4-Methyl-3-nitroaniline

• CAS: 119-32​-4
• Catalog Number: ACM119324
• Category: Main Products
• Molecular Weight: 152.15
• Molecular Formula: C₇H₈N₂O₂
• Appearance: powder

Case Study

4-Methyl-3-Nitroaniline Used in the Synthesis of Propellant Stabilizers

Lundell, Carl E., et al. Chemistryselect, 2017, 2(35), 11673-11676.

Complexes of lead(II) ions with nitroaromatic amines, including 4-methyl-3-nitroaniline and 2-nitrodiphenylamine (NDPA), were prepared to develop alternative ballistic modifiers. The results show that the energy densities of tetrakis(μ3-(4-methyl-3-nitrophenyl imido lead (II))) 1 and bis(2-nitrodiphenyl amido lead(II)) 2 are 30 MJ/L and 38.2 MJ/L, respectively.
Synthesis & structure of tetrakis(μ3-(4-methyl-3-nitrophenyl imido lead (II)))
· The reaction between lead bis(trimethylsilyl)amide and 4-methyl-3-nitroaniline in a 1:1 stoichiometric ratio resulted in the formation of tetrakis(m-(4-methyl-3-nitrophenylimidolead(II))) (1) through the protolysis of hexamethyldisilazane by the acidic amine protons. The initial 1:1 complex further tetramerized into a cubane cluster 1.
· Analysis using X-ray crystallography of the dark red/rust colored crystals showed a distorted cubane structure where Pb and N atoms occupied the corner positions of the cube. The acute interior N-Pb-N angles were around 78° and the interior Pb-N-Pb angles were approximately 101°. The lead corners were protruding and acute, without any observed interaction with a capping ligand. The lead atoms exhibited weak interactions with the tetrahydrofuran (THF) solvent and neighboring nitro groups.

4-Methyl-3-Nitroaniline for the Synthesis of New Amides of N-Methylpiperazine Series

Koroleva, E. V., et al. Russian Journal of Organic Chemistry, 2011, 47, 1556-1563.

The diversity of pharmacological properties and selectivity of biological actions indicate the strong potential of compounds containing benzylpiperazine or piperazine carboxamide fragments. This work synthesizes new functionalized amides based on benzylpiperazine derivatives and substituted benzoic acids, which involves the conversion of 4-methyl-3-nitroaniline (IX) into N-(4-methyl-3-nitrophenyl)-4-(4-methylpiperazin-1-ylmethyl)benzamide (X).
Synthesis procedures compound X from 4-methyl-3-nitroaniline
· Triethylamine (0.6 g, 6 mmol) was introduced with stirring at room temperature to a solution of 4-methyl-3-nitroaniline (IX) (0.5 g, 3 mmol) in 10 ml of THF.
· The temperature of the solution was lowered to 0°C before adding 1.15 g (3.5 mmol) of dihydrochloride VII [4-(4-Methylpiperazin-1-ylmethyl)benzoyl chloride dihydrochloride]. The resulting mixture was stirred at 0°C for 1 hour and then at 50°C for 16 hours.
· After evaporating the mixture, the residue was treated with 10 ml of 10% aqueous sodium hydroxide and extracted with ethyl acetate (3x20 ml). The ethyl acetate extract was dried with Na2SO4, then evaporated under reduced pressure. The remaining substance was purified through recrystallization from chloroform-diethyl ether, yielding 48%.

Supramolecular Structure and Hydrogen Bonding of 4-Methyl-3-nitroaniline

Cannon, D., et al. Acta Crystallographica Section C 57.2 (2001): 216-221

This study investigated the supramolecular structure and hydrogen bonding interactions of 4-methyl-3-nitroaniline (C₇H₈N₂O₂, III) using single-crystal X-ray diffraction. The compound crystallizes with Z'=4 (four molecules per asymmetric unit) and forms a one-dimensional supramolecular structure, distinct from the three-dimensional framework of its isomer 2-methyl-4-nitroaniline and two-dimensional sheets of unsubstituted 4-nitroaniline. Key geometric parameters show that the C-NH₂ bond lengths range from 1.370(2) to 1.380(2) Å (mean 1.376(2) Å), significantly longer than those in 2-methyl-4-nitroaniline (1.358(2) Å), while C-NO₂ bond lengths are 1.465(2)-1.469(2) Å (mean 1.467(2) Å), much longer than analogous bonds in isomeric methylnitroanilines. The supramolecular aggregation involves N-H···O hydrogen bonds, forming both simple chains and molecular ladders, with no aromatic π-π stacking interactions. These studies demonstrate that the position of the methyl substituent in C-methylated nitroanilines drastically influences supramolecular dimensionality, with 4-methyl-3-nitroaniline adopting a one-dimensional structure via specific hydrogen bonding motifs.
The in vitro single-crystal analysis of 4-methyl-3-nitroaniline was conducted through controlled experiments. Crystals suitable for X-ray diffraction were grown from ethanol solution, and data were collected using a diffractometer with Mo Kα radiation at 150(2) K. Structure solution and refinement were performed using SHELXS97 and SHELXL97 programs, with H-atom parameters constrained (N-H=0.86 Å, C-H=0.93 Å for aromatic, 0.96 Å for methyl). Hydrogen bonding geometry was analyzed using PLATON software, confirming N-H···O interactions as the primary supramolecular linkers. Unit cell parameters and space group were determined from 1316 independent reflections, with refinement on F² yielding R[F²>2σ(F²)]=0.043 and wR(F²)=0.113. Comparisons with isomeric compounds (2-methyl-4-nitroaniline, 4-methyl-2-nitroaniline) were made to elucidate the effect of substituent position on molecular packing and hydrogen bonding patterns.

Polymorphism and Supramolecular Structure of 4-Methyl-3-nitroaniline

Zakaria, Choudhury M., et al. Acta Crystallographica Section C 57.11 (2001): 1207-1208

This study investigated the polymorphism and supramolecular structure of 4-methyl-3-nitroaniline (C₇H₈N₂O₂) using single-crystal X-ray diffraction, identifying two polymorphs with distinct crystal structures. At ambient temperature (295 K), it crystallizes in the monoclinic space group P2₁/n with Z'=2 (two independent molecules per asymmetric unit) and unit cell parameters a=8.2473(7) Å, b=7.5676(7) Å, c=23.7798(16) Å, β=91.717(5)°. Each molecule acts as a single donor and acceptor in N-H···O hydrogen bonds, forming two independent C(7) chains parallel to the [100] direction (no interchain hydrogen bonds or π-π stacking). At low temperature (150 K), it adopts a triclinic P1 structure with Z'=4, where two molecule types form chains and the other two form molecular ladders. The monoclinic and triclinic polymorphs are related by a displacive phase transformation, with consistent nitro-group twist angles (7.5-32.5°) mapping between corresponding molecules. These studies demonstrate that 4-methyl-3-nitroaniline exhibits temperature-dependent polymorphism, with supramolecular aggregation governed by N-H···O hydrogen bonds and distinct chain/ladder motifs across polymorphs.The in vitro single-crystal analysis of 4-methyl-3-nitroaniline was conducted through controlled experiments. Crystals of the monoclinic polymorph were grown from ethanol and CH₂Cl₂ solutions, while the triclinic polymorph was obtained from ethanol at low temperature. X-ray diffraction data were collected using a KappaCCD diffractometer (monoclinic) and Bruker SMART 1000 CCD diffractometer (triclinic), with Mo Kα radiation. Structure solution and refinement were performed via SHELXS97 and SHELXL97, with H-atom parameters constrained (N-H=0.86 Å, C-H=0.93 Å for aromatic, 0.96 Å for methyl). Hydrogen bonding geometry was analyzed using PLATON software, confirming N-H···O interactions (D···A=3.181-3.285 Å, D-H···A=150-163°) as the primary supramolecular linkers. Unit cell transformations and atomic coordinate mappings verified the displacive relationship between polymorphs, with refinement statistics R[F²>2σ(F²)]=0.061 (monoclinic) and 0.043 (triclinic).