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The synthesis for a single enantiomer timolol maleate based on an initial Jacobsen hydrolytic kinetic resolution of racemic epichlorohydrin and on the stereochemistry of the subsequent chemical transformations has been proposed. The feature of this synthesis is that both products of the kinetic resolution, ( R )-epichlorohydrin ( R )- 4 and ( S )-3-chloropropane-1,2-diol ( S )- 5 , have been utilized in the synthesis of the target, ( S )-timolol. The mirror stereochemical results can be obtained with the use of ( R , R )-salen Co(III) catalyst instead of ( S , S )-salen Co(III).

Asymmetric dihydroxylation of mono nitrophenyl allyl ethers leads to the corresponding non-racemic 3-(nitrophenoxy)-propane-1,2-diols 1a – c . As this takes place, regardless of the reagent used (AD-mix-α or AD-mix-β), the configuration of the predominant enantiomer for the para - and meta -nitrosubstituted products is opposite to the configuration of the ortho -nitrophenyl derivative. A correlation between the melting points and vibrational spectra of the racemic and enantiopure diols 1a – c allowed us to establish that all of the chiral substances investigated formed stable racemic compounds in the solid phase.

A series of enantiopure and racemic p -alkylphenyl glycerol ethers 1a – k were synthesized. A new, sensitive, and pictorial method of comparison of the IR spectra of solid enantiopure and racemic samples was developed to obtain preliminary information on the crystallization types of these compounds. In order to detect the subtle differences in the organization of the chiral solid phase, a new easily implemented approach, based on a chromatographic measuring of the relative abundance of the enantiomers in a single solution in equilibrium with a solid sample of arbitrary (0 n -Pr) and one borderline case (Alk = n -Bu) are disclosed. Higher members of the series of 1 (starting with an n -Bu derivative) are turned into liquid crystals upon melting; no significant differences between racemic and non-racemic samples were found. Only enantiopure methyl-, n -butyl, n -pentyl, n -hexyl, and n -heptyl substituted 1 were able to form supramolecular gels in hydrocarbon solvents; all racemic ethers 1 did not show such ability.

Popular chiral drugs, guaifenesin, methocarbamol, and mephenesin were investigated by single-crystal X-ray analysis both for enantiopure and racemic samples. The absolute configurations for all substances were established through Flack parameter method. The conglomerate-forming nature for the compounds was confirmed by equivalence of crystal characteristics of enantiopure and racemic samples. The molecular structures and crystal packing details were evaluated and compared with one another for all three investigated substances.

The muscle relaxant methocarbamol 2 and tranquilizer mephenoxalone 3, as well as intermediate cyclic carbonate 4, have been prepared in enantiopure form by starting from enantiopure guaifenesin 1 easily available by an entrainment resolution procedure. Thermal investigations reveal that 2 is probably a conglomerate forming substance, 3 forms a stable racemic compound, and 4 occupies an intermediate position. The enantiomeric excess of a binary phase eutectic point for these substances comprises 0%, 85%, and 10%, respectively.

The conglomerate-forming nature of 3-(2-hydroxyphenoxy)propane-1,2-diol was established by IR, DSC, and XRD methods; racemic diol could be resolved by a moderate efficiency preferential crystallization procedure.

The chiral drug methocarbamol, which is prone to spontaneous resolution, is an effective molecular hydrogelator as both an enantiomer and a racemate; the samples of methocarbamol having an intermediate enantiomeric composition generate clearly visible periodic structures (Liesegang rings) during the gelation process.

The interaction of (S)-glycidol with SOCl2 or SO2Cl2 in stoichiometric amounts leads to the formation of cyclic (4S)-chloromethyl sulfite or sulfate derivatives with the same enantiomeric purity; based on this reaction, a new procedure for the synthesis of (S)-propranolol was developed.