1-Butyl-4-hydroxy-3-methylquinoline-2(1H)-one

In the crystal of the title compound, C14H17NO2, molecules are arranged into chains along the b axis linked via O—H⋯O hydrogen bonds. While the benzene ring is essentially planar, with a maximum deviation from the best plane of 0.003 (1) Å, the pyridine ring is slightly V-shaped: the distance of the carbonyl C atom from the benzene best plane is 0.120 (1) Å. The hydroxy group is inclined markedly towards the benzene ring reducing the C—C—O bond angle to 113.21 (10)°.

In the crystal of the title compound, C 14 H 17 NO 2 , molecules are arranged into chains along the b axis linked via O-HÁ Á ÁO hydrogen bonds. While the benzene ring is essentially planar, with a maximum deviation from the best plane of 0.003 (1) Å , the pyridine ring is slightly V-shaped: the distance of the carbonyl C atom from the benzene best plane is 0.120 (1) Å . The hydroxy group is inclined markedly towards the benzene ring reducing the C-C-O bond angle to 113.21 (10) .

Related literature
For the preparation, see: Stadlbauer & Kappe (1985). The title compound is a member of a group of substituted 4-hydroxyquinoline-2-ones used for preparation of new classes of heterocyclic systems, see: Klá sek et al. (1998); Kafka et al. (2002).
Financial support of this work by the internal grant of TBU in Zlín No. IGA/7/FT/10/D, funded from the resources of specific university research, is gratefully acknowledged. 1-Butyl-4-hydroxy-3-methylquinoline-2(1H)-one Z. Kozubková, M. Necas and R. Vícha Comment Quinoline derivatives are well known and extensively studied especially for their wide occurance in nature and for their rich spectrum of biological activities. The title compound is a member of the group of substituted 4-hydroxyquinoline-2-ones used for preparation of new classes of heterocyclic systems (Klásek et al., 1998;Kafka et al., 2002).
The geometry around C3 markedly differs from the ideal pattern for a sp 2 carbon. All involved atoms C4-C2 and O1 lie in the plane of the phenyl ring (maximum deviation from the best plane is 0.0083 (12)Å for C3) but the valence angles C4-C3-O1 and C2-C3-O1 are 113.21 (10) Table 1) into chains parallel to the b-axis.

Experimental
Title compound was prepared according to a slightly modified procedure published by Stadlbauer & Kappe (1985). A mixture of N-butylaniline (16 cm 3 , 0.1 mol) and diethyl methylmalonate (17.2 cm 3 , 0.1 mol) was gradually heated in a Wood's metal bath at 413-553K for 6 h. The reaction was stopped when the amount of condensed ethanol reaches about 93% of the theoretical value. The hot mixture was poured on a metal plate and the crude product was quantitatively transferred into a 500 cm 3 Erlenmeyer flask. After addition of 300 cm 3 of 0.5 M NaOH and 50 cm 3 of toluene the resulting mixture was stirred for 1 h. The suspension was extracted twice with 40 cm 3 of toluene and the collected organic portions were treated with powdered activated carbon for 30 min at room temperature. The activated carbon was filtered off and approximately 300-400 cm 3 of 5% HCl was added gradually into the filtrate. The precipitated crude product were filtered with suction and washed with water until neutral pH. Single crystals for X-ray analysis were grown by spontaneous evaporation from deuterochloroform at room temperature.

Refinement
Hydrogen atoms were positioned geometrically and refined as riding using standard SHELXL-97 facilities, with their U iso set to either 1.2U eq or 1.5U eq (methyl) of their parent atoms.
supplementary materials sup-2 Figures   Fig. 1. Anisotropic displacement view of the asymmetric unit with atoms represented as 50% probability ellipsoids.  as those based on F, and R-factors based on ALL data will be even larger.