Unprecedented metalated phosphonite boranes were prepared from PH-substituted precursors and silyl amides. Althoughp otassium derivatives were thermally stable and could even be isolated and structurally characterised,l ithiated analogues proved to be unstable towards self-condensation under cleavage of LiOR at ambient temperature. Reaction studies revealed that the metalated phosphonite boranes exhibit ambiphilic character. Their synthetic potential as nucleophilic building blocks was demonstrated in the synthesis of the first stannylated phosphonite representing an ew structural motif in phosphine chemistry.

A linear solution‐phase synthesis of branched oligonucleotides with adamantane as core has been developed. The method uses conventional phosphoramidites only, achieves chain assembly without chromatography of intermediates, and overcomes the low reactivity of adamantane‐1,3,5,7‐tetraol as core. The assembly of four‐arm hybrids with up to 32 nucleotides total was performed, with monodisperse products of up to 10 kDa in size. Overall yields of 20 % over 19 steps (hexamer arms) and 11 % over 25 steps (octamer arms) of HPLC‐purified compounds were obtained. The adamantane‐based hybrids show more DNA‐dominated assembly properties than their analogues with larger lipophilic cores. Reversible formation of macroscopic amounts of materials through hybridization was achieved, both for self‐complementary systems and two‐hybrid systems with two non‐self‐complementary DNA sequences.

Cationic imidazolio-phosphines show two-sided reactivity towards bases, undergoing either Brønsted-type proton transfer to imidazolio-phosphides or autocatalytic Lewis acid/base reaction cascades to yield P-free imidazolium ions and oligophosphines.

The reversible reaction of H2 with a bis-phosphenium complex of chromium provides a rare example of 3d transition metal/phosphenium cooperativity. Photolysis induces the activation of H2 and yields a spectroscopically...

The Front Cover shows the starting materials of a solution‐phase synthesis of branched oligonucleotides and a series of reaction vessels of increasing size, illustrating the fact that there is a new, efficient, and scalable DNA synthesis that provides macroscopic amounts of branched DNA. While traditional solid‐phase synthesis of DNA is expensive to scale up, the new method readily produces hundreds of milligrams of branched oligonucleotides in a cost‐efficient manner using conventional laboratory equipment. This is important for producing DNA‐based materials in macroscopic quantities. More information can be found in the https://doi.org/10.1002/ejoc.201700686

Reaction of the iodide salt of a secondary imidazolio-iodophosphine [(L)PHI]I (L+ = 1,3-diarylimidazolium-yl) with an imidazolio-phosphide (L)PH in the presence of GaI3 afforded the isolable salt of a dicationic, bis(imdiazolio)-substituted...

Reaction of an imidazolio-phosphide with a N-heterocyclic bromo-borane and NaH afforded a neutral analogue of a phosphamethine cyanine cation. DFT studies were used to analyse the dative bonding across P–C/B...

Dedicated to Professor Dr. Frank Uhlig on the occasion of his 60th birthday.Reactions of primary imidazolio-phosphides ("imidazolylidenephosphinidenes") with R 2 SnCl 2 yield as main products spectroscopically detectable Lewis pairs which undergo base-induced dehydrochlorination in the presence of excess dichlorostannane to afford zwitterionic chloride adducts of distannylated imidazolio-phosphines. In contrast, reactions with R 3 SnCl proceed under dismutation to furnish mixtures containing imidazolium salts and stannylated (oligo)phosphines P(SnR 3 ) 3 and P 7 (SnR 3 ) 3 , respectively. DFT studies were used to rationalize the divergent behavior based on the presumption that the reactions proceed under thermodynamic control and the products observed represent the most stable species under the specific reaction conditions. Computational simulation of selected reaction steps provides a model mechanism for Lewis-acid promoted creation of PP-bonds, which is a prerequisite for oligophosphine formation. The computational studies further highlight parallels between reactions of imidazolio-phosphides with Lewis and Brønsted acids, and allow also to extrapolate the behavior of the P-nucleophiles towards other electrophiles than organotin chlorides.