemistry of the 11-vertex zwitterionic compound [10-(-(CH-CH)O)--7,8-CBH] (), which is the only known representative of cyclic ether substitution at -cages, and explore the scope for the use of this zwitterion in reactions with various types of nucleophiles including bifunctional ones. Most of the nitrogen, oxygen, halogen, and sulphur nucleophiles studied react via nucleophilic substitution at the C1 atom of the dioxane ring, followed by its cleavage that produces six atom chain between the cage and the respective organic moiety.