Hydrogen complexes stability

Density functional theory study of aqueous-phase rate acceleration and endo/exo selectivity of the butadiene and acrolein Diels-Alder reaction72 shows that approximately 50% of the rate acceleration and endo/exo selectivity is attributed to hydrogen bonding and the remainder to bulk-phase effects, including enforced hydrophobic interactions and cosolvent effects. This appears to be supported by the experimental results of Engberts where a pseudothermodynamic analysis of the rate acceleration in water relative to 1-propanol and 1-propanol-water mixtures indicates that hydrogen-bond stabilization of the polarized activated complex and the decrease of the hydrophobic surface area of the reactants during the activation process are the two main causes of the rate enhancement in water.13... 

Metal hydrides containing transition metal (TM)-hydrogen complexes, with the transition metal in a formally low oxidation state, are of fundamental interest for clarifying how an electron-rich metal atom can be stabilized without access to the conventional mechanism for relieving the electron density by back-donation to suitable ligand orbitals. By reacting electropositive alkali or alkaline earth metals ( -elements) with group 7, 8, 9, and 10 transition metals in... 

I Iliopoulos, R Audebert, C Quivoron. Reversible polymer complexes stabilized through hydrogen bonds. In P Russo, ed. Reversible Polymeric Gels and Related Systems. ACS Symp Ser 350. Washington, DC American Chemical Society, 1987, pp 72-86. 

Toropov AA, Toropova AP (2002) QSPR modeling of complex stability by optimization of correlation weights of the hydrogen bond index and the local graph invariants. Russ. J. Coord. Chem. 28 877-880. 

ILIOPOULOS ET AL. Polymer Complexes Stabilized Through Hydrogen Bonds 73... 

Beijer FH, Sijbesma RP, Vekemans JAJM, Meijer EW, Kooijman H, Spek AL. Hydrogen-bonded complexes of diaminopyridines and diaminotriazines opposite effect of acylation on complex stabilities. J Org Chem 1996 61 6371-6380. 

Template polymerization based on hydrogen bonded interpolymer complexes has also been studied by Van de Grampel et al. [100]. Crosslinked PMAA networks were used as templates for the polymerization of N-vinylimidazole (Vim) which is known to form complexes with PMAA. The effects of solvent nature on the stability of the PMAA-PNVP complex have been studied by comparing complex stability in aqueous and organic solvents [101], In water, since the hydrophilic carboxylic acid groups of the PMAA were... 

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