Inorganic as well as organic base catalysis was found to be effective for diastereoselective Mannich additions of malonic acid derivatives to (SS)-N-(tert-butanesulfinyl)-3,3,3-trifluoroacetaldimine. In the presence of catalytic amounts of inorganic bases, n-BuLi or DMAP, the reaction gives the corresponding (R,SS)-β-aminomalonates in good yield and with diastereoselectivity up to 9/1 dr. In co...

Malonic acid half thioesters (MAHTs) and malonic acid half oxyesters (MAHOs) are shown to undergo decarboxylative nucleophilic addition reactions with ketone and aldehyde electrophiles in the presence of stoichiometric or catalytic quantities of triethylamine at room temperature. The ability to perform these reactions under metal-free conditions has enabled a detailed mechanistic analysis of th...

The formation of localized structures in the chlorine dioxide-idodine-malonic acid ~CDIMA! reactiondiffusion system is investigated numerically using a realistic model of this system. We analyze the onedimensional patterns formed along the gradients imposed by boundary feeds, and study their linear stability to symmetry-breaking perturbations ~Turing instability! in the plane transverse to thes...

organic acid occur as physiologic intermediates in variety of intracellular metabolic pathways, such as catabolism of aminoacid, mitochondrial β oxidation of fatty acids, tricarboxilic acid cycle, and cholestrol and fatty acid biosynthesis. the classical organic aciduria represent the pursuit of abnormalities of aminoacid degradation beyond deamination their diagnostic hallmark is an accumulati...

The stoichiometry of CO2 production during the ceric oxidation of various organic acids is measured under conditions with organic acid excess. Measurements utilize a photometric methodology. For anaerobic conditions stoichiometries [CO2]produced : [Ce(IV)]reduced of about 0 (malonic acid), 0.5 (e.g., glyoxylic acid), and 1.0 (oxalic acid) are found. Oxalic acid showed an oxygen-induced decrease...

Spontaneously evolving Turing structures in the chlorine dioxide-iodine-malonic acid reaction-diffusion system typically exhibit many defects that break the symmetry of the pattern. Periodic spatial forcing interacts with the Turing structures and modifies the pattern symmetry and wavelength. We investigate the role of the amplitude and wavelength of spatial periodic forcing on the hexagonal pa...

We study the mechanism of development of superlattice Turing structures from photochemically generated hexagonal patterns of spots with wavelengths several times larger than the characteristic wavelength of the Turing patterns that spontaneously develop in the nonilluminated system. Comparison of the experiment with numerical simulations shows that interaction of the photochemical periodic forc...