1-Methyl-2-(4-methyl­phen­yl)-4-morpholinopyridazine-3,6(1H,2H)-dione

Andrzej Gzella; Ewa Melzer; Michał S Kaczmarek; Zenon Woźniak

doi:10.1107/S1600536808000111

. 2008 Jan 11;64(Pt 2):o435. doi: 10.1107/S1600536808000111

1-Methyl-2-(4-methylphenyl)-4-morpholinopyridazine-3,6(1H,2H)-dione

Andrzej Gzella ^a,^*, Ewa Melzer ^a, Michał S Kaczmarek ^b, Zenon Woźniak ^b

PMCID: PMC2960232 PMID: 21201462

Abstract

The structure analysis of the title compound, C₁₆H₁₉N₃O₃, has been undertaken in order to facilitate the interpretation of ¹H and ¹³C NMR data and to determine the position of the morpholine residue in this nucleophilic substitution product. The main result is that the morpholine group, with a chair conformation, is connected at the 4-position of the pyridazine ring. The benzene and pyridazine rings make a dihedral angle of 62.17 (5)°. Molecules are linked into a two-dimensional network by non-classical C—H⋯O hydrogen bonds, in which O atoms serve as double or triple acceptors.

Related literature

For related literature, see: Allen et al. (1987 ▶); Bałoniak & Melzer (1979 ▶); Katrusiak et al. (2002 ▶).

Experimental

Crystal data

C₁₆H₁₉N₃O₃
M _r = 301.34
Monoclinic,
a = 5.6246 (6) Å
b = 8.8923 (6) Å
c = 15.0842 (10) Å
β = 99.530 (7)°
V = 744.03 (11) Å³
Z = 2
Cu Kα radiation
μ = 0.78 mm⁻¹
T = 293 (2) K
0.38 × 0.35 × 0.30 mm

Data collection

Kuma Diffraction KM-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.716, T _max = 0.794
2796 measured reflections
2705 independent reflections
2646 reflections with I > 2σ(I)
R _int = 0.025
2 standard reflections every 100 reflections intensity decay: <2%

Refinement

R[F ² > 2σ(F ²)] = 0.029
wR(F ²) = 0.082
S = 1.06
2705 reflections
202 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.13 e Å⁻³
Absolute structure: Flack (1983 ▶); 1249 Friedel pairs
Flack parameter: 0.07 (16)

Data collection: KM-4 Software (Kuma, 1996 ▶); cell refinement: KM-4 Software; data reduction: KM-4 Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808000111/cf2177sup1.cif

e-64-0o435-sup1.cif^{(19.5KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808000111/cf2177Isup2.hkl

e-64-0o435-Isup2.hkl^{(130.1KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C17—H17A⋯O15	0.97	2.21	2.8636 (18)	124
C10—H10⋯O15ⁱ	0.93	2.53	3.3508 (19)	148
C14—H14C⋯O15ⁱ	0.96	2.53	3.419 (2)	155
C5—H5⋯O19ⁱⁱ	0.93	2.49	3.4124 (19)	174
C21—H21B⋯O19ⁱⁱ	0.97	2.52	3.3036 (18)	137

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Symmetry codes: (i) Inline graphic ; (ii) .

supplementary crystallographic information

Comment

Treatment of 4-bromo-1-methyl-2-(4-methylphenyl)-3,6-pyridazinedione with morpholine in anhydrous ethanol gives a mixture of ipso and cine substitution products; one of them, labelled as (I), was found as a precipitate (Bałoniak & Melzer, 1979). The crystal structure determination of (I) was carried out in order to facilitate the interpretation of ¹H and ¹³C NMR data, to determine the position of the morpholine residue on the pyridazinedione ring, and to study the nature of the hydrogen-bond formation in the crystalline state.

The X-ray analysis revealed the molecular structure of (I) and its conformation and distortions induced in the pyridazine ring by substituents.

The geometry of the molecule of (I) is illustrated in Fig. 1. The pyridazine ring is nearly planar with an r.m.s. deviation of 0.0211 Å. The methyl, p-methylphenyl and morpholine substituents are connected at N1, N2 and C4, respectively. The mean plane of the benzene ring is oriented at an angle of 62.17 (5)° to the mean plane of the pyridazine ring. The C4—C5 bond, 1.3500 (18) Å, belonging to the latter ring, is a double bond.

The ring bonds are conjugated, and the formally single bond C5—C6 is shorter by about 14 and the bond C3—C4 is longer by about 13σ than the normal (C?)Csp²—Csp²(?O) single bond [1.465 (1) Å; Allen et al., 1987]. The elongation of the latter is a result of the presence of the morpholine residue at C4. The last two observations are consistent with that reported for 2-methyl-4-morpholino-1-phenyl-3,6-pyridazinedione (Katrusiak et al., 2002).

The C3—N1 and C6—N1 distances are similar [1.3700 (18) and 1.3686 (17) Å, respectively] and are somewhat larger than a normal C—N tertiary amide distance [1.346 (5) Å; Allen et al., 1987]. The sums of valency angles around N1 and N2 atoms are 356.5 and 357.4°. Atom C7 of the methyl group has a mutual orientation of synperiplanar and synclinal with respect to the atom C8 of the benzene ring [torsion angle C7—N1—N2—C8 = -37.79 (18)°].

The molecules in the crystal structure of (I) are linked via non-classical C—H···O hydrogen bonds (Table 1), forming a two-dimensional hydrogen-bond network parallel to the (101) plane (Figs. 2 and 3).

Experimental

Compound (I) was synthesized according to a literature procedure of Bałoniak & Melzer (1979). Crystals suitable for single-crystal X-ray diffraction analysis were grown from ethanol by slow evaporation.