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Updated: May 26, 2026

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid
Published on: November 15, 2017
N,N-Diethynyl-N,N-diphenyl-benzene-1,4-diamine
Hideyuki Tabata1, Tsunehisa Okuno
1Department of Material Science and Chemistry, Wakayama University, Sakaedani, Wakayama 640-8510, Japan.
Abstract:
The title compound, C(22)H(16)N(2), is the first example of an ynamine with H atoms bonded to the terminal C atoms. The environment around each N atom is almost planar. The distances of the N atoms from a least squares plane fitted through each N atom and the surrounding three C atoms, are 0.087 (3) and 0.041 (4) Å. The dihedral angles between these two planes and the central phenyl-ene ring are 23.34 (14) and 34.57 (14)°. The two acetyl-ene groups have an anti conformation, keeping a conjugation through the central benzene ring. The freely refined lengths of C(sp)-H are 1.00 (5) and 0.93 (4) Å, consistent with those of reported acetyl-enes. The H atoms bound to terminal C atoms have short contacts with the neighboring acetyl-enic C and N atoms. The closest contacts are an H⋯N distance of 2.67 (5) Å and an H⋯C distance of 2.74 (5) Å.
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