Alexander V. Pashagin

Three different types of chirality-driven crystallization within the series of uniformly substituted phenyl glycerol ethers.

Seven chiral arylglycerol ethers 2-R-C(6)H(4)-O-CH(2)CH(OH)CH(2)OH (R = H, Me, Et, Allyl, n-Pr, i-Pr, tert-Bu) were synthesized in racemic and scalemic form. The IR spectra, melting points, and enthalpies of fusion for racemic and scalemic samples of every species were measured, the entropies of enantiomers mixing in the liquid state and Gibbs free energies of a racemic compound formation were derived and binary phase diagrams were reconstructed for the whole family. Solid racemic compounds stabilities were ranked for the four substances. Spontaneous resolution was established for the registered chiral drug mephenesin and its ethyl analogue. Metastable anomalous conglomerate, forming crystals having three independent R* and one independent S* molecules in the unit cell, is formed during solution crystallization of tert-butyl derivative; metastable phase transforms slowly into traditional racemic conglomerate.

Reactions of 4-chloromethyl-1,3,2-dioxathiolane 2-oxides with sodium phenoxide. A reinvestigation

The reactions of 4-chloromethyl-1,3,2-dioxathiolane 2-oxides with PhONa in EtOH are accompanied by ring opening under the action of the ethoxide ion rather than leading to a rearrangement of the starting molecule as has been assumed previously. Under conditions precluding competition with other nucleophiles, the phenoxide anion smoothly replaces the chlorine atom in chloromethyl-substituted cyclic sulfites.

New approach to cyclic sulfites and sulfates through reactions of sulfur oxychlorides with glycidols

Reactions of 2,3-epoxyalcohols (glycidols) with thionyl chloride or sulfuryl chloride afford cyclic sulfites or sulfates, respectively. These reactions yield predominantly 4-chloroalkyl-1,3,2-dioxathiolane oxides. The configuration of the C(4) atom in the latter compounds exactly corresponds to that of the C(2) atom of the parent glycidol, whereas the configuration of the exocyclic atom is almost completely reversed with respect to that of the C(3) atom of the precursor.

New reaction of glycidols with oxalyl chloride and phosgene—an approach to cyclic esters

Abstract2,3-Epoxy alcohols (glycidols) react with carboxylic acid dichlorides to form cyclic esters of 3-chloro-1,2-diols. The reaction proceeds with complete retention of the configuration of the C(2) atom of the initial glycidol and with predominant (but not complete) inversion of the configuration of the C(3) atom in the final heterocycle.

Synthesis of enantiomerically pure 3-aryloxy-2-hydroxypropanoic acids, intermediate products in the synthesis of cis-4-Aminochroman-3-ols

Oxidation of accessible (R)-3-chloropropane-1,2-diol to (R)-3-chloro-2-hydroxypropanoic acid and subsequent reaction of the latter with ortho-substituted sodium phenoxide gave a number of enantiomerically pure 3-aryloxy-2-hydroxypropanoic acid which are intermediate products in the synthesis of nonracemic 4-aminochroman-3-ols.