4-Di-phenyl-phosphanyl-8-methyl-1,5-naphthyridine

Area of Science:

• Crystallography
• Organic Chemistry
• Materials Science

Background:

• Understanding the three-dimensional arrangement of atoms in organic molecules is crucial for predicting their properties.
• Aromatic ring orientation significantly influences molecular packing and intermolecular interactions.
• 1,5-naphthyridine derivatives are of interest due to their diverse applications.

Purpose of the Study:

• To elucidate the crystal structure of the title compound, C21H17N2P.
• To quantify the dihedral angles between the 1,5-naphthyridine core and its phenyl substituents.
• To investigate potential intermolecular interactions within the crystal lattice.

Main Methods:

• Single-crystal X-ray diffraction analysis was employed to determine the molecular structure.
• Geometric parameters, including dihedral angles and bond lengths/angles, were precisely measured.
• Intermolecular distances were analyzed to identify weak interactions.

Main Results:

• The 1,5-naphthyridine ring system exhibits a planar conformation (r.m.s. deviation = 0.005 Å).
• Phenyl rings are oriented at significant dihedral angles relative to the naphthyridine core (89.18(8)° and 77.39(8)°).
• The phenyl rings themselves are nearly perpendicular to each other (dihedral angle = 88.12(8)°).
• A weak, intermolecular aromatic π-π stacking interaction was identified with a centroid-centroid separation of 3.898(2) Å.

Conclusions:

• The crystal structure of C21H17N2P is characterized by highly non-planar arrangements of its aromatic systems.
• The observed molecular geometry suggests limited electronic communication between the aromatic moieties in the solid state.
• The weak π-π stacking interaction is the primary intermolecular force, influencing crystal packing.