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The synthesis of dendrimers containing up to six different functional groups by multistep one-pot reactions involving a selective manipulation and deprotection strategy is described by E. E. Simanek and M. B. Steffensen in their Communication on the following pages.

Competition reactions for the substitution of monochlorotriazines with different amines provide relative reactivity data that can be used to identify new groups for the chemoselective syntheses of dendrimers based on melamine. Target 1 is prepared using a one-pot per generation strategy without protecting group manipulations or functional group interconversions.

ABSTRACT:A comprehensive and chronological account of dendrimers based on [1,3,5]-triazines is provided. Synthetic strategies to install the triazine through cycloaddition, cyclotrimerization, and nucleophilic aromatic substitution of cyanuric chloride are discussed.Motivations and applications of these architectures are surveyed, including the preparation of supramolecular assemblies in the solution and solid states and their use in medicines, advanced materials, and separations when anchored to solid supports. V

Single-molecule approaches to chemical reaction analysis can provide information that is not accessible by studying ensemble systems. Changes in the molecular structures of compounds tethered to the inner wall of a protein pore are known to affect the current carried through the pore by aqueous ions under a fixed applied potential. Here, we use this approach to study the substitution reactions of arsenic(III) compounds with thiols, stretching the limits of the protein pore technology to track the interconversion of seven reaction components in a network that comprises interconnected Walden cycles. Single-molecule pathway analysis of 'allowed' and 'forbidden' reactions reveals that sulfur-sulfur substitution occurs with stereochemical inversion at the arsenic centre. Hence, we demonstrate that the nanoreactor approach can be a valuable technique for the analysis of dynamic reaction systems of relevance to biology.