Layered birnessite-type manganese oxides have been synthesized by sol−gel reactions involving KMnO4 or NaMnO4 with glucose. These microporous manganese oxides are designated as octahedral layer materials, K-OL-1 and Na-OL-1, because their layered structure consists of edge-shared MnO6 octahedra. The interlayer regions are occupied by alkali metal cations and water molecules. K-OL-1 and Na-OL-1 have been characterized by elemental analysis, powder X-ray diffraction, scanning electron microscopy, FT-IR spectroscopy, and Auger electron spectroscopy. The empirical formula of K-OL-1 has been determined to be K0.28MnO1.96(H2O)0.19. An interlayer spacing of 7 Å, typical of natural and synthetic birnessites, has been measured by X-ray diffraction. The sol−gel synthesis of K-OL-1 is carried out with concentrated aqueous solutions of glucose and KMnO4 in a 1.5:1 mole ratio. Diluted reaction mixtures produce flocculent gels or precipitates which yield other manganese oxide phases such as cryptomelane and Mn2O3. The synthesis appears to be general for reactions of KMnO4 with a variety of sugars as well as other polyalcohols such as ethylene glycol, glycerol, and poly(vinyl alcohol). Reactions between NaMnO4 and glucose yield two related Na-OL-1 products. A procedure analogous to the K-OL-1 synthesis generates layered sodium birnessite materials with 5.5 and 7 Å interlayer distances. The 7 Å Na-OL-1 is obtained exclusively by hydrating the mixture of products. The 5.5 Å Na-OL-1 is prepared by calcining the Na-OL-1 xerogel at 800 °C instead of the typical 400 °C temperature. Both K-OL-1 and Na-OL-1 undergo significant yet incomplete cation extraction and ion exchange with monovalent and divalent cations.

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Sodium 5‐nitrotetrazolate dihydrate (NaNT) is a useful precursor compound for the synthesis of lead‐free primary explosives; however, currently employed syntheses for the compound are tedious, dangerous, and plagued by impurities. Through comprehensive analysis, we elucidate the identity of the most detrimental impurities and further report an improved procedure for preparation of NaNT, which greatly improves the purity, while avoiding the handling of acid copper(II) nitrotetrazolate, a highly sensitive explosive intermediate. In the new procedure, 5‐aminotetrazole is diazotized with sodium nitrite, cupric sulfate, and nitric acid. Copper is precipitated as its oxide and the aqueous solution evaporated. After soxhlet extraction with acetone, large crystals of NaNT are obtained. The prepared material is suitable for preparation of lead azide replacement DBX‐1 [copper(I) 5‐nitrotetrazolate] as evidenced by successful use in M55 stab detonators.

Carbonyldiimidazole (CDI) was found to mediate the Lossen rearrangement of various hydroxamic acids to isocyanates. This process is experimentally simple and mild, with imidazole and CO(2) being the sole stoichiometric byproduct. Significant for large-scale application, the method avoids the use of hazardous reagents and thus represents a green alternative to standard processing conditions for the Curtius and Hofmann rearrangements.

Many years ago anidulafungin 1 was identified as a potentially useful medicine for the treatment of fungal infections. Its chemical and physical properties as a relatively high molecular weight semisynthetic derived from echinocandin B proved to be a significant hurdle to its final presentation as a useful medicine. It has recently been approved as an intravenous treatment for invasive candidaisis, an increasingly common health hazard that is potentially life-threatening. The development and commercialization of this API, which is presented as a molecular mixture of anidulafungin and D-fructose is described. This includes, single crystal X-ray structures of the starting materials, the echinocandin B cyclic-peptide nucleus (ECBN • HCl) and the active ester 1-({[4′′-(pentyloxy)-1,1′:4′,1′′-terphenyl-4-yl]carbonyl}oxy)-1H-1,2,3-benzotriazole (TOBt). Details of the structure and properties of starting materials, scale-up chemistry and unusual crystallization phenomena associated with the API formation are discussed.