A new polymorph of 1-ferrocenyl-3-(3-nitroanilino)propan-1-one

Abstract

Recrystallization of the title compound, [Fe(C(5)H(5))(C(14)H(13)N(2)O(3))], from a mixture of n-hexane and dichloromethane gave the new polymorph, denoted (I), which crystallizes in the same space group (P1) as the previously reported structure, denoted (II). The Fe-C distances in (I) range from 2.015 (3) to 2.048 (2) Å and the average value of the C-C bond lengths in the two cyclopentadienyl (Cp) rings is 1.403 (13) Å. As indicated by the smallest C-Cg1-Cg2-C torsion angle of 1.4° (Cg1 and Cg2 are the centroids of the two Cp rings), the orientation of the Cp rings in (I) is more eclipsed than in the case of (II), for which the value was 15.3°. Despite the pronounced conformational similarity between (I) and (II), the formation of self-complementary N-H···O hydrogen-bonded dimers represents the only structural motif common to the two polymorphs. In the extended structure, molecules of (I) utilize C-H···O hydrogen bonds and, unlike (II), an extensive set of intermolecular C-H···π interactions. Fingerprint plots based on Hirshfeld surfaces are used to compare the packing of the two polymorphs.

3-Anilino-1-ferrocenylpropan-1-one

“…For the physico-chemical properties of ferrocene-based compounds, see: Togni & Hayashi (1995). For related crystal structures and details of the synthesis, see: Damljanović et al (2011); Stevanović et al (2012); Leka, Novaković, Stevanović et al (2012); Leka, Novaković, Pejović et al (2012).…”

1-Ferrocenyl-3-(4-methylanilino)propan-1-one

“…The torsion angle O1-C11-C1-C5 which relates Cp1 ring with the carbonyl group is here equal to -6.2 (3)°, showing the expected co-planarity. Although C1-C11-C12-C13-N1 fragment consists of single bonds which allows for free rotation, the molecule adopts a conformation very similar to the previously reported derivatives (Damljanović et al, 2011;Stevanović et al, 2012). The bent conformation of the molecule is indicated by the C11-C12-C13-N1 torsion angle [(70.6 (3)°] which is slightly smaller than in the case of the molecule containing unmodified, phenylamino moiety.…”

“…For the physico-chemical properties of ferrocene-based compounds, see: Togni & Hayashi (1995). For related crystal structures and details of the synthesis, see: Damljanović et al (2011); Stevanović et al (2012); Leka et al (2012a,b).…”

3-(3-Acetylanilino)-1-ferrocenylpropan-1-one

“…For related structures and details of the synthesis, see: Damljanović et al (2011); Pejović et al (2012); Stevanović et al (2012); Leka et al (2012a,b,c).…”