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