Hydrogen bonds and halogen bonds can be used as synthetic vectors without structural interference as long as the primary molecular recognition events are designed around a careful combination of geometric and electrostatic complementarity. In addition, a one-step procedure for the synthesis of tectons equipped with powerful hydrogen- and halogen-bond donors is presented.

Only a few studies on the use of halogen bonding in catalysis have been published so far. Herein, (benz)imidazolium-based halogen bond donors are used as catalysts in a Michael addition reaction. The most potent catalyst, a rigid atropisomer featuring two iodobenzimidazolium moieties, provided a rate acceleration versus a reference compound of ca. 50.

Gold catalysis has, over the past decades, provided innovative organic transformations under mild conditions with high chemoselectivities. It receives steadily growing attention thanks to its wide synthetic applicability. The catalytically active form, [Ln-Au]+, of ligated gold complexes, [Ln-Au-Cl], is formed via halide abstraction. This typically achieved by anion exchange upon addition an ap...

It is known that halogen bonding is supported by so-called sigma holes on halides that interact with bases, but what are the limits of that interaction? How does the interaction depend on the group to which the halogen atom is bonded? To answer these questions, complexes of the form MH3X---Y (where M=C, Si, Ge, Sn, Pb; X= F, Cl, Br, I and Y are Lewis bases) were optimized and their energetics a...

The reactions of 1-aminoalkylphosphonic acids with bromine-water, chlorine-water and iodine-water were investigated. The formation of phosphoric(v) acid, as a result of a halogen-promoted cleavage of the Cα-P bond, accompanied by nitrogen release, was observed. The dephosphonylation of 1-aminoalkylphosphonic acids was found to occur quantitatively. In the reactions of 1-aminoalkylphosphonic aci...

A new approach towards highly enantioselective halogen-bonding catalysis has been developed. In order to circumvent the intrinsic issues of halogen-bond (XB) nature and consequent unresolved limitations in asymmetric catalysis, fine-tuned halogen--halogen interactions between substrate XB-donor were designed pre-organize catalyst’s cavity boost enantiocontrol. The present strategy exploits both...

Co-crystallisation of, in particular, 4-iodotetrafluorophenol with a series of secondary and tertiary cyclic amines results in deprotonation of the phenol and formation of the corresponding ammonium phenate. Careful examination of the X-ray single-crystal structures shows that the phenate anion develops a C=O double bond and that the C-C bond lengths in the ring suggest a Meissenheimer-like del...

Halogens are present in a significant number of drugs, contributing favorably to ligand-protein binding. Currently, the contribution of halogens, most notably chlorine and bromine, is largely attributed to halogen bonds involving favorable interactions with hydrogen bond acceptors. However, we show that halogens acting as hydrogen bond acceptors potentially make a more favorable contribution to...