Benzyl 5-ferrocenyl-3-(4-methylphenyl)-2-pyrazoline-1-dithiocarboxylate

In the title compound, [Fe(C5H5)(C23H21N2S2)], the cyclopentadienyl rings of the ferrocenyl unit deviate slightly from the eclipsed form. In the pyrazoline ring, the N atom bonded to S-benzyl dithiocarbazate exhibits unconventional sp 2-hybrid character in order to form an extended conjugated system. The pyrazoline ring displays an envelope conformation. The molecules are linked into chains along the b axis via C—H⋯S intermolecular hydrogen bonds.

In the title compound, [Fe(C 5 H 5 )(C 23 H 21 N 2 S 2 )], the cyclopentadienyl rings of the ferrocenyl unit deviate slightly from the eclipsed form. In the pyrazoline ring, the N atom bonded to S-benzyl dithiocarbazate exhibits unconventional sp 2hybrid character in order to form an extended conjugated system. The pyrazoline ring displays an envelope conformation. The molecules are linked into chains along the b axis via C-HÁ Á ÁS intermolecular hydrogen bonds.
tensively applied in the industry due to the high fluorescence quantum yield (Wilkinson et al., 1990;Rivett et al., 1979).
For example, pyrazolines have been widely used as optical brightening agents for textiles, paper and fabrics and as a holeconveying medium in photoconductive materials (Sun et al., 2004;Huang & Katzenellenbogen, 2000;Wiley et al., 1958).
We found that ferrocene derivatives have good properties of fluorescence and coordination chemistry with many metal ions (Huang et al., 1998;Shi et al., 2004). Continuing our research (Liu et al., 2007) we report the synthesis and structure of the title compound, (I).
In the structure of (I), the substituted ring (Cps) and unsubstituted ring (Cp) of the ferrocenyl moiety are slightly deprived from eclipsed form, with the five pseudo-torsion angles in the range 10.5 (2) -10.9 (3)°. The distances from central Fe (II) ion to Cps center [Cg(1)] and to Cp center [Cg(2)] are 1.651 (3) Å and 1.656 (2) Å, respectively. The angle Cg(1)-Fe-Cg (2) is 177.9 (3)° and the central Fe(II) ion is located almost in the middle of the two cyclopentadiene rings which are not parallel because their dihedral angle is 2.3 (4)° (Fig. 1).
In the pyrazolinyl ring, the C=N and C-N bond lengths are in agreement with those found in similar structures (Fahrni et al., 2003). However, the N-N bond length is longer than those found in the above-cited structures. But the bond distance of C21-N1 is shorter than a C-N single bond and slight longer than a C=N double bond. It might contribute to unclassical sp 2 -hybrid N1 atom which is evident from the sum of the three angles around the N1 atom being 360° (Table 1) and that atoms C21, N1, N2 and C13 are co-planar. Furthemore, atoms S2, C21, N1, N2, C13 along with adjacent phenyl ring result in a large cojugated system.
supplementary materials sup-2 Refinement All H atoms were fixed geometrically at ideal positions and allowed to ride on the parent atoms with C-H distances 0.96, 0.97, 0.98 and 0.93 Å for CH 3 , CH 2 , CH and aromatic CH groups, respectively, and with U iso (H) values of 1.2 and 1.5 times U eq (C) for the nonmethyl and methyl groups, respectively. Fig. 1. The molecular structure of (I); displacement ellipsoids are drawn at 50% probability level. Benzyl 5-ferrocenyl-3-(4-methylphenyl)-2-pyrazoline-1-dithiocarboxylate  Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.