The impact of agostic interactions (i.e., 3-center-2-electron M-H-C bonds) on the structures and reactivity of organotransition metal compounds is reviewed.

https://www.pnas.org/content/pnas/104/17/6908.full.pdf

Agostic interactions in transition metal compounds

Cyclic peptides containing biologically active hormone sequences are suitable models for studying conformation-activity relationships. In such models the usual flexibility of peptide chains is reduced by their cyclic arrangement. However, conformational analysis of such systems by experimental means is possible only if a single conformer predominates at equilibrium, and criteria for this are put forward. NMR spectroscopic methods, including many recent advances, are discussed in relation to their ability to contribute to peptide conformational analysis.

Conformation and Biological Activity of Cyclic Peptides

Palaeoclimate studies have revealed the general high-frequency instability of Late Pleistocene climate—for example, the so-called Dansgaard–Oeschger and Heinrich events—on timescales of a few millennia, centuries or even decades1,11. Here we present evidence for a general relationship between low-latitude monsoonal climate variability and the rapid temperature fluctuations of high northern latitudes that are recorded in the Greenland ice records. Sediment cores from the northeastern Arabian Sea show laminated, organic-carbon-rich bands, reflecting strong monsoon-induced biological productivity, that correlate with the mild interstadial climate events in the northern North Atlantic region. In contrast, periods of lowered southwest monsoonal intensity, indicated by bioturbated, organic-carbon-poor bands, are associated with intervals of high-latitude atmospheric cooling and the injection of melt water into the North Atlantic basin. Our records suggest that Dansgaard–Oeschger and Heinrich events are strongly expressed in low-latitude (monsoonal) climate variability, suggesting the importance of common forcing agents such as atmospheric moisture and other greenhouse gases.

Correlation between Arabian Sea and Greenland climate oscillations of the past 110,000 years

Structure of 3-aminopropyl triethoxy silane on silicon oxide

N-silylated benzamidines: versatile building blocks in main group and coordination chemistry

https://pure.rug.nl/ws/files/3398750/1986OrganometallicsdenHaan.pdf

Synthesis of Monomeric Permethylyttrocene Derivatives. The Crystal Structures of Cp*2YN(SiMe3)2 and Cp*2YCH(SiMe3)2

https://pure.tue.nl/ws/files/1964844/620846.pdf

Low-temperature oligomerization of small olefins on zeolite H-ZSM-5. An investigation with high-resolution solid-state 13C-NMR

Solid-state silicon-29 and carbon-13 NMR spectroscopy using cross-polarization and magic-angle-spinning techniques to characterize 3-chloropropyl and 3-aminopropyl-modified silica gels

A high-resolution solid-state29 Si n.m.r. study of ZSM—5 type zeolites

Cross-polarization magic-angle 13C n.m.r. spectroscopy has been used for the first time to investigate the structure and position of organic bases occluded in ZSM-5-type zeorlites.

/pdf/an-investigation-into-the-structure-and-position-of-organic-44ewes53wb.pdf

Gary R. Hays

Papers

Synthesis of Monomeric Permethylyttrocene Derivatives. The Crystal Structures of Cp2YN(SiMe3)2 and Cp2YCH(SiMe3)2

Low-temperature oligomerization of small olefins on zeolite H-ZSM-5. An investigation with high-resolution solid-state 13C-NMR

Solid-state silicon-29 and carbon-13 NMR spectroscopy using cross-polarization and magic-angle-spinning techniques to characterize 3-chloropropyl and 3-aminopropyl-modified silica gels

A high-resolution solid-state29 Si n.m.r. study of ZSM—5 type zeolites

An investigation into the structure and position of organic bases in ZSM-5-type zeolites by high-resolution solid-state 13C n.m.r. spectroscopy