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The series of alkali-metal (Li, Na, K) complexes of the substituted benzyl anion 3,5-dimethylbenzyl (MeCHCH ) derived from 1,3,5-trimethylbenzene (mesitylene) have been coerced into monomeric forms by supporting them with the tripodal tetradentate Lewis donor tris(N,N-dimethyl-2-aminoethyl)amine, [N(CH CHNMe), MeTREN]. Molecular structure analysis by X-ray crystallography establishes that the cation-anion interaction varies as a function of the alkali-metal, with the carbanion binding to lithium mainly in a σ fashion, to potassium mainly in a π fashion, with the interaction toward sodium being intermediate between these two extremes. This distinction is due to the heavier alkali-metal forcing and using the delocalization of negative charge into the aromatic ring to gain a higher coordination number in accordance with its size. MeTREN binds the metal in a η mode at all times. This coordination isomerism is shown by multinuclear NMR spectroscopy to also extend to the structures in solution and is further supported by density functional theory (DFT) calculations on model systems. A MeTREN stabilized benzyl potassium complex has been used to prepare a mixed-metal ate complex by a cocomplexation reaction with tBuZn, with the benzyl ligand acting as an unusual ditopic σ/π bridging ligand between the two metals, and with the small zinc atom relocalizing the negative charge back on to the lateral CH arm to give a complex best described as a contacted ion pair potassium zincate.

Colourless needles of the 1 : 1 primary amine-phosphine oxide adduct CsH4SC(=N)NH2.0=P(NMe2)a3r e obtained in high yield simply by chilling a toluene solution of the two components; the solid-state structure of the highly stable adduct (which can be prepared in water, and which sublimes easily) consists essentially of dimers held by (amine) N-H...O and (amine)N-H...(heterocyclic) N hydrogen bonds. peerReviewed

Solid Li2S reacts with a solution of [graphic omitted]H and hexamethylphosphoramide (HMPA) in toluene to give [[graphic omitted]Li·µ2-HMPA]2·C6H4(OH)NH2, 1, in which two equivalents of the organic acid have been lithiated while a third equivalent has been stripped of its CS group and di-protonated; structurally, complex 1, which can also be prepared directly by reacting BunLi, [graphic omitted]H, HMPA and NH2C6H4OH in 2:2:2:1 amounts, is unique in having a heterobifunctional ligand (NH2C6H4OH) bridging two Li+ centres in the same molecule. peerReviewed

High-resolution FlowNMR was coupled to a continuous flow reactor to monitor polymer molecular weight evolution online by diffusion ordered NMR spectroscopy. Polymers were synthesized by reversible addition fragmentation chain transfer polymerization in continuous flow. The setup allows to target various polymer chain lengths in a dynamic manner without requiring additional purification or sample preparation. Obtaining molecular weight information in this manner is shown to be more accurate than classical SEC analysis at comparable measurement times, with relative errors around 5%. The authors are grateful to the Fonds Wetenschappelijk Onderzoek (FWO) for providing a SB scholarship for JHV, the Royal Society for a University Research Fellowship to UH (UF160458), and EPSRC for funding the Dynamic Reaction Monitoring Facility at the University of Bath (EP/P001475/1) and for the EPSRC Centre for Doctoral Training in Sustainable Chemical Technologies (EP/L016354/1, PhD studentship for IAT). We thank Joris Haven (Monash University), Maciek Kopec and John Lowe (University of Bath) for stimulating discussions. Junkers, T (corresponding author), Hasselt Univ, Martelarenlaan 42, B-3500 Hasselt, Belgium; Monash Univ, Sch Chem, Polymer React Design Grp, 19 Rainforest Walk,Bldg 23, Clayton, Vic 3800, Australia. u.hintermair@bath.ac.uk; tanja.junkers@monash.edu