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If the rearrangement of metalated allyl ethers, e.g., I, is accomplished in the presence of potassium tert-butoxide, primary alkyl groups preferentially migrate to the unsubstituted allylic terminus (g-position). Enolates (Z)-R3CHR4CR1R2CH2CH:CHOLi and 1-v ...
During deamination, γ-amino acids can undergo concomitant decarboxylation. Aiming at studying the course of the involved reaction, the following γ-amino acids were synthesized and characterized: (–)-3c-amino-1,2,2-trimethylcyclopentane-1r-carboxylic acid ( ...
Recent experiments have confirmed the importance of nuclear quantum effects even in large biomolecules at physiological temperature. Here we describe how the path integral formalism can be used to describe rigorously the nuclear quantum effects on equilibr ...
The path integral methodology for computation of the equilibrium isotope effect is described and applied to three [1,5] sigmatropic hydrogen shift reactions. An efficient estimator for the derivative of the free energy is used, which shortens the computati ...
A general and rigorous methodology to compute the quantum equilibrium isotope effect is described. Unlike standard approaches, ours does not assume separability of rotational and vibrational motions and does not make the harmonic approximation for vibratio ...
At low temperature and in the presence of an acid catalyst, SO2 adds to 1,3-dienes equilibrating with the corresponding 3,6-dihydro-1,2-oxathiin-2-oxides (sultines). These compounds are unstable above -60 degrees C and equilibrate with the more stable 2,5- ...
To accelerate reactive events in mol. dynamics simulations we introduce a general bias potential scheme which depends only on the electronic degrees of freedom of the reactive system. This electronic reaction coordinate, which is expressed in terms of a pe ...
The goal of this thesis was to find conditions to form C-C double bond and single bond using sulfonyl derivativies, which are arising from the Vogel's oxyallylation cascades. In a second chapter, it is shown that 2-methylprop-2-ene-1-sulfonyl fluorides can ...
2-Methylprop-2-ene-1-sulfonyl fluorides can be easily prepared via the ene reaction of methallylsilanes and SO2. In the presence of a base, aldehydes and 2-methylprop-2-ene-1-sulfonyl fluorides give 1.3-(E) and (Z)-dienes. Their (Z) --> (E) isomerization b ...
The reactivity of sulfur dioxide toward variously substituted butadienes was explored in an effort to define the factors affecting the competition between the hetero-Diels-Alder and cheletropic additions. At low temperature (< -70degrees), 1-alkyl-substitu ...