Steric effects of phosphorus ligands in organometallic chemistry and homogeneous catalysis

The Huckel theory, with an extended basis set consisting of 2s and 2p carbon and 1s hydrogen orbitals, with inclusion of overlap and all interactions, yields a good qualitative solution of most hydrocarbon conformational problems. Calculations have been performed within the same parametrization for nearly all simple saturated and unsaturated compounds, testing a variety of geometries for each. Barriers to internal rotation, ring conformations, and geometrical isomerism are among the topics treated. Consistent σ and π charge distributions and overlap populations are obtained for aromatics and their relative roles discussed. For alkanes and alkenes charge distributions are also presented. Failures include overemphasis on steric factors, which leads to some incorrect isomerization energies; also the failure to predict strain energies. It is stressed that the geometry of a molecule appears to be its most predictable quality.

An Extended Hückel Theory. I. Hydrocarbons

Some aspects of the surface chemistry of carbon blacks and other carbons

The rate of exchange of peptide group NH hydrogens with the hydrogens of aqueous solvent is sensitive to neighboring side chains. To evaluate the effects of protein side chains, all 20 naturally occurring amino acids were studied using dipeptide models. Both inductive and steric blocking effects are apparent. The additivity of nearest-neighbor blocking and inductive effects was tested in oligo- and polypeptides and, surprisingly, confirmed. Reference rates for alanine-containing peptides were determined and effects of temperature considered. These results provide the information necessary to evaluate measured protein NH to ND exchange rates by comparing them with rates to be expected for the same amino acid sequence is unstructured oligo- and polypeptides. The application of this approach to protein studies is discussed.

Primary Structure Effects on Peptide Group Hydrogen Exchange

Ranging from the physics of elementary particles to the structure of viruses, the subject matter of this book stresses the importance of optical activity and chirality in modern science and will be of interest to a wide range of scientists. Using classical and quantum methods with a strong emphasis on symmetry principles, the volume develops the theory of varied optical activity and related phenomena from the perspective of molecular scattering of polarized light. First Edition Hb (1983): 0-521-24602-4

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Molecular Light Scattering and Optical Activity

Of course, from childhood to forever, we are always thought to love reading. It is not only reading the lesson book but also reading everything good is the choice of getting new inspirations. Religion, sciences, politics, social, literature, and fictions will enrich you for not only one aspect. Having more aspects to know and understand will lead you become someone more precious. Yea, becoming precious can be situated with the presentation of how your knowledge much.

Melvin S. Newman

Papers

Steric effects in organic chemistry

The Synthesis and Resolution of Hexahelicene1

The Conversion of Phenols to Thiophenols via Dialkylthiocarbamates1

A NEW REAGENT FOR RESOLUTION BY COMPLEX FORMATION; THE RESOLUTION OF PHENANTHRO-[3,4-c]PHENANTHRENE1

The Chemical Composition of Technical DDT1