N¹,N⁴-Diethynyl-N¹,N⁴-diphenylbenzene-1,4-diamine

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.