Titanosilicates (Ti-SiO2) are well-known catalysts for the epoxidation of olefins. Isolated Ti inserted in silica framework tetrahedral coordination active species. Recently, adjusting hydrophobic/hydrophilic balance such catalysts’ surfaces has appeared as a promising tool to further boost their performance. However, via one-pot classical sol-gel generally leads decrease dispersion and/or coll...

the mesoporous molecular sieve mcm-41 was covalently grafted with 3-chloropropyl trimethoxylsilane and then was reacted with [cr(salpr)(h2o)]cl, (salpr = n,n'-bis(3-salicylidenaminopropyl)amine) to afford mcm-41 containing cr(salpr) moiety, cr(salpr)mcm-41. powder x-ray diffraction and nitrogen adsorption-desorption analyses revealed that not only the textural characteristics of the support wer...

ab initio calculations at hf/6-31g* level of theory for geometry optimization and mp2/6-31g*//hf/6-31g*for total energy calculation are reported for z-cyclooctene (1). the most favorable conformation of 1 is theunsymmetric boat-chair (1-bc) geometry. potential energy profiles for two different boat-chair/boat-chairinterconversion processes were calculated. the process via a chair transition sta...

The synthesis of trans-[{Rh(μ-Cl)(CO)(coe)}2] (1) was described by Varshavsky et al. some years ago [1, 2], but no crystal structure of this compound was reported. In an attempt to probe a possible convenient synthesis of [{Rh(μ-Cl)(CO)2}2] from the precursor [{Rh(μ-Cl)(coe)2}2] and carbon monoxide in diethyl ether, we found that the target complex was not available by this method. Instead, the...

Despite the great advances in solid-phase peptide synthesis (SPPS), incorporation of certain functional groups into sequences is restricted by compatibility building blocks with conditions used during SPPS. In particular, introduction highly reactive modern bioorthogonal reactions peptides remains elusive. Here, we present an optimized synthetic protocol enabling installation two strained dieno...