Crystal structure of 2,2-dimethyl-N-(pyridin-3-yl)propanamide

In the title compound, C₁₀H₁₄N₂O, the pyridine ring is inclined to the mean plane of the amide moiety [N-C(=O)C] by 17.60 (8)°. There is an intra­molecular C-H...O hydrogen bond present involving the carbonyl O atom. In the crystal, mol­ecules are linked via N-H...N hydrogen bonds, forming chains propagating along [100]. The tert-butyl group is disordered over two sets of sites with a refined occupancy ratio of 0.758 (12):0.242 (12).

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• Disorder in main residue
• R factor = 0.041
• wR factor = 0.127
• Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Low       Ueq as Compared to Neighbors for .....         C7 Check
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.271 Check

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          7 Note
PLAT003_ALERT_2_G Number of Uiso or Uij Restrained non-H Atoms ...          7 Report
PLAT007_ALERT_5_G Number of Unrefined Donor-H Atoms ..............          1 Report
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check
PLAT300_ALERT_4_G Atom Site Occupancy of >C8     is Constrained at      0.758 Check
PLAT300_ALERT_4_G Atom Site Occupancy of >C9     is Constrained at      0.758 Check
PLAT300_ALERT_4_G Atom Site Occupancy of >C10    is Constrained at      0.758 Check
PLAT300_ALERT_4_G Atom Site Occupancy of <C8A    is Constrained at      0.242 Check
PLAT300_ALERT_4_G Atom Site Occupancy of <C9A    is Constrained at      0.242 Check
PLAT300_ALERT_4_G Atom Site Occupancy of <C10A   is Constrained at      0.242 Check
PLAT301_ALERT_3_G Main Residue  Disorder ............ Percentage =         23 Note
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............        114 Note
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         23 Note
PLAT953_ALERT_1_G Reported (CIF) and Actual (FCF) Hmax Differ by .          1 Units

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  15 ALERT level G = General information/check it is not something unexpected

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   7 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Introduction

Pyridine derivatives are inter­esting compounds (Joule & Mills, 2000) since they show a range of biological activities (Thorat et al., 2013) such as anti­coagulant (de Candia et al., 2013) and anti­microbial (Abdel-Megeed et al., 2012) properties. Various simple and efficient processes have been developed for modification of the pyridine ring system (El-Hiti et al., 2015; Smith et al., 2013, Smith et al., 2012, Londregan et al., 2009; Turner, 1983). The X-ray crystal structures of related compounds have been reported (El-Hiti et al., 2014; Seidler et al., 2011; Koch et al., 2008; Mazik et al., 2004).

S2. Experimental

The title compound was obtained in 73% yield from the reaction of 3-amino­pyridine with pivaloyl chloride in the presence of tri­ethyl­amine in di­chloro­methane at 273 K for 15 min and then at room temperature for 2 h (Turner, 1983). Crystallization from a mixture of ethyl acetate and hexane gave colourless crystals of the title compound. The spectroscopic and analytical data for the title compound were identical with those reported previously (Turner, 1983)

S2.1. Refinement

The N- and C-bound H atoms were included in calculated positions and refined as riding: N—H = 0.86 Å, C—H = 0.93 - 0.98 Å with U_iso(H) = 1.5U_eq(C) for methyl H atoms and = 1.2U_eq(C) for other H atoms. The t-butyl group is disordered over two sites and was refined with bond length constraints to give a refined occupancy ratio of 0.758 (12):0.242 (12).

S3. Results and discussion

The molecular structure of the title compound is illustrated in Fig. 1. The pyridine ring is inclined to the mean plane of the amide moiety [N1—C6(═ O1)—C7] by 17.60 (8) °. There is an intra­molecular C—H···O hydrogen bond present involving the carbonyl O atom (Table 1).

In the crystal, molecules are linked via N—H···N hydrogen bonds forming chains propagating along [100]; see Table 1 and Fig. 2.

Related literature

For related biologically active pyridine derivatives, see: de Candia et al. (2013); Thorat et al. (2013); Abdel-Megeed et al. (2012). For pyridine ring-system modifications, see: El-Hiti et al. (2015); Smith et al. (2012, 2013); Londregan et al. (2009); Joule & Mills (2000); Turner (1983). For the crystal structures of related compounds, see: El-Hiti et al. (2014); Seidler et al. (2011); Koch et al. (2008); Mazik et al. (2004).

Structure description

Pyridine derivatives are inter­esting compounds (Joule & Mills, 2000) since they show a range of biological activities (Thorat et al., 2013) such as anti­coagulant (de Candia et al., 2013) and anti­microbial (Abdel-Megeed et al., 2012) properties. Various simple and efficient processes have been developed for modification of the pyridine ring system (El-Hiti et al., 2015; Smith et al., 2013, Smith et al., 2012, Londregan et al., 2009; Turner, 1983). The X-ray crystal structures of related compounds have been reported (El-Hiti et al., 2014; Seidler et al., 2011; Koch et al., 2008; Mazik et al., 2004).

The title compound was obtained in 73% yield from the reaction of 3-amino­pyridine with pivaloyl chloride in the presence of tri­ethyl­amine in di­chloro­methane at 273 K for 15 min and then at room temperature for 2 h (Turner, 1983). Crystallization from a mixture of ethyl acetate and hexane gave colourless crystals of the title compound. The spectroscopic and analytical data for the title compound were identical with those reported previously (Turner, 1983)

The molecular structure of the title compound is illustrated in Fig. 1. The pyridine ring is inclined to the mean plane of the amide moiety [N1—C6(═ O1)—C7] by 17.60 (8) °. There is an intra­molecular C—H···O hydrogen bond present involving the carbonyl O atom (Table 1).

In the crystal, molecules are linked via N—H···N hydrogen bonds forming chains propagating along [100]; see Table 1 and Fig. 2.

For related biologically active pyridine derivatives, see: de Candia et al. (2013); Thorat et al. (2013); Abdel-Megeed et al. (2012). For pyridine ring-system modifications, see: El-Hiti et al. (2015); Smith et al. (2012, 2013); Londregan et al. (2009); Joule & Mills (2000); Turner (1983). For the crystal structures of related compounds, see: El-Hiti et al. (2014); Seidler et al. (2011); Koch et al. (2008); Mazik et al. (2004).

Refinement details

The N- and C-bound H atoms were included in calculated positions and refined as riding: N—H = 0.86 Å, C—H = 0.93 - 0.98 Å with U_iso(H) = 1.5U_eq(C) for methyl H atoms and = 1.2U_eq(C) for other H atoms. The t-butyl group is disordered over two sites and was refined with bond length constraints to give a refined occupancy ratio of 0.758 (12):0.242 (12).

Computing details

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, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures

	Fig. 1. The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. Only the major component of the disordered t-butyl group is shown.
	Fig. 2. Crystal packing of the title compound, viewed along the b axis, with the N—H···N interactions shown as dashed lines (see Table 1 for details). The minor component of the disordered t-butyl group has been omitted for clarity.

2,2-Dimethyl-N-(pyridin-3-yl)propanamide

Crystal data

C10H14N2O	Dx = 1.141 Mg m^−3
Mr = 178.23	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, Pbca	Cell parameters from 3061 reflections
a = 11.2453 (3) Å	θ = 5.0–73.4°
b = 10.5272 (3) Å	µ = 0.60 mm^−1
c = 17.5339 (6) Å	T = 293 K
V = 2075.69 (11) Å^3	Plate, colourless
Z = 8	0.23 × 0.19 × 0.06 mm
F(000) = 768

Data collection

Agilent SuperNova (Dual, Cu at zero, Atlas) diffractometer	2065 independent reflections
Radiation source: sealed X-ray tube, SuperNova (Cu) X-ray Source	1722 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.017
ω scans	θmax = 73.8°, θmin = 5.1°
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	h = −14→8
Tmin = 0.840, Tmax = 1.000	k = −13→12
7164 measured reflections	l = −20→21

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.041	w = 1/[σ^2(Fo^2) + (0.0688P)^2 + 0.2387P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.127	(Δ/σ)max < 0.001
S = 1.05	Δρmax = 0.19 e Å^−3
2065 reflections	Δρmin = −0.16 e Å^−3
153 parameters	Extinction correction: SHELXL2013 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
114 restraints	Extinction coefficient: 0.0016 (4)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
C1	0.72804 (10)	0.10403 (12)	0.27358 (7)	0.0490 (3)
C2	0.61380 (11)	0.14128 (14)	0.25328 (8)	0.0585 (4)
H2	0.5822	0.2140	0.2756	0.070*
C3	0.59204 (13)	−0.02662 (15)	0.17123 (8)	0.0663 (4)
H3	0.5452	−0.0722	0.1371	0.080*
C4	0.70473 (13)	−0.06915 (16)	0.18680 (9)	0.0702 (4)
H4	0.7344	−0.1414	0.1630	0.084*
C5	0.77323 (12)	−0.00301 (14)	0.23832 (8)	0.0619 (4)
H5	0.8499	−0.0303	0.2494	0.074*
C6	0.76123 (12)	0.24951 (14)	0.38234 (8)	0.0585 (3)
C7	0.85629 (13)	0.29549 (15)	0.43884 (9)	0.0671 (4)
C8	0.9594 (3)	0.3605 (4)	0.3935 (2)	0.0798 (10)	0.758 (12)
H8A	0.9277	0.4278	0.3627	0.120*	0.758 (12)
H8B	0.9974	0.2988	0.3613	0.120*	0.758 (12)
H8C	1.0165	0.3947	0.4287	0.120*	0.758 (12)
C9	0.9077 (5)	0.1835 (4)	0.4813 (4)	0.0838 (11)	0.758 (12)
H9A	0.9680	0.2125	0.5159	0.126*	0.758 (12)
H9B	0.9421	0.1250	0.4455	0.126*	0.758 (12)
H9C	0.8458	0.1417	0.5094	0.126*	0.758 (12)
C10	0.8023 (4)	0.3941 (7)	0.4916 (4)	0.1205 (18)	0.758 (12)
H10A	0.7365	0.3574	0.5186	0.181*	0.758 (12)
H10B	0.7751	0.4653	0.4621	0.181*	0.758 (12)
H10C	0.8613	0.4222	0.5274	0.181*	0.758 (12)
C8A	0.9208 (16)	0.4067 (14)	0.4095 (8)	0.108 (4)	0.242 (12)
H8D	0.9534	0.3873	0.3602	0.162*	0.242 (12)
H8E	0.9841	0.4281	0.4439	0.162*	0.242 (12)
H8F	0.8672	0.4772	0.4052	0.162*	0.242 (12)
C9A	0.9385 (16)	0.1880 (15)	0.4658 (11)	0.089 (4)	0.242 (12)
H9D	0.8920	0.1137	0.4766	0.133*	0.242 (12)
H9E	0.9796	0.2142	0.5111	0.133*	0.242 (12)
H9F	0.9953	0.1690	0.4265	0.133*	0.242 (12)
C10A	0.7832 (11)	0.3342 (17)	0.5131 (6)	0.098 (4)	0.242 (12)
H10D	0.7211	0.3924	0.4993	0.147*	0.242 (12)
H10E	0.8355	0.3739	0.5491	0.147*	0.242 (12)
H10F	0.7488	0.2595	0.5355	0.147*	0.242 (12)
N1	0.79882 (8)	0.16796 (11)	0.32735 (6)	0.0543 (3)
H1	0.8741	0.1539	0.3252	0.065*
N2	0.54740 (9)	0.07752 (13)	0.20320 (7)	0.0650 (3)
O1	0.65818 (9)	0.28385 (14)	0.38687 (7)	0.0885 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0369 (6)	0.0624 (7)	0.0478 (6)	0.0007 (5)	0.0006 (5)	0.0031 (5)
C2	0.0400 (6)	0.0715 (8)	0.0640 (7)	0.0064 (6)	−0.0046 (5)	−0.0063 (6)
C3	0.0529 (7)	0.0841 (9)	0.0617 (8)	−0.0037 (7)	−0.0065 (6)	−0.0111 (7)
C4	0.0630 (9)	0.0778 (9)	0.0697 (9)	0.0116 (7)	−0.0067 (7)	−0.0172 (7)
C5	0.0450 (7)	0.0766 (8)	0.0641 (8)	0.0130 (6)	−0.0051 (6)	−0.0078 (6)
C6	0.0461 (7)	0.0715 (8)	0.0579 (7)	0.0057 (6)	−0.0020 (6)	−0.0039 (6)
C7	0.0620 (8)	0.0739 (8)	0.0653 (8)	−0.0024 (7)	−0.0092 (6)	−0.0103 (7)
C8	0.0716 (17)	0.0753 (17)	0.0926 (19)	−0.0182 (13)	−0.0135 (13)	0.0017 (14)
C9	0.089 (3)	0.101 (2)	0.062 (2)	−0.0202 (16)	−0.0235 (18)	0.0146 (16)
C10	0.098 (2)	0.134 (4)	0.129 (4)	−0.002 (3)	−0.004 (2)	−0.073 (3)
C8A	0.129 (8)	0.107 (7)	0.087 (6)	−0.026 (6)	−0.027 (6)	0.000 (6)
C9A	0.080 (7)	0.116 (7)	0.071 (7)	0.008 (6)	−0.023 (5)	−0.011 (5)
C10A	0.102 (6)	0.115 (8)	0.076 (5)	0.013 (6)	−0.026 (4)	−0.046 (5)
N1	0.0341 (5)	0.0708 (7)	0.0581 (6)	0.0041 (4)	−0.0035 (4)	−0.0056 (5)
N2	0.0408 (6)	0.0867 (8)	0.0676 (7)	0.0032 (5)	−0.0078 (5)	−0.0079 (6)
O1	0.0543 (6)	0.1273 (10)	0.0838 (8)	0.0235 (6)	−0.0048 (5)	−0.0356 (7)

Geometric parameters (Å, º)

C1—C5	1.3820 (19)	C8—H8A	0.9600
C1—C2	1.3895 (17)	C8—H8B	0.9600
C1—N1	1.4054 (16)	C8—H8C	0.9600
C2—N2	1.3339 (18)	C9—H9A	0.9600
C2—H2	0.9300	C9—H9B	0.9600
C3—N2	1.3297 (19)	C9—H9C	0.9600
C3—C4	1.372 (2)	C10—H10A	0.9600
C3—H3	0.9300	C10—H10B	0.9600
C4—C5	1.376 (2)	C10—H10C	0.9600
C4—H4	0.9300	C8A—H8D	0.9600
C5—H5	0.9300	C8A—H8E	0.9600
C6—O1	1.2165 (17)	C8A—H8F	0.9600
C6—N1	1.3585 (17)	C9A—H9D	0.9600
C6—C7	1.5356 (19)	C9A—H9E	0.9600
C7—C8A	1.470 (7)	C9A—H9F	0.9600
C7—C9	1.510 (4)	C10A—H10D	0.9600
C7—C10	1.517 (4)	C10A—H10E	0.9600
C7—C9A	1.536 (8)	C10A—H10F	0.9600
C7—C8	1.563 (3)	N1—H1	0.8600
C7—C10A	1.593 (7)
C5—C1—C2	117.09 (12)	H8B—C8—H8C	109.5
C5—C1—N1	118.83 (10)	C7—C9—H9A	109.5
C2—C1—N1	124.07 (11)	C7—C9—H9B	109.5
N2—C2—C1	122.97 (12)	H9A—C9—H9B	109.5
N2—C2—H2	118.5	C7—C9—H9C	109.5
C1—C2—H2	118.5	H9A—C9—H9C	109.5
N2—C3—C4	122.28 (13)	H9B—C9—H9C	109.5
N2—C3—H3	118.9	C7—C10—H10A	109.5
C4—C3—H3	118.9	C7—C10—H10B	109.5
C3—C4—C5	118.86 (14)	H10A—C10—H10B	109.5
C3—C4—H4	120.6	C7—C10—H10C	109.5
C5—C4—H4	120.6	H10A—C10—H10C	109.5
C4—C5—C1	120.02 (12)	H10B—C10—H10C	109.5
C4—C5—H5	120.0	C7—C8A—H8D	109.5
C1—C5—H5	120.0	C7—C8A—H8E	109.5
O1—C6—N1	122.04 (13)	H8D—C8A—H8E	109.5
O1—C6—C7	121.83 (13)	C7—C8A—H8F	109.5
N1—C6—C7	116.13 (11)	H8D—C8A—H8F	109.5
C9—C7—C10	112.8 (3)	H8E—C8A—H8F	109.5
C8A—C7—C6	111.6 (5)	C7—C9A—H9D	109.5
C9—C7—C6	109.8 (3)	C7—C9A—H9E	109.5
C10—C7—C6	109.3 (2)	H9D—C9A—H9E	109.5
C8A—C7—C9A	113.4 (7)	C7—C9A—H9F	109.5
C6—C7—C9A	112.7 (9)	H9D—C9A—H9F	109.5
C9—C7—C8	107.9 (2)	H9E—C9A—H9F	109.5
C10—C7—C8	107.9 (2)	C7—C10A—H10D	109.5
C6—C7—C8	109.05 (17)	C7—C10A—H10E	109.5
C8A—C7—C10A	109.7 (5)	H10D—C10A—H10E	109.5
C6—C7—C10A	104.4 (5)	C7—C10A—H10F	109.5
C9A—C7—C10A	104.3 (6)	H10D—C10A—H10F	109.5
C7—C8—H8A	109.5	H10E—C10A—H10F	109.5
C7—C8—H8B	109.5	C6—N1—C1	127.05 (10)
H8A—C8—H8B	109.5	C6—N1—H1	116.5
C7—C8—H8C	109.5	C1—N1—H1	116.5
H8A—C8—H8C	109.5	C3—N2—C2	118.76 (11)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1	0.93	2.25	2.8263 (18)	119
N1—H1···N2^i	0.86	2.17	3.0012 (15)	164

Symmetry code: (i) x+1/2, y, −z+1/2.