5-(2-Chlorophenyl)-3-(4-chlorophenyl)-1-phenyl-2-pyrazoline

Abstract

In the title structure, C21H16Cl2N2, the pyrazoline ring makes dihedral angles of 6.76 (9), 7.52 (10) and 81.88 (10)°, respectively, with the 4‐chloro­phenyl ring, the phenyl ring and the 2‐chlorophenyl ring. The 5‐phenyl ring is almost perpendicular to the pyrazoline ring.

Comparative study on two 2-pyrazoline derivatives with experimental and theoretical methods

“…The bond length of C(7)-N(2) in 2 is 1.477(3) Å , which is comparable to the C-N bond length of 1.474(2) Å in 1. The N-N bond length in 2 is 1.383(3) Å , which is also in agreement with the N-N bond length of 1.380(2) Å in 1 [22]. The C-Cl bond length [1.740(3) Å ] in 2 is shorter than both of the C-Cl bond lengths in 1 [C-Cl 1.750(1) and 1.751(2) Å ] [22].…”

“…The N-N bond length in 2 is 1.383(3) Å , which is also in agreement with the N-N bond length of 1.380(2) Å in 1 [22]. The C-Cl bond length [1.740(3) Å ] in 2 is shorter than both of the C-Cl bond lengths in 1 [C-Cl 1.750(1) and 1.751(2) Å ] [22]. In 2, the pyrazoline ring makes dihedral angles of 8.02(10), 22.46(11) and 67.67 (11), respectively, with the p-methylphenyl, phenyl and 2-chlorophenyl rings.…”

“…All of the bond lengths and bond angles in the phenyl rings are in the normal range. In the pyrazolinyl ring of the molecule 2, the C(9)=N(1) bond length of 1.289(3) Å is slightly shorter than the C=N bond length of 1.297(2) Å in the similar structure of 1 [22]. The bond length of C(7)-N(2) in 2 is 1.477(3) Å , which is comparable to the C-N bond length of 1.474(2) Å in 1.…”

“…Although the crystal structure of 1 has been reported in 2007 [22], to the best of our knowledge, there is no further investigation on it available till now by both experimental and theoretical methods. Also, there are no comparative studies about compounds of 1 and 2.…”

“…Many 1,3,5-triaryl-2-pyrazolines have been reported as hole transporting or emitting materials in organic EL devices [14][15][16][17]. Our group recently have focused our attentions on investigating 1,3,5-triaryl-2-pyrazolines [18][19][20][21][22]. 1-Phenyl-3-(4-chlorophenyl)-5-(2-chlorophenyl)-2-pyrazoline (1) and…”