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Enantioselective phosphorylation catalyzed by glycerol kinase (EC 2.7.1.30) facilitated the kinetic chiral resolution of 3-chloro-1,2-propanediol, 3-fluoro-1,2-propanediol, 3-butene-1,2-diol, and 1,2,4-butanetriol. Both enantiomers of each compound were isolated in free diol or triol form, in excellent enantiomeric purity (91 to >99.5% ee) and in moderate to good yield (60−94% of theoretical). The enantioselectivities of glycerol kinase from different sources were compared, using 1,2,4-butanetriol as the substrate. The effect of elevated temperatures on enzymatic activity, stability, and enantioselectivity were studied, and procedures for the isolation of diol and triol products were optimized. Glycerol kinase-catalyzed phosphorylation facilitated the three-step chemoenzymatic conversion of glycerol to (S)-1,2-O-isopropylideneglycerol in 83% yield and >99.5% ee).

2,4,8,10-Tetranitrobenzotriazolo[2,1-a]benzotriazole (TACOT), although thermally very stable and insensitive as an explosive, is susceptible to attack by nucleophiles. Reaction with azide ion results in displacement of nitro groups at the 4,10-positions, treatment with methoxide ion effects displacement of the hydrogen atom at the 1-position and scission of the remote triazole ring, while “vicarious nucleophilic amination” displaces all the aromatic hydrogens. 3,5,7-Trinitro-1,2,3-triazolo[2,1-a]benzotriazole and 3,5,7-trinitro-1,2,3-triazolo[1,2-a]benzotriazole are prepared readily by nitration of the parent triazolobenzotriazoles. However they are thermally less stable than TACOT and more sensitive to initiation by impact. Furthermore, attempted further nitration and reaction with nucleophiles such as azide and methoxide ions both effect scission of the triazole ring to leave 4,6-dinitrobenzotriazole.

The mechanism of hydrolysis of isopropenyl alpha- and beta-glucopyranosides (1 and 2, respectively) has been studied by temperature-dependent reaction kinetics, stereochemical analysis of products by (1)H NMR, solvent (18)O- and (2)H-labeling experiments, kinetic solvent deuterium isotope effects, and alpha-values for general acid catalysis. Compounds 1 and 2 are the first vinyl acetals to be shown to undergo hydrolysis exclusively by cleavage of the vinyl ether and not the acetal C-O bond. While both glucopyranosides undergo irreversible, rate-limiting C-protonation, 1 hydrolyzes approximately four times faster than 2 and has an enthalpy of activation that is 5.8 kcal mol(-)(1) lower than that of 2, suggesting that 1 is kinetically more basic than 2. Spectroscopic evidence indicates that conjugation of the glycosidic oxygen with the alkenyl double bond is greater in 1 than in 2, probably because of steric or conformational constraints.

Various anomerically pure isopropenyl α- and β-glycopyranosides have been synthesized and shown to undergo synthetically useful transglycosylation reactions with a variety of primary and secondary carbohydrate alcohols. Although stable when stored, isopropenyl glycosides are readily activated as glycosyl donors by a variety of electrophiles, including N-iodosuccinimide/triflic acid, trimethylsilyl triflate, and triflic anhydride. Under conditions that retard formation of the glycosyl cation, the reactivity of isopropenyl glycosides is diverted away from transglycosylation and toward electrophilic addition across the vinyl ether double bond.

New synthetic routes to the three isomeric tetranitrotoluenes 1-3 are described, including the previously unreported 2,3,4,5-tetranitrotoluene (1). Methods include peroxydisulfuric acid oxidation of trinitrotoluidines and hypophosphorous acid reduction of diazonium salts derived from tetranitrotoluidines. Synthesis of selected trinitrotoluidine precursors is also discussed

The condensation of formaldehyde, glyoxal, and benzylamine, in a stoichiometric ratio, leads to 2,4,6,8-tetrabenzyl-2,4,6,8-tetrabicyclo[3.3.0]octane (1d) in methanol solvent with formic acid catalyst. Six phenyl-substituted derivatives of 1d, as well as 2,4,6,8-tetraisopropyl-2,4,6,8-tetraazabyclo[3.3.0]octane (1c), have been prepared in high yields by this synthetic method. Some of the chemical behavior of the new compounds is discussed