2,2-Dimethyl-N-(4-methyl­pyridin-2-yl)propanamide

El-Hiti, G.A.; Smith, K.; Balakit, A.A.; Hegazy, A.S.; Kariuki, B.M.

doi:10.1107/S1600536814003729

organic compounds

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Volume 70| Part 3| March 2014| Pages o351-o352

doi:10.1107/S1600536814003729

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2,2-Dimethyl-N-(4-methylpyridin-2-yl)propanamide

Gamal A. El-Hiti,^a ^* Keith Smith,^b Asim A. Balakit,^c Amany S. Hegazy ^b and Benson M. Kariuki ^b ^*

^aDepartment of Optometry, College of Applied Medical Sciences, King Saud University, PO Box 10219, Riyadh 11433, Saudi Arabia, ^bSchool of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Wales, and ^cDepartment of Chemistry, College of Science for Women, University of Babylon, Babylon, Iraq
^*Correspondence e-mail: gelhiti@ksu.edu.sa, kariukib@cardiff.ac.uk

(Received 6 February 2014; accepted 18 February 2014; online 26 February 2014)

In the title compound, C₁₁H₁₆N₂O, the dihedral angle between the mean plane of the 4-methypyridine group and the plane of the amide link is 16.7 (1)°, and there is a short intramolecular C—H⋯O contact. Hydrogen bonding (N—H⋯O) between amide groups forms chains parallel to the b axis. Pairs of methylpyridine groups from molecules in adjacent chains are parallel but there is minimal π–π interaction.

CCDC reference: 987696

Related literature

For biological applications of related compounds, see: de Candia et al. (2013 ); Thorat et al. (2013 ); Abdel-Megeed et al. (2012 ). For convenient routes for modifying pyridine derivatives, see: Smith et al. (2013 ); Smith et al. (2012 ); El-Hiti (2003 ); Joule & Mills (2000 ); Smith et al. (1994 , 1995 , 1999 ); Turner (1983 ). For the X-ray structures of related compounds, see: Mazik & Sicking (2004 ); Mazik et al. (2004 ); Hodorowicz et al. (2007 ); Koch et al. (2008 ); Liang et al. (2008 ); Seidler et al. (2011 ).

Experimental

Crystal data

C₁₁H₁₆N₂O
M_r = 192.26
Orthorhombic, P b c a
a = 10.7954 (3) Å
b = 10.1809 (2) Å
c = 20.8390 (5) Å
V = 2290.35 (10) Å³
Z = 8
Cu Kα radiation
μ = 0.58 mm⁻¹
T = 296 K
0.27 × 0.19 × 0.14 mm

Data collection

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014 ) T_min = 0.930, T_max = 0.957
5219 measured reflections
2253 independent reflections
1808 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.154
S = 1.08
2253 reflections
132 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O1ⁱ	0.86	2.22	3.0644 (17)	168
C5—H5⋯O1	0.93	2.28	2.842 (2)	118
Symmetry code: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: WinGX (Farrugia, 2012) and CHEMDRAW Ultra (CambridgeSoft, 2001 ).

Supporting information

CCDC reference: 987696

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536814003729/mw2120sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814003729/mw2120Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814003729/mw2120Isup3.cml

checkCIF report

Structural commentary top

Synthetic and naturally occurring pyridine derivatives have a broad range of biological activities (Thorat et al., 2013) including anticancer and antimicrobial (Abdel-Megeed et al., 2012) and anticoagulant (de Candia et al., 2013) properties. Hence, pyridine derivatives are important compounds (Joule and Mills, 2000) and some synthetic approaches involve lithiation of 2-acylaminopyridines (Smith et al., 1995; Turner, 1983). The structures of a number of 2-acylaminopyridines have been determined (Mazik & Sicking, 2004; Mazik et al., 2004; Hodorowicz et al., 2007; Koch et al., 2008; Liang et al., 2008; Seidler et al., 2011). During research focused on new synthetic routes towards novel substituted pyridine derivatives (Smith et al., 1994; Smith et al., 1995; Smith et al., 1999; El-Hiti, 2003; Smith et al., 2012; Smith et al., 2013) we have synthesized the title compound in high yield. In the 4-methyl-2-pivaloylaminopyridine molecule (Figure 1), the least squares plane through the 4-methypyridine group makes a dihedral angle of 16.7 (1)° with the plane through the amide link and a short intramolecular C5—H5···O1 contact is observed (Table 1). In the crystal structure (Figure 2) N—H···O hydrogen bonding between amide groups forms chains parallel to the b axis. Pairs of methyl-pyridine groups in molecules from adjacent chains are parallel but there is minimal π-π interaction. The ring nitrogen is not involved in strong hydrogen bonding.

Synthesis and crystallization top

To a cooled solution (0 °C) of 2-amino-4-methylpyridine (5.41 g, 50.0 mmol) and triethylamine (10 ml) in dichloromethane (DCM, 80 ml) pivaloyl chloride (6.63 g, 55.0 mmol) was slowly added in a drop-wise manner over 10 min. The reaction mixture was stirred at 0 °C for an extra 1 h. The mixture was poured into H₂O (100 ml) and the organic layer was separated, washed with H₂O (2 × 50 ml), dried (MgSO₄) and evaporated under reduced pressure to remove the solvent. The solid obtained was purified by crystallization from Et₂O–hexane (2:1) to give 4-methyl-2-pivaloylaminopyridine (9.04 g, 47.0 mmol; 94%) as colourless crystals, m.p. 103–104 °C [lit. 96–98 °C (hexane); Turner (1983)]. ¹H NMR (500 MHz, CDCl₃, δ, p.p.m.) 8.11–8.10 (br, 2 H, H-3 and H-6), 8.05 (br, exch., 1 H, NH), 6.85 (m, 1 H, H-5), 2.34 (s, 3 H, CH₃), 1.31 [s, 9 H, C(CH₃)₃]. ¹³CNMR (125 MHz, CDCl₃, δ, p.p.m.) 177.2 (s, C=O), 151.5 (s, C-4), 149.9 (s, C-2), 147.2 (d, C-6), 120.9 (d, C-5), 114.5 (d, C-3), 39.8 [s, C(CH₃)₃], 27.5 [q, C(CH₃)₃]), 21.4 (q, CH₃). EI⁺–MS (m/z, %): 192 (M⁺, 43), 177 (5), 149 (11), 135 (25), 108 (100), 92 (15), 81 (15), 57 (25). HRMS (EI⁺): Calculated for C₁₁H₁₆N₂O [M] 192.1263; found, 192.1260.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1. H atoms were positioned geometrically and refined using a riding model with U_iso(H) = 1.2 times U_eq for the atom they are bonded to except for the methyl groups where 1.5 times U_eq was used with free rotation about the C—C bond.

Related literature top

For biological applications of related compounds, see: de Candia et al. (2013); Thorat et al. (2013); Abdel-Megeed et al. (2012). For convenient routes for modifying pyridine derivatives, see: Smith et al. (2013); Smith et al. (2012); El-Hiti (2003); Joule & Mills (2000); Smith et al. (1994, 1995, 1999); Turner (1983). For the X-ray structures of related compounds, see: Mazik & Sicking (2004); Mazik et al. (2004); Hodorowicz et al. (2007); Koch et al. (2008); Liang et al. (2008); Seidler et al. (2011).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and CHEMDRAW Ultra (CambridgeSoft, 2001).

Figures top

	Fig. 1. A molecule showing atom labels and 50% probability displacement ellipsoids for non-H atoms.
	Fig. 2. Crystal structure packing showing NH..O hydrogen bonds as green dotted lines with the rest of the hydrogen atoms omitted for clarity.

2,2-Dimethyl-N-(4-methylpyridin-2-yl)propanamide top

Crystal data top

C₁₁H₁₆N₂O	D_x = 1.115 Mg m⁻³
M_r = 192.26	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, Pbca	Cell parameters from 1808 reflections
a = 10.7954 (3) Å	θ = 4.2–74.0°
b = 10.1809 (2) Å	µ = 0.58 mm⁻¹
c = 20.8390 (5) Å	T = 296 K
V = 2290.35 (10) Å³	Block, colourless
Z = 8	0.27 × 0.19 × 0.14 mm
F(000) = 832

Data collection top

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer	1808 reflections with I > 2σ(I)
Radiation source: sealed X-ray tube	R_int = 0.017
ω scans	θ_max = 74.0°, θ_min = 4.2°
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014)	h = −7→13
T_min = 0.930, T_max = 0.957	k = −12→8
5219 measured reflections	l = −25→20
2253 independent reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.046	w = 1/[σ²(F_o²) + (0.0734P)² + 0.4299P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.154	(Δ/σ)_max < 0.001
S = 1.08	Δρ_max = 0.16 e Å⁻³
2253 reflections	Δρ_min = −0.14 e Å⁻³
132 parameters	Extinction correction: SHELXL2013 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0037 (5)

Crystal data top

C₁₁H₁₆N₂O	V = 2290.35 (10) Å³
M_r = 192.26	Z = 8
Orthorhombic, Pbca	Cu Kα radiation
a = 10.7954 (3) Å	µ = 0.58 mm⁻¹
b = 10.1809 (2) Å	T = 296 K
c = 20.8390 (5) Å	0.27 × 0.19 × 0.14 mm

Data collection top

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer	2253 independent reflections
Absorption correction: gaussian (CrysAlis PRO; Agilent, 2014)	1808 reflections with I > 2σ(I)
T_min = 0.930, T_max = 0.957	R_int = 0.017
5219 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.154	H-atom parameters constrained
S = 1.08	Δρ_max = 0.16 e Å⁻³
2253 reflections	Δρ_min = −0.14 e Å⁻³
132 parameters

Special details top

Experimental. Absorption correction: CrysAlisPro (Agilent, 2014): Numerical absorption correction based on Gaussian integration over a multifaceted crystal model. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.90730 (14)	0.81479 (14)	0.59591 (7)	0.0489 (4)
C2	1.0228 (2)	0.6963 (2)	0.52600 (11)	0.0816 (6)
H2	1.0345	0.6201	0.5021	0.098*
C3	1.1102 (2)	0.7922 (2)	0.52141 (11)	0.0792 (6)
H3	1.1786	0.7811	0.4948	0.095*
C4	1.09637 (16)	0.90571 (19)	0.55651 (9)	0.0632 (5)
C5	0.99149 (14)	0.91744 (16)	0.59451 (8)	0.0552 (4)
H5	0.9779	0.9929	0.6186	0.066*
C6	1.1912 (2)	1.0138 (3)	0.55444 (12)	0.0922 (7)
H6A	1.2409	1.0107	0.5926	0.138*
H6B	1.1499	1.0972	0.5520	0.138*
H6C	1.2431	1.0025	0.5175	0.138*
C7	0.74226 (15)	0.91931 (14)	0.66136 (8)	0.0515 (4)
C8	0.62472 (16)	0.88824 (16)	0.69967 (9)	0.0606 (5)
C9	0.6598 (2)	0.8017 (2)	0.75696 (11)	0.0851 (7)
H9A	0.7235	0.8442	0.7815	0.128*
H9B	0.6895	0.7185	0.7418	0.128*
H9C	0.5882	0.7883	0.7835	0.128*
C10	0.5677 (2)	1.0158 (2)	0.72312 (13)	0.0997 (9)
H10A	0.6251	1.0600	0.7509	0.149*
H10B	0.4929	0.9970	0.7463	0.149*
H10C	0.5490	1.0709	0.6870	0.149*
C11	0.53133 (19)	0.8146 (3)	0.65810 (13)	0.0933 (8)
H11A	0.4578	0.7976	0.6826	0.140*
H11B	0.5668	0.7329	0.6442	0.140*
H11C	0.5107	0.8670	0.6213	0.140*
N1	0.92138 (14)	0.70437 (14)	0.56251 (8)	0.0654 (4)
N2	0.79937 (12)	0.81473 (12)	0.63366 (7)	0.0554 (4)
H2A	0.7654	0.7394	0.6400	0.067*
O1	0.78283 (12)	1.03049 (11)	0.65664 (7)	0.0699 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0475 (8)	0.0469 (8)	0.0523 (8)	0.0056 (6)	0.0003 (6)	0.0012 (6)
C2	0.0788 (13)	0.0735 (12)	0.0924 (14)	0.0131 (10)	0.0224 (11)	−0.0152 (11)
C3	0.0626 (11)	0.0889 (14)	0.0861 (13)	0.0180 (10)	0.0226 (10)	0.0029 (11)
C4	0.0481 (9)	0.0720 (11)	0.0694 (10)	0.0027 (8)	0.0020 (7)	0.0171 (9)
C5	0.0518 (9)	0.0531 (9)	0.0607 (9)	0.0001 (7)	0.0028 (7)	0.0032 (7)
C6	0.0587 (11)	0.1052 (17)	0.1126 (18)	−0.0166 (11)	0.0083 (11)	0.0244 (15)
C7	0.0533 (8)	0.0390 (7)	0.0622 (8)	0.0022 (6)	0.0061 (7)	−0.0009 (6)
C8	0.0592 (10)	0.0478 (8)	0.0749 (10)	0.0016 (7)	0.0190 (8)	−0.0021 (7)
C9	0.0969 (16)	0.0788 (13)	0.0798 (13)	0.0035 (12)	0.0275 (12)	0.0104 (10)
C10	0.1026 (17)	0.0605 (12)	0.136 (2)	0.0135 (11)	0.0640 (16)	−0.0025 (12)
C11	0.0548 (11)	0.1121 (19)	0.1129 (18)	−0.0056 (11)	0.0126 (12)	−0.0159 (15)
N1	0.0646 (9)	0.0546 (8)	0.0770 (9)	0.0056 (7)	0.0107 (7)	−0.0124 (7)
N2	0.0551 (8)	0.0401 (7)	0.0711 (8)	−0.0038 (5)	0.0153 (6)	−0.0040 (6)
O1	0.0673 (8)	0.0389 (6)	0.1034 (10)	−0.0010 (5)	0.0213 (7)	−0.0030 (6)

Geometric parameters (Å, º) top

C1—N1	1.3310 (19)	C7—N2	1.3590 (19)
C1—C5	1.385 (2)	C7—C8	1.532 (2)
C1—N2	1.406 (2)	C8—C10	1.518 (2)
C2—N1	1.336 (3)	C8—C11	1.526 (3)
C2—C3	1.361 (3)	C8—C9	1.531 (3)
C2—H2	0.9300	C9—H9A	0.9600
C3—C4	1.376 (3)	C9—H9B	0.9600
C3—H3	0.9300	C9—H9C	0.9600
C4—C5	1.387 (2)	C10—H10A	0.9600
C4—C6	1.503 (3)	C10—H10B	0.9600
C5—H5	0.9300	C10—H10C	0.9600
C6—H6A	0.9600	C11—H11A	0.9600
C6—H6B	0.9600	C11—H11B	0.9600
C6—H6C	0.9600	C11—H11C	0.9600
C7—O1	1.2177 (18)	N2—H2A	0.8600

N1—C1—C5	123.45 (15)	C11—C8—C9	108.85 (18)
N1—C1—N2	112.76 (13)	C10—C8—C7	109.09 (14)
C5—C1—N2	123.78 (14)	C11—C8—C7	110.66 (15)
N1—C2—C3	124.35 (19)	C9—C8—C7	108.69 (15)
N1—C2—H2	117.8	C8—C9—H9A	109.5
C3—C2—H2	117.8	C8—C9—H9B	109.5
C2—C3—C4	119.33 (18)	H9A—C9—H9B	109.5
C2—C3—H3	120.3	C8—C9—H9C	109.5
C4—C3—H3	120.3	H9A—C9—H9C	109.5
C3—C4—C5	117.68 (17)	H9B—C9—H9C	109.5
C3—C4—C6	121.72 (19)	C8—C10—H10A	109.5
C5—C4—C6	120.60 (19)	C8—C10—H10B	109.5
C1—C5—C4	118.87 (16)	H10A—C10—H10B	109.5
C1—C5—H5	120.6	C8—C10—H10C	109.5
C4—C5—H5	120.6	H10A—C10—H10C	109.5
C4—C6—H6A	109.5	H10B—C10—H10C	109.5
C4—C6—H6B	109.5	C8—C11—H11A	109.5
H6A—C6—H6B	109.5	C8—C11—H11B	109.5
C4—C6—H6C	109.5	H11A—C11—H11B	109.5
H6A—C6—H6C	109.5	C8—C11—H11C	109.5
H6B—C6—H6C	109.5	H11A—C11—H11C	109.5
O1—C7—N2	122.06 (15)	H11B—C11—H11C	109.5
O1—C7—C8	122.14 (14)	C1—N1—C2	116.32 (16)
N2—C7—C8	115.80 (13)	C7—N2—C1	127.83 (13)
C10—C8—C11	109.58 (19)	C7—N2—H2A	116.1
C10—C8—C9	109.95 (18)	C1—N2—H2A	116.1

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O1ⁱ	0.86	2.22	3.0644 (17)	168
C5—H5···O1	0.93	2.28	2.842 (2)	118

Symmetry code: (i) −x+3/2, y−1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O1ⁱ	0.86	2.22	3.0644 (17)	168
C5—H5···O1	0.93	2.28	2.842 (2)	118

Symmetry code: (i) −x+3/2, y−1/2, z.

Acknowledgements

The authors extend their appreciation to the Deanship of Scientific Research at King Saud University for its funding of this research through the research group project RGP-VPP-239.

References

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doi:10.1107/S1600536814003729

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