27 research outputs found
Bis(4-nitrophenyl) 1,3-phenylenedimethylene dicarbonate
In the title molecule, C22H16N2O10, the dihedral angles between the benzene rings of the 4-nitrophenyl groups and the central benzene ring are 32.7 (1) and 34.7 (1)°, while the dihedral angle between the two benzene rings of the 4-nitrophenyl groups is 3.6 (2)°. In the crystal structure, weak intermolecular C—H⋯O hydrogen bonds link molecules into centrosymmetric dimers
Di-tert-butyl cyclohex-2-ene-1,4-diyl dicarbonate
In the title molecule, C16H26O6, the central cyclohexene ring is in a half-chair conformation. The carbonyl groups are in a trans arrangement with respect to each other and the dihedral angle between the mean planes of the carbonate groups is 10.8 (2)°
2,5-Dimethylhexane-2,5-diyl bis(4-nitrophenyl) dicarbonate
The title structure, C22H24N2O10, contains two independent centrosymmetric molecules. The only significant difference between the molecules is the dihedral angle between the unique carbonate group (–O—CO2–) and the benzene ring, the values being 77.35 (8) and 66.42 (8)°. The crystal structure is stabilized by weak intermolecular C—H⋯O hydrogen bonds
3-Methyl-1H-pyrrolo[2,1-c][1,4]oxazin-1-one
In the title molecule, C8H7NO2, all the non-H atoms lie essentially in the same plane (r.m.s. deviation = 0.019 Å) In the crystal structure, weak intermolecular C—H⋯O interactions link molecules into chains along [100]. In addition, there are π–π stacking interactions between molecules related by the c-glide plane, with alternating centroid–centroid distances of 3.434 (2) and 3.639 (2) Å
trans-Cyclohexane-1,4-diyl bis(4-nitrophenyl) dicarbonate
In the title crystal structure, C20H18N2O10, there are two independent molecules, both of which lie on crystallographic inversion centres. In one molecule the 4-nitrophenyl dicarbonate groups are substituted in equatorial (A
eq) positions of the chair-form cyclohexane ring while in the other molecule the substitution is axial (B
ax). The dihedral angles between the atoms of the symmetry-unique carbonate group (O=CO2—) and benzene ring for each molecule are 47.3 (1)° for A
eq and 11.7 (2)° for B
ax. In B
ax, this facilitates the formation of a weak intramolecular C—H⋯O hydrogen bond, while the packing is stabilized by weak intermolecular C—H⋯O interactions
trans-Cyclohex-2-ene-1,4-diyl bis(4-nitrophenyl) dicarbonate
Although the title molecule, C20H16N2O10, does not possess molecular inversion symmetry, it lies on a crystallographic inversion centre which imposes disorder on the central cyclohexene ring. In addition, the cyclohexene ring has non-symmetry-related disorder over two sites, with the ratio of the major and minor components being 0.54:0.46. The overall effect is to produce four disorder components for the atoms of the cyclohexene ring. The side chain is perfectly ordered and the dihedral angle between the atoms of the carbonate group (O=CO2—) and the benzene ring is 72.99 (6)°
A Simple, Rapid and Mild One Pot Synthesis of Benzene Ring Acylated and Demethylated Analogues of Harmine under Solvent-free Conditions
A simple, rapid, solvent-free, room temperature one pot synthesis of benzene ring acylated and demethylated analogues of harmine using acyl halides/acid anhydrides and AlCl3 has been developed. Eight different acyl halides/acid anhydrides were used in the synthesis. The resulting mixture of products was separated by column chromatography to afford 10- and 12-monoacyl analogues, along with 10,12-diacyl-11-hydroxy products. In five cases the corresponding 10-acyl-11-hydroxy analogues were also obtained. Yields from the eight syntheses (29 products in total) were in the 6-34% range and all compounds were fully characterized