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Cr-doped Hβ zeolite is found to have better catalytic performance than Hβ zeolite in the Friedel-Crafts acylation of anisole, with acetic anhydride conversion of over 99% and nearly 100% selectivity to furnish para-methoxyacetophenone under the optimized reaction conditions. This is attributed to the increase of weak and moderately strong acid sites, caused by the Cr addition. The formation of carbonaceous materials and their coating of the acid sites are believed to be the reasons for the deactivation of the reused Cr-doped Hβ zeolite, as indicated by the Brunauer−Emmett−Teller (BET) method, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and NH temperature-programmed desorption (NH-TPD) measurement results. The catalyst activity can be recovered by a subsequent calcination. [ABSTRACT FROM AUTHOR]

The molecule of the title compound, C15H24O2, lies across a mirror plane with the two tert-butyl substituents flanking the phenolic OH group in this hindered phenol. In the crystal structure, O—H⋯O hydrogen bonds between the benzyl OH group and the phenolic O atom link the mol­ecules into chains. [ABSTRACT FROM AUTHOR]

The title compound, C21H20N4O5S, crystallizes with two mol­ecules in the asymmetric unit. The crystal structure is stabilized by a network of C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C10H26N2O22+·2NO3−, comprises one half of an N-diprotonated ( R, S)-ethambutol cation, which lies about a centre of symmetry, and a nitrate anion. In the crystal structure, a two-dimensional network is formed via inter­molecular O—H⋯O and N—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C23H22N4O5S, is the key inter­mediate for the synthesis of tazobactam, a widely used β-lacta­mase inhibitor. The crystal structure is stabilized by inter­molecular O—H⋯N and N—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The article presents information on the synthesis and chemical structure of 4-Methyl-N-(3-nitrophenyl)benzenesulfonamide. C13H12N2O4S. The structure reveals that the two benzene rings are orthogonal to each other. The compound can be used to prepare a variety of sulfonamide drugs. Several molecules are linked through the N-H⋯O bonds into infinite chains which run across the plane of the crystal structure. The dihedral angle between two benzene rings is 92.4±.

The formation of the title compound, ( S)-2-ammonio-1-butanol (2 R,3 R)-tartrate, C4H12NO+·C4H5O6−, the ( S)-2-amino-1-butanol mol­ecule is converted to a cationic form containing a positively charged amino group, and the tartaric acid mol­ecule to a mono- or half-ionized tartrate anion. The structure is stabilized by a three-dimensional network of hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C10H28N2O10S2, was synthesized by the reaction of concentrated sulfuric acid with ( R, S)-ethambutol. The zwitterionic amino–sulfate system, protonated at both N atoms, lies about a centre of symmetry. The asymmetric unit also contains a solvent water mol­ecule. In the crystal structure, inter­molecular O—H⋯N and N—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network. [ABSTRACT FROM AUTHOR]

In the title structure, C10H26N2O22+·2NO3−, the ethambutol mol­ecule exists in the cationic form, having two protonated amine groups, and is charge-balanced by two nitrate anions. In the crystal structure, a two-dimensional network is formed via inter­molecular O—H⋯O and N—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C10H24N2O2, was synthesized by N-alkyl­ation of 1,2-dichloro­ethane with ( S)-2-amino-1-butanol. In the crystal structure, O—H⋯N and N—H⋯O link the mol­ecules into sheets in the bc plane. [ABSTRACT FROM AUTHOR]

In the formation of the title compound, C4H12NO+·C4H5O6−·H2O, the ( R)-2-amino-1-butanol mol­ecule is converted to a cationic form containing a positively charged amino group, and the tartaric acid mol­ecule to a mono- or half-ionized tartrate anion. The structure is stabilized by a three-dimensional network of hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title structure, C14H10O5, the angle between the planes formed by the 2,4-di­hydroxy­benzoyl and o-benzoic acid moieties is 87.12 (4)°. In addition to an intramolecular O—H⋯O hydrogen bond, intermolecular O—H⋯O hydrogen bonds (H⋯O = 1.76 and 1.89 Å) connect mol­ecules to form a two-dimensional network parallel to (10 ). [ABSTRACT FROM AUTHOR]

The title compound, C11H10N2O2S, crystallizes as a zwitterionic tautomer, N-(4-pyridinio)benzenesulfonamidate, with the pyridine N atom protonated and the amide N atom deprotonated. There is evidence for conjugation between the anionic N atom and the pyridinium ring. In the crystal structure, intermolecular N—H...N hydrogen bonds link the molecules into chains along the c axis. Weak C—H...O and C—H...π interactions further stabilize the structure. [ABSTRACT FROM AUTHOR]

The title compound, C18H19Br2N, was synthesized by N-alkyl­ation of 1-bromo­hexane with 3,6-dibromo-9 H-carbazole. The carbazole ring system is essentially planar and the n-hexyl chain is in the fully extended conformation. [ABSTRACT FROM AUTHOR]