3-Acetyl-6-chloro-2-methyl-4-phenylquinolinium hydrogen sulfate

In the title salt, C18H15ClNO+·HSO4 −, the quinolinium ring system is approximately planar, with a maximum deviation of 0.028 (2) Å, and forms a dihedral angle of 78.43 (4)° with the attached phenyl ring. A pair of intermolecular O—H⋯O hydrogen bonds links two hydrogen sulfate anions into a dimer, generating a R 2 2(8) ring motif. Intermolecular N—H⋯O hydrogen bonds and C—H⋯O contacts link the ions into a three-dimensional network. The structure is further stabilized by C—H⋯π interactions

In the title salt, C 18 H 15 ClNO + ÁHSO 4 À , the quinolinium ring system is approximately planar, with a maximum deviation of 0.028 (2) Å , and forms a dihedral angle of 78.43 (4) with the attached phenyl ring. A pair of intermolecular O-HÁ Á ÁO hydrogen bonds links two hydrogen sulfate anions into a dimer, generating a R 2 2 (8) ring motif. Intermolecular N-HÁ Á ÁO hydrogen bonds and C-HÁ Á ÁO contacts link the ions into a three-dimensional network. The structure is further stabilized by C-HÁ Á Á interactions

Comment
Quinolines and their derivatives are very important compounds because of their wide occurrence in natural products (Morimoto et al., 1991;Michael, 1997) and biologically active compounds (Markees et al., 1970;Campbell et al., 1988). A large variety of quinolines have interesting physiological activities and have found attractive applications as pharmaceuticals, agrochemicals and as synthetic building blocks (Maguire et al., 1994;Kalluraya & Sreenivasa, 1998;Roma et al., 2000;Chen et al., 2001). The 3-acetyl-6-chloro-2-methyl-4-phenylquinoline has been synthesized using the method available in the literature (Fun et al., 2009), and then converted into the title salt, (I).
The asymmetric unit of (I), Fig. 1, contains a 3-acetyl-6-chloro-2-methyl-4-phenylquinolinium cation and a hydrogen sulfate anion. One proton is transferred from the hydroxyl group of hydrogen sulfate to the atom N1 of 3-acetyl-6-chloro-2methyl-4-phenylquinoline during crystallisation resulting in the formation of salt, (I). The quinolinium ring system (C1-C9/ N1) is approximately planar with a maximum deviation of 0.028 (2) Å at atom C7. This mean plane of the quinolinium ring forms a dihedral angle of 78.43 (4)° with the phenyl ring (C10-C15). Bond lengths and angles are comparable to a closely related structure (Fun et al., 2009).

Experimental
To a solution of 3-acetyl-6-chloro-2-methyl-4-phenylquinoline (10 ml, 1 M) in ethanol, copper sulfate solution (1 ml, 1 M) and concentrated H 2 SO 4 (1 ml) was added and then refluxed for about 10 min. The contents were filtered and kept for 92 h for crystallization.

Refinement
All hydrogen atoms were located from the difference Fourier map and were refined freely (range of C-H = 0.91 (3) -0.96 (3) Å and see Table 1).