Isolation of 3-amino-4-nitro-benzyl acetate: evidence of an undisclosed impurity in 5-amino-2-nitro-benzoic acid.
ABSTRACT: Yellow crystals of the title compound 3-amino-4-nitro-benzyl acetate, C9H10N2O4, were isolated from the reaction of acetic anhydride with (5-amino-2-nitro-phen-yl)methanol, prepared from reduction of commerically available 5-amino-2-nitro-benzoic acid with borane-THF. The mol-ecule is essentially planar (r.m.s. deviation = 0.028?Å). The mol-ecules are linked by inter-molecular N-H?O hydrogen-bonding inter-actions between the carbonyl and amine groups, forming a zigzag chain along the b-axis direction lying in a plane parallel to (-102). The chains are stacked along the c axis by ?-? inter-actions [centroid-centroid distances = 3.6240?(3) and 3.5855?(4)?Å]. A strong intra-molecular N-H?O hydrogen-bonding inter-action is observed between the nitro group and the amine group [2.660?(2)?Å].
Project description:In the title compound, C(10)H(11)N(3)O(2), the nitro group is essentially coplanar with the aromatic ring [dihedral angle = 1.3?(3)°] and forms an intra-molecular amine-nitro N-H?O hydrogen bond. In the crystal, weak inter-molecular aromatic C-H?O(nitro) hydrogen bonds link the mol-ecules. Weak aromatic ring ?-? inter-actions [minimum ring centroid separation = 3.7744?(13)?Å] are also present.
Project description:In the title compound, C(6)H(7)N(2)O(2) (+)·I(3) (-)·H(2)O, the triiodide anions form two-dimensional sheets along the a and c axes. These sheets are separated by the 4-nitro-anilinium cations and water mol-ecules, which form part of an extended hydrogen-bonded chain with the triiodide along the c axis, represented by the graph set C(3) (3)(14). The second important hydrogen-bonding inter-action is between the nitro group, the water mol-ecule and the anilinium group, which forms an R(2) (2)(6) ring and may be the reason for the deviation of the torsion angle between the benzene ring and the nitro group from 180 to 163.2?(4)°. These two strong hydrogen-bonding inter-actions also cause the benzene rings to pack off-centre from one another, with an edge-on-edge ?-? stacking distance of 3.634?(6)?Å and a centroid-centroid separation of 4.843?(2)?Å.
Project description:In the title compound, C14H8N4O6, the benzoxazin-4-one fused-ring system (r.m.s. deviation = 0.018?Å) is coplanar with the attached benzene ring [dihedral angle = 0.81?(4)°], there being an intra-molecular N-H?N hydrogen bond between them. Each nitro group is twisted out of the plane of the attached benzene ring [O-N-C-C torsion angles = 167.94?(11) and 170.38?(11)°]. In the crystal, amine-nitro N-H?O hydrogen bonds lead to centrosymmetric dimeric aggregates that are connected into a three-dimensional architecture by oxazin-yl-nitro C-H?O and ?-? inter-actions [inter-centroid distance between the oxazinyl and terminal benzene rings = 3.5069?(7)?Å].
Project description:In the mol-ecule of the title compound, C(10)H(11)NO(4), the nitro group is approximately coplanar with the benzene ring [dihedral angle = 4.57?(10)°], while the carboxyl-ate group is slightly twisted, making an angle of 12.16?(8)°. In the crystal, weak inter-molecular C-H?O hydrogen bonding and ?-? stacking inter-actions [centroid-centroid distances = 3.670?(2) and 3.665?(2)?Å] are observed.
Project description:In the title compound, C(10)H(11)N(3)O(2), the nitro group is essentially coplanar with the aromatic ring [dihedral angle = 3.4?(3)°] and forms an intra-molecular N-H?O hydrogen bond with the amine group. In the crystal, weak aromatic C-H?O and C-H?N hydrogen bonds link the mol-ecules. Weak aromatic ring ?-? inter-actions [minimum ring centroid-centroid separation = 3.9841?(16)?Å] are also present.
Project description:In the title compound, C17H11Br2N3O4, the dihedral angle between the planes of the naphthalene system and the benzene ring is 52.86?(8)°. The nitro substituent and the attached naphthalene system are almost coplanar [dihedral angle = 5.6?(4)°], probably as a consequence of an intra-molecular N-H?O hydrogen bond with the amine group. The nitro substituent attached to the benzene ring is disordered over two sets of sites with occupancies of 0.694?(3) and 0.306?(3). The major component deviates significantly from the ring plane [dihedral angle = 53.6?(2)°]. In the crystal, the mol-ecules are linked into a three-dimensional array by extensive ?-? inter-actions involving both the naphthalene and benzene rings [range of centroid-centroid distances = 3.5295?(16)-3.9629?(18)?Å] and C-H?O inter-actions involving the methyl-ene H atoms and the phenyl-attached nitro group.
Project description:In the title mol-ecule, C(12)H(15)NO(5), the nitro-phen-oxy portion is approximately planar (r.m.s. deviation = 0.034?Å) and makes an angle of 84.8?(1)° with respect to the -CH(2)-C(=O)-O-C fragment. In the crystal, ?-? stacking is observed between nearly parallel benzene rings of adjacent mol-ecules, the centroid-centroid distance being 3.6806?(10)?Å. Weak inter-molecular C-H?O hydrogen bonding is present in the crystal structure.
Project description:The title benzimidazole mol-ecule, C(8)H(8)N(4)O(2)·2H(2)O, is planar with a maximum deviation of 0.079?(2)?Å (for one of the O atoms in the nitro group). It crystallized as a dihydrate and inter-molecular O-H?O and N-H?O hydrogen bonds link the uncoordinated water mol-ecules, and the nitro and amine groups, respectively. In the crystal, N-H?O, O-H?N, O-H?O and C-H?O hydrogen bonds link the mol-ecules to form a three-dimensional network. A ?-? contact between the benzene rings, [centroid-centroid distance = 3.588?(1)?Å] may further stabilize the crystal structure.
Project description:In the structure of the title salt, [Rb2(C7H5N2O4)2(H2O)2] n , the asymmetric unit comprises two independent and different seven-coordinate Rb(+) cations, one forming an RbO7 polyhedron, the other a RbO6N polyhedron, each of which is considerably distorted. The RbO7 polyhedron comprises bridging O-atom donors from two water mol-ecules, three carboxyl-ate groups, and two nitro groups. The RbO6N polyhedron comprises the two bridging water mol-ecules, one monodentate amine N-atom donor, one carboxyl O-atom donor and three O-atom donors from nitro groups (one from the chelate bridge). The extension of the dinuclear unit gives a three-dimensional polymeric structure which is stabilized by both intra- and inter-molecular amine N-H?O and water O-H?O hydrogen bonds to carboxyl and water O-atom acceptors, as well as a number of inter-ring ?-? inter-actions [minimum centroid-centroid separation = 3.364?(2)?Å]. The title salt is isostructural with the analogous caesium salt.
Project description:In the title compound, C(13)H(12)N(4)O(6), the mean plane through the nitro-benzene forms a dihedral angle of 37.38?(15)° with the plane through the imidazole ring. The crystal packing is stabilized by weak inter-molecular C-H?O and C-H?N inter-actions together with ?-? stacking inter-actions between nitro-benzene rings [centroid-centroid distance = 3.788?(3)?Å] and between imidazole rings [centroid-centroid distance = 3.590?(2)?Å].