N-[3-Methyl-1-phenyl-1-(1H-tetra­zol-1-yl)butan-2-yl]acetamide

Geetha, S.; Yuva Priya, M.K.; Chandralekha, K.; Thennarasu, S.; Lakshmi, S.

doi:10.1107/S2414314616018101

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 1| Part 11| November 2016| x161810

https://doi.org/10.1107/S2414314616018101

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N-[3-Methyl-1-phenyl-1-(1H-tetrazol-1-yl)butan-2-yl]acetamide

Selvaraj Geetha,^a Muniraj Krishnaveni Yuva Priya,^b Kuppan Chandralekha,^c Sathiah Thennarasu ^b and Srinivasakannan Lakshmi ^c ^*

^aDepartment of Physics, Chevalier T. Thomas Elizabeth College for Women, Sembium, Chennai 600 011, India, ^bCentral Leather Research Institute, Organic Chemistry division, Adyar, Chennai 600 020, India, and ^cDepartment of Physics, S.D.N.B. Vaishnav College for Women, Chromepet, Chennai 600 044, India
^*Correspondence e-mail: lakssdnbvc@gmail.com

Edited by C. Rizzoli, Universita degli Studi di Parma, Italy (Received 24 October 2016; accepted 10 November 2016; online 15 November 2016)

In the molecule of the title compound, C₁₄H₁₉N₅O, the dihedral angle formed between the tetrazole and phenyl rings is 68.39 (4)°. In the crystal, molecules are linked by N—H⋯N, C—H⋯N and C—H⋯O hydrogen bonds to form two-dimensional networks extending parallel to the bc plane.

Keywords: crystal structure; tetrazole; acetamide; hydrogen bonds.

CCDC reference: 1516411

Structure description

Compounds containing a tetrazole ring have attracted much attention in medicinal chemistry (Alam & Nasrollahzadeh, 2009 ). Tetrazoles are reported to exhibits antihypertensive (Sharma et al., 2010 ), antimicrobial (Yildirir et al., 2009 ), antibacterial, antifungal (Dhayanithi et al., 2011 ) and anticancer activities (Bhaskar & Mohite, 2010 ). These functional units exhibit strong networking ability as ligands. They act as mono-, bi- or multidentate ligands due to the electron-donating nature of the four nitrogen atoms in the tetrazole moiety (Wang et al., 2005 ).

In the title compound (Fig. 1), the bond between the two chiral carbons C7 and C8 acts as the bridge connecting the phenyl ring, the 1-H tetrazole ring and the acetamide unit. The dihedral angle between the tetrazole ring (N1–N4, C14) and the phenyl ring (C1–C6) is 68.39 (4)°. The mean plane through the acetamide unit (N5, C12, C13, O1) forms dihedral angles of 62.00 (6) and 13.23 (6)° with the tetrazole and phenyl rings, respectively.

Figure 1
The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.

In the crystal, the molecules are linked through C—H⋯O, C—H⋯N and N—H⋯N hydrogen bonds (Table 1) into two-dimensional networks extending parallel to the bc plane (Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N5—H5A⋯N2ⁱ	0.844 (18)	2.452 (18)	3.2579 (17)	160.0 (15)
C6—H6⋯O1ⁱⁱ	0.93	2.43	3.356 (2)	171
C7—H7⋯N3ⁱ	0.98	2.48	3.4055 (19)	157
C14—H14⋯O1ⁱⁱ	0.93	2.27	3.1728 (19)	163
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z.

Figure 2
Partial crystal packing of the title compound showing the formation of a two-dimensional network parallel to the bc plane via N—H⋯N, C—H⋯O and C—H⋯N hydrogen bonds (dashed lines).

Synthesis and crystallization

A Mannich condensation reaction involving benzaldehye (200 mmol), isobutyl methyl ketone (100 mmol) and ammonium acetate (100 mmol) in 70 ml methanol at 70°C for 2 h afforded the respective piperidinone as crystals. The crystals were washed with methanol, dried completely under vacuum, then converted into the hydrochloride form by dissolving them in 30 ml ethanol and 20 ml ether and adding an equivalent volume of concentrated hydrochloric acid dropwise. 2 g of the precipitate obtained was gradually added to a beaker containing 10 ml of concentrated sulfuric acid in ice-cold condition, dissolved thoroughly and kept at room temperature with continuous stirring. 0.65 g of sodium azide was then added in small quantities to the beaker. On addition of sodium azide, a foam formed which subsequently subsided due to liberation of nitrogen. The solution was transferred into a beaker containing ice and neutralized with 4 M sodium hydroxide. The white precipitate formed was filtered through a Buchner funnel, vacuum dried and recrystallized with ethanol. The resulting lactam was cleaved under acidic conditions (6 M HCl) to form the substituted vicinal diamine. Conversion of the hydrochloride salt of the vicinal diamine into the free diamine was performed using 2 mol of sodium acetate. The vicinal diamine was then converted into acetylated 1-substituted tetrazole in the presence of 2 mol of sodium azide and 2 mol of triethyl orthoformate at 60°C in a glacial acetic acid medium. The compound obtained was then dissolved in methanol, transferred to a 15 ml vial, and the vial wrapped with tissue paper for controlled evaporation of the solvent without contamination. Single crystals suitable for X-ray analysis were formed after three days.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₄H₁₉N₅O
M_r	273.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	9.7056 (6), 7.7663 (5), 20.2620 (9)
β (°)	93.490 (2)
V (Å³)	1524.45 (15)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.08
Crystal size (mm)	0.35 × 0.30 × 0.30

Data collection
Diffractometer	Bruker Kappa APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2004 )
T_min, T_max	0.740, 0.976
No. of measured, independent and observed [I > 2σ(I)] reflections	10998, 3760, 2712
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.134, 1.02
No. of reflections	3760
No. of parameters	188
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.17
Computer programs: APEX2 and SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ), PLATON (Spek, 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1516411

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314616018101/rz4006sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616018101/rz4006Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314616018101/rz4006Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

N-[3-Methyl-1-phenyl-1-(1H-tetrazol-1-yl)butan-2-yl]acetamide top

Crystal data top

C₁₄H₁₉N₅O	F(000) = 584
M_r = 273.34	D_x = 1.191 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 393 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 9.7056 (6) Å	Cell parameters from 3760 reflections
b = 7.7663 (5) Å	θ = 2.8–28.3°
c = 20.2620 (9) Å	µ = 0.08 mm⁻¹
β = 93.490 (2)°	T = 296 K
V = 1524.45 (15) Å³	Block, colourless
Z = 4	0.35 × 0.30 × 0.30 mm

Data collection top

Bruker Kappa APEXII CCD diffractometer	3760 independent reflections
Radiation source: fine-focus sealed tube	2712 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
Bruker axs kappa apex2 CCD Diffractometer scans	θ_max = 28.3°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −12→12
T_min = 0.740, T_max = 0.976	k = −10→10
10998 measured reflections	l = −26→16

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.047	Hydrogen site location: mixed
wR(F²) = 0.134	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ²(F_o²) + (0.0588P)² + 0.4088P] where P = (F_o² + 2F_c²)/3
3760 reflections	(Δ/σ)_max = 0.010
188 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Special details top

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

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

	x	y	z	U_iso*/U_eq
O1	0.61825 (12)	0.64603 (18)	0.04105 (5)	0.0600 (3)
N1	0.43416 (11)	0.38123 (15)	0.15539 (5)	0.0342 (3)
N2	0.48431 (16)	0.3137 (2)	0.21287 (6)	0.0556 (4)
N3	0.57528 (16)	0.2002 (2)	0.19824 (7)	0.0605 (4)
N4	0.58598 (13)	0.19027 (18)	0.13256 (7)	0.0484 (3)
N5	0.50558 (12)	0.72547 (16)	0.12972 (6)	0.0388 (3)
H5A	0.5130 (17)	0.774 (2)	0.1670 (9)	0.049 (5)*
C1	0.18648 (14)	0.44056 (18)	0.13683 (7)	0.0374 (3)
C2	0.09223 (18)	0.4295 (3)	0.18515 (9)	0.0616 (5)
H2	0.1152	0.4707	0.2275	0.074*
C3	−0.0371 (2)	0.3568 (3)	0.17039 (13)	0.0847 (7)
H3	−0.1001	0.3499	0.2031	0.102*
C4	−0.07241 (19)	0.2958 (3)	0.10887 (13)	0.0788 (6)
H4	−0.1590	0.2474	0.0995	0.095*
C5	0.02009 (18)	0.3061 (3)	0.06068 (10)	0.0631 (5)
H5	−0.0038	0.2645	0.0185	0.076*
C6	0.14894 (15)	0.3779 (2)	0.07445 (8)	0.0462 (4)
H6	0.2111	0.3842	0.0414	0.055*
C7	0.32751 (14)	0.51735 (18)	0.15342 (6)	0.0349 (3)
H7	0.3268	0.5674	0.1978	0.042*
C8	0.37089 (14)	0.65989 (18)	0.10615 (6)	0.0349 (3)
H8	0.3817	0.6063	0.0630	0.042*
C9	0.26314 (16)	0.8039 (2)	0.09599 (7)	0.0448 (4)
H9	0.1749	0.7495	0.0822	0.054*
C10	0.2413 (2)	0.9070 (3)	0.15828 (9)	0.0670 (5)
H10A	0.3262	0.9619	0.1731	0.100*
H10B	0.2121	0.8312	0.1922	0.100*
H10C	0.1717	0.9929	0.1489	0.100*
C11	0.3024 (2)	0.9215 (2)	0.04006 (8)	0.0606 (5)
H11A	0.2328	1.0084	0.0326	0.091*
H11B	0.3096	0.8550	0.0005	0.091*
H11C	0.3895	0.9754	0.0518	0.091*
C12	0.61938 (15)	0.71366 (19)	0.09555 (7)	0.0418 (3)
C13	0.74903 (18)	0.7856 (3)	0.12893 (10)	0.0612 (5)
H13A	0.8277	0.7309	0.1115	0.092*
H13B	0.7493	0.7647	0.1756	0.092*
H13C	0.7531	0.9074	0.1210	0.092*
C14	0.49788 (15)	0.30355 (19)	0.10746 (7)	0.0412 (3)
H14	0.4822	0.3264	0.0626	0.049*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0576 (7)	0.0833 (9)	0.0399 (6)	−0.0092 (6)	0.0106 (5)	−0.0082 (6)
N1	0.0361 (6)	0.0374 (6)	0.0285 (5)	−0.0026 (5)	−0.0029 (4)	0.0043 (5)
N2	0.0667 (9)	0.0659 (10)	0.0332 (7)	0.0124 (8)	−0.0060 (6)	0.0102 (6)
N3	0.0647 (9)	0.0653 (10)	0.0501 (8)	0.0157 (8)	−0.0092 (7)	0.0129 (7)
N4	0.0438 (7)	0.0479 (8)	0.0530 (8)	0.0046 (6)	−0.0004 (6)	0.0068 (6)
N5	0.0420 (7)	0.0423 (7)	0.0318 (6)	−0.0075 (5)	−0.0008 (5)	−0.0065 (5)
C1	0.0350 (7)	0.0378 (8)	0.0399 (7)	0.0017 (6)	0.0054 (5)	0.0063 (6)
C2	0.0551 (10)	0.0821 (14)	0.0493 (9)	−0.0016 (9)	0.0179 (8)	0.0044 (9)
C3	0.0517 (11)	0.1155 (19)	0.0907 (16)	−0.0091 (12)	0.0343 (11)	0.0137 (14)
C4	0.0398 (10)	0.0940 (16)	0.1027 (17)	−0.0163 (10)	0.0056 (10)	0.0085 (14)
C5	0.0450 (9)	0.0713 (13)	0.0715 (12)	−0.0107 (9)	−0.0085 (8)	−0.0026 (10)
C6	0.0370 (7)	0.0551 (9)	0.0464 (8)	−0.0064 (7)	0.0027 (6)	−0.0019 (7)
C7	0.0387 (7)	0.0390 (7)	0.0270 (6)	0.0011 (6)	0.0016 (5)	−0.0017 (5)
C8	0.0386 (7)	0.0351 (7)	0.0306 (6)	−0.0035 (6)	−0.0009 (5)	−0.0012 (5)
C9	0.0461 (8)	0.0410 (8)	0.0465 (8)	0.0017 (7)	−0.0036 (6)	0.0025 (6)
C10	0.0816 (13)	0.0610 (12)	0.0592 (11)	0.0248 (10)	0.0116 (9)	−0.0017 (9)
C11	0.0816 (13)	0.0461 (10)	0.0534 (10)	0.0048 (9)	−0.0025 (9)	0.0108 (8)
C12	0.0440 (8)	0.0414 (8)	0.0396 (8)	−0.0044 (7)	0.0000 (6)	0.0053 (6)
C13	0.0458 (9)	0.0648 (12)	0.0720 (12)	−0.0081 (8)	−0.0040 (8)	−0.0034 (9)
C14	0.0436 (8)	0.0442 (8)	0.0356 (7)	0.0023 (6)	0.0014 (6)	0.0030 (6)

Geometric parameters (Å, º) top

O1—C12	1.2221 (18)	C5—H5	0.9300
N1—C14	1.3276 (18)	C6—H6	0.9300
N1—N2	1.3413 (16)	C7—C8	1.5392 (19)
N1—C7	1.4784 (18)	C7—H7	0.9800
N2—N3	1.295 (2)	C8—C9	1.536 (2)
N3—N4	1.3434 (19)	C8—H8	0.9800
N4—C14	1.3079 (19)	C9—C10	1.520 (2)
N5—C12	1.3420 (19)	C9—C11	1.522 (2)
N5—C8	1.4562 (17)	C9—H9	0.9800
N5—H5A	0.844 (18)	C10—H10A	0.9600
C1—C6	1.382 (2)	C10—H10B	0.9600
C1—C2	1.383 (2)	C10—H10C	0.9600
C1—C7	1.5120 (19)	C11—H11A	0.9600
C2—C3	1.392 (3)	C11—H11B	0.9600
C2—H2	0.9300	C11—H11C	0.9600
C3—C4	1.358 (3)	C12—C13	1.500 (2)
C3—H3	0.9300	C13—H13A	0.9600
C4—C5	1.368 (3)	C13—H13B	0.9600
C4—H4	0.9300	C13—H13C	0.9600
C5—C6	1.382 (2)	C14—H14	0.9300

C14—N1—N2	107.28 (12)	C9—C8—C7	113.40 (11)
C14—N1—C7	131.43 (11)	N5—C8—H8	107.4
N2—N1—C7	121.30 (11)	C9—C8—H8	107.4
N3—N2—N1	106.48 (12)	C7—C8—H8	107.4
N2—N3—N4	111.16 (12)	C10—C9—C11	110.85 (15)
C14—N4—N3	104.96 (13)	C10—C9—C8	113.59 (13)
C12—N5—C8	123.88 (12)	C11—C9—C8	109.73 (13)
C12—N5—H5A	117.7 (11)	C10—C9—H9	107.5
C8—N5—H5A	118.4 (11)	C11—C9—H9	107.5
C6—C1—C2	118.47 (14)	C8—C9—H9	107.5
C6—C1—C7	121.79 (12)	C9—C10—H10A	109.5
C2—C1—C7	119.73 (14)	C9—C10—H10B	109.5
C1—C2—C3	119.98 (18)	H10A—C10—H10B	109.5
C1—C2—H2	120.0	C9—C10—H10C	109.5
C3—C2—H2	120.0	H10A—C10—H10C	109.5
C4—C3—C2	120.85 (17)	H10B—C10—H10C	109.5
C4—C3—H3	119.6	C9—C11—H11A	109.5
C2—C3—H3	119.6	C9—C11—H11B	109.5
C3—C4—C5	119.66 (18)	H11A—C11—H11B	109.5
C3—C4—H4	120.2	C9—C11—H11C	109.5
C5—C4—H4	120.2	H11A—C11—H11C	109.5
C4—C5—C6	120.27 (19)	H11B—C11—H11C	109.5
C4—C5—H5	119.9	O1—C12—N5	122.22 (14)
C6—C5—H5	119.9	O1—C12—C13	121.92 (14)
C5—C6—C1	120.77 (15)	N5—C12—C13	115.85 (14)
C5—C6—H6	119.6	C12—C13—H13A	109.5
C1—C6—H6	119.6	C12—C13—H13B	109.5
N1—C7—C1	110.29 (11)	H13A—C13—H13B	109.5
N1—C7—C8	108.27 (10)	C12—C13—H13C	109.5
C1—C7—C8	115.06 (11)	H13A—C13—H13C	109.5
N1—C7—H7	107.6	H13B—C13—H13C	109.5
C1—C7—H7	107.6	N4—C14—N1	110.12 (13)
C8—C7—H7	107.6	N4—C14—H14	124.9
N5—C8—C9	112.30 (12)	N1—C14—H14	124.9
N5—C8—C7	108.76 (11)

C14—N1—N2—N3	0.25 (17)	C6—C1—C7—C8	52.19 (19)
C7—N1—N2—N3	−179.60 (13)	C2—C1—C7—C8	−128.80 (15)
N1—N2—N3—N4	−0.4 (2)	C12—N5—C8—C9	−116.60 (15)
N2—N3—N4—C14	0.3 (2)	C12—N5—C8—C7	117.06 (14)
C6—C1—C2—C3	−0.1 (3)	N1—C7—C8—N5	−58.28 (13)
C7—C1—C2—C3	−179.13 (18)	C1—C7—C8—N5	177.83 (11)
C1—C2—C3—C4	0.1 (4)	N1—C7—C8—C9	176.01 (11)
C2—C3—C4—C5	−0.1 (4)	C1—C7—C8—C9	52.12 (16)
C3—C4—C5—C6	0.1 (4)	N5—C8—C9—C10	−58.69 (17)
C4—C5—C6—C1	0.0 (3)	C7—C8—C9—C10	65.11 (17)
C2—C1—C6—C5	0.1 (3)	N5—C8—C9—C11	66.00 (16)
C7—C1—C6—C5	179.09 (15)	C7—C8—C9—C11	−170.20 (12)
C14—N1—C7—C1	80.54 (17)	C8—N5—C12—O1	0.1 (2)
N2—N1—C7—C1	−99.66 (14)	C8—N5—C12—C13	−178.70 (14)
C14—N1—C7—C8	−46.17 (18)	N3—N4—C14—N1	−0.15 (18)
N2—N1—C7—C8	133.64 (13)	N2—N1—C14—N4	−0.06 (17)
C6—C1—C7—N1	−70.63 (16)	C7—N1—C14—N4	179.77 (13)
C2—C1—C7—N1	108.39 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5A···N2ⁱ	0.844 (18)	2.452 (18)	3.2579 (17)	160.0 (15)
C6—H6···O1ⁱⁱ	0.93	2.43	3.356 (2)	171
C7—H7···N3ⁱ	0.98	2.48	3.4055 (19)	157
C14—H14···O1ⁱⁱ	0.93	2.27	3.1728 (19)	163

Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, −y+1, −z.

Acknowledgements

The authors thank the single-crystal XRD facility, SAIF, IIT Madras, Chennai, for the data collection.

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