tert-Butyl N-{2-[bis­(prop-2-yn-1-yl)amino]­phen­yl}carbamate

Singh, M.K.; Agarwal, A.; Mahawar, C.; Awasthi, S.K.

doi:10.1107/S1600536811016862

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1382

doi:10.1107/S1600536811016862

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tert-Butyl N-{2-[bis(prop-2-yn-1-yl)amino]phenyl}carbamate

Manavendra K. Singh,^a Alka Agarwal,^a ^* Charu Mahawar ^a and Satish K. Awasthi ^b ^*

^aDepartment of Medicinal Chemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi 225 001, U.P. India, and ^bChemical Biology Laboratory, Department of Chemistry, University of Delhi 110 007, Delhi, India
^*Correspondence e-mail: dralka@bhu.ac.in, awasthisatish@yahoo.com

(Received 31 March 2011; accepted 4 May 2011; online 11 May 2011)

In the crystal of the title compound, C₁₇H₂₀N₂O₂, the molecules are linked by C—H⋯O interactions. Intramolecular C—H⋯O and N—H⋯N hydrogen bonds also occur.

Related literature

For applications of alkyne scaffolds in biology, medicinal and materials chemistry, see: Diederich et al. (2005 ); Stang & Diederich (1995 ); Lam et al. (1988 ); Patai (1994 ). For background to click chemistry, which involves 1,3-dipolar cycloaddition of an alkyne with an azide and is an efficient and highly versatile tool that has allowed the preparation of a variety of macromolecule conjugates such as sugars, peptides or proteins and DNA, see: Rostovtsev et al. (2002 ). For the synthesis, see: Lilienkampf et al. (2009 ). For intermolecular interactions, see: Steiner & Desiraju (1998 ). For intramolecular C—H⋯O hydrogen bonds, see: Smith et al. (1993 ).

Experimental

Crystal data

C₁₇H₂₀N₂O₂
M_r = 284.35
Monoclinic, C 2/c
a = 19.1936 (12) Å
b = 8.7181 (4) Å
c = 19.7619 (9) Å
β = 99.513 (5)°
V = 3261.3 (3) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.40 × 0.39 × 0.38 mm

Data collection

Oxford Diffraction Xcalibur Eos diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.953, T_max = 1.000
6969 measured reflections
4389 independent reflections
2427 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.156
S = 0.96
4389 reflections
194 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10B⋯O1ⁱ	0.97	2.55	3.512 (2)	171
C9—H9⋯O1ⁱⁱ	0.93	2.28	3.194 (3)	166
C2—H2⋯O1	0.93	2.32	2.911 (3)	121
N1—HN1⋯N2	0.810 (19)	2.28 (2)	2.703 (2)	114 (2)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ ; (ii) $[x, -y+2, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811016862/zj2008sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811016862/zj2008Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811016862/zj2008Isup3.cml

checkCIF report

Comment top

The carbon-carbon triple bond is an important and versatile functional group in organic chemistry. Alkynes are found in numerous natural products as well as in synthetic organic molecules. These alkyne scaffolds have various applications in biology, medicinal and material chemistry (Diederich et al., 2005; Stang & Diederich 1995; Lam et al., 1988; Patai 1994). Click chemistry developed by Sharpless (Rostovtsev et al., 2002) involves 1,3-dipolar cycloaddition of alkyne with azide as an efficient and highly versatile tool that has allowed to prepare a variety of macromolecule conjugates such as sugars, peptides or proteins and DNA. As part of our ongoing work on antimicrobial studies on small molecules, we characterized and report here the crystal structure of [2-(di-prop-2-ynyl-amino)phenyl]carbamic acid tert-butyl ester (Figure1).

In the crystal structure, the compound is stabilized by intermolecular interaction between C10—H10B···O1 and C9—H9···O1 (Steiner & Desiraju, 1998) and intramolecular hydrogen bond between C2—H2···O1 (Smith et al., 1993) and N1—HN1···N2 as seen in the crystal packing diagram along b axis (Table 1, Figure 2). Considering C1—C6 C13—C15 N1 N2 O1 O2 atom as plane A, C7 C8 C9 atom as plane B, C10 C11 C12 atom as plane C, the dihedral angels between planes A/B, A/C and B/C are 74.74°, 57.52°, 48.94° respectively, suggests that the molecule is not co-planar.

Related literature top

For applications of alkyne scaffolds in biology, medicinal and materials chemistry, see: Diederich et al. (2005); Stang & Diederich (1995); Lam et al. (1988); Patai (1994). For background to click chemistry, which involves 1,3-dipolar cycloaddition of an alkyne with an azide and is an efficient and highly versatile tool that has allowed the preparation of a variety of macromolecule conjugates such as sugars, peptides or proteins and DNA, see: Rostovtsev et al. (2002). For the synthesis, see: Lilienkampf et al. (2009). For intermolecular interactions, see: Steiner & Desiraju (1998). For intramolecular C—H···O hydrogen bonds, see: Smith et al. (1993).

Experimental top

The synthesis of the title compound was carried out according to the published procedure (Lilienkampf, et al., 2009). Briefly, to a solution of (2-aminophenyl)carbamic acid tert-butyl ester (1.5 g, 7.2 mmol) in dry acetone was added anhydrous K₂CO₃ (7.95 g, 54.6 m mol) and reaction mixture was refluxed for 15–30 minutes. Subsequently, KI (0.60 g m, 3.6 mmol) and propargyl bromide (0.75 ml, 7.8 mmol) were added and further refluxed the reaction mixture for 18 hrs. The reaction mixture was cooled, filtered, and the filtrate was evaporated in vacuo to give the product. The crude product was purified by column chromatography using hexane and dichloromethane (65:35) as eluent. The purified product was recrystallized from hexane-dichloromethane (1:1). The colourless crystals were obtained by slow evaporation of solvent at room temperature in several days. Yield: 20%.

¹H NMR (CDCl₃): 8.11 (bs, 1H, NH), 7.56–7.55 (m, 1H, Ar—H), 7.35- 7.32 (m, 1H, Ar—H), 7.19–7.14 (m, 1H, Ar—H), 6.99–6.94 (m, 1H, Ar—H), 3.83 (s, 4H, CH₂), 2.28 (s, 2H, CH), 1.51 (s, 9H, 3xCH₃).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. ORTEP diagram of molecule with thermal ellipsoids drawn at 50% probability level Color code: White: C; red: O; blue: N; white: H
	Fig. 2. Intermolecular interaction between C—H···O (blue line) and Intramolecular hydrogen bond (red line) showed in packing diagram of molecule along b-plane
	Fig. 3. The formation of the title compound.

tert-Butyl N-{2-[bis(prop-2-yn-1-yl)amino]phenyl}carbamate top

Crystal data top

C₁₇H₂₀N₂O₂	F(000) = 1216.0
M_r = 284.35	D_x = 1.158 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4389 reflections
a = 19.1936 (12) Å	θ = 3.2–29.0°
b = 8.7181 (4) Å	µ = 0.08 mm⁻¹
c = 19.7619 (9) Å	T = 293 K
β = 99.513 (5)°	Block, colourless
V = 3261.3 (3) Å³	0.40 × 0.39 × 0.38 mm
Z = 8

Data collection top

Oxford Diffraction Xcalibur Eos diffractometer	4389 independent reflections
Radiation source: fine-focus sealed tube	2427 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
ω scans	θ_max = 29.1°, θ_min = 3.2°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	h = −24→7
T_min = 0.953, T_max = 1.000	k = −10→10
6969 measured reflections	l = −23→26

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 0.96	w = 1/[σ²(F_o²) + (0.0754P)² + 1.325P] where P = (F_o² + 2F_c²)/3
4389 reflections	(Δ/σ)_max = 0.05
194 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₁₇H₂₀N₂O₂	V = 3261.3 (3) Å³
M_r = 284.35	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 19.1936 (12) Å	µ = 0.08 mm⁻¹
b = 8.7181 (4) Å	T = 293 K
c = 19.7619 (9) Å	0.40 × 0.39 × 0.38 mm
β = 99.513 (5)°

Data collection top

Oxford Diffraction Xcalibur Eos diffractometer	4389 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	2427 reflections with I > 2σ(I)
T_min = 0.953, T_max = 1.000	R_int = 0.019
6969 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	0 restraints
wR(F²) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 0.96	Δρ_max = 0.19 e Å⁻³
4389 reflections	Δρ_min = −0.19 e Å⁻³
194 parameters

Special details top

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
HN1	0.1292 (11)	0.706 (2)	0.4601 (9)	0.038 (5)*
N1	0.13858 (9)	0.78587 (19)	0.47962 (8)	0.0397 (4)
O2	0.05794 (7)	0.71231 (15)	0.53892 (6)	0.0505 (4)
N2	0.17096 (8)	0.68525 (17)	0.35922 (7)	0.0399 (4)
C1	0.18983 (9)	0.8707 (2)	0.45262 (8)	0.0362 (4)
O1	0.11848 (8)	0.93110 (16)	0.57014 (6)	0.0548 (4)
C13	0.10630 (10)	0.8202 (2)	0.53354 (8)	0.0380 (4)
C6	0.20658 (10)	0.8197 (2)	0.38966 (8)	0.0383 (4)
C2	0.22421 (11)	0.9975 (2)	0.48421 (10)	0.0454 (5)
H2	0.2130	1.0324	0.5256	0.055*
C11	0.19018 (12)	0.4288 (3)	0.31791 (9)	0.0510 (5)
C5	0.25792 (11)	0.8980 (2)	0.36113 (10)	0.0507 (5)
H5	0.2691	0.8655	0.3194	0.061*
C10	0.21577 (11)	0.5866 (2)	0.32379 (9)	0.0476 (5)
H10A	0.2168	0.6274	0.2783	0.057*
H10B	0.2637	0.5879	0.3489	0.057*
C8	0.10589 (12)	0.7963 (3)	0.25187 (10)	0.0586 (6)
C3	0.27519 (12)	1.0729 (2)	0.45480 (11)	0.0544 (5)
H3	0.2980	1.1581	0.4765	0.065*
C7	0.10173 (11)	0.7167 (2)	0.31671 (9)	0.0491 (5)
H7A	0.0771	0.6202	0.3064	0.059*
H7B	0.0739	0.7786	0.3431	0.059*
C14	0.00843 (11)	0.7249 (2)	0.58831 (9)	0.0484 (5)
C4	0.29225 (12)	1.0225 (2)	0.39370 (12)	0.0576 (6)
H4	0.3270	1.0727	0.3744	0.069*
C12	0.17318 (14)	0.2999 (3)	0.31334 (12)	0.0681 (7)
H12	0.1597	0.1974	0.3097	0.082*
C15	−0.03735 (16)	0.5849 (3)	0.57144 (14)	0.0852 (9)
H15A	−0.0629	0.5935	0.5255	0.128*
H15B	−0.0701	0.5772	0.6031	0.128*
H15C	−0.0081	0.4949	0.5750	0.128*
C9	0.11141 (16)	0.8551 (4)	0.20009 (13)	0.0838 (8)
H9	0.1158	0.9020	0.1587	0.101*
C16	0.04878 (15)	0.7145 (4)	0.66033 (11)	0.0833 (9)
H16A	0.0750	0.6203	0.6656	0.125*
H16B	0.0163	0.7169	0.6924	0.125*
H16C	0.0808	0.7996	0.6689	0.125*
C17	−0.03353 (15)	0.8709 (3)	0.57635 (15)	0.0854 (9)
H17A	−0.0585	0.8727	0.5300	0.128*
H17B	−0.0021	0.9572	0.5837	0.128*
H17C	−0.0668	0.8759	0.6076	0.128*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0456 (10)	0.0393 (9)	0.0381 (8)	−0.0030 (7)	0.0187 (7)	−0.0042 (7)
O2	0.0517 (9)	0.0599 (8)	0.0465 (7)	−0.0109 (7)	0.0271 (6)	−0.0086 (6)
N2	0.0396 (9)	0.0496 (9)	0.0328 (7)	0.0035 (7)	0.0129 (6)	0.0014 (6)
C1	0.0340 (10)	0.0386 (9)	0.0379 (9)	0.0065 (8)	0.0118 (7)	0.0075 (7)
O1	0.0565 (9)	0.0634 (9)	0.0486 (7)	−0.0082 (7)	0.0212 (6)	−0.0186 (7)
C13	0.0358 (10)	0.0462 (10)	0.0332 (8)	0.0030 (8)	0.0094 (7)	0.0006 (7)
C6	0.0362 (10)	0.0424 (10)	0.0386 (9)	0.0062 (8)	0.0126 (7)	0.0083 (7)
C2	0.0431 (11)	0.0422 (10)	0.0530 (11)	0.0036 (9)	0.0133 (8)	−0.0008 (8)
C11	0.0530 (13)	0.0616 (14)	0.0412 (10)	0.0101 (11)	0.0160 (9)	−0.0043 (9)
C5	0.0506 (13)	0.0553 (12)	0.0518 (11)	0.0017 (10)	0.0250 (9)	0.0092 (9)
C10	0.0457 (12)	0.0610 (13)	0.0391 (9)	0.0088 (10)	0.0155 (8)	−0.0007 (8)
C8	0.0522 (14)	0.0731 (15)	0.0499 (12)	0.0075 (12)	0.0066 (9)	0.0173 (10)
C3	0.0455 (13)	0.0434 (11)	0.0756 (14)	−0.0007 (10)	0.0141 (10)	0.0011 (10)
C7	0.0418 (12)	0.0638 (13)	0.0432 (10)	0.0022 (10)	0.0113 (8)	0.0076 (9)
C14	0.0456 (12)	0.0621 (12)	0.0435 (10)	0.0018 (10)	0.0247 (8)	0.0024 (9)
C4	0.0466 (13)	0.0529 (12)	0.0794 (14)	−0.0020 (10)	0.0287 (11)	0.0122 (11)
C12	0.0762 (18)	0.0616 (15)	0.0727 (15)	0.0037 (13)	0.0307 (13)	−0.0087 (11)
C15	0.081 (2)	0.095 (2)	0.0936 (18)	−0.0271 (16)	0.0533 (15)	−0.0110 (15)
C9	0.081 (2)	0.108 (2)	0.0634 (15)	0.0147 (17)	0.0150 (13)	0.0378 (15)
C16	0.086 (2)	0.121 (2)	0.0472 (13)	0.0107 (18)	0.0253 (12)	0.0175 (13)
C17	0.0630 (17)	0.093 (2)	0.110 (2)	0.0268 (15)	0.0427 (15)	0.0300 (16)

Geometric parameters (Å, º) top

N1—C13	1.352 (2)	C8—C7	1.471 (3)
N1—C1	1.404 (2)	C3—C4	1.374 (3)
N1—HN1	0.801 (19)	C3—H3	0.9300
O2—C13	1.338 (2)	C7—H7A	0.9700
O2—C14	1.475 (2)	C7—H7B	0.9700
N2—C6	1.438 (2)	C14—C17	1.504 (3)
N2—C7	1.476 (2)	C14—C16	1.507 (3)
N2—C10	1.472 (2)	C14—C15	1.509 (3)
C1—C2	1.382 (3)	C4—H4	0.9300
C1—C6	1.407 (2)	C12—H12	0.9300
O1—C13	1.207 (2)	C15—H15A	0.9600
C6—C5	1.392 (3)	C15—H15B	0.9600
C2—C3	1.384 (3)	C15—H15C	0.9600
C2—H2	0.9300	C9—H9	0.9300
C11—C12	1.170 (3)	C16—H16A	0.9600
C11—C10	1.459 (3)	C16—H16B	0.9600
C5—C4	1.374 (3)	C16—H16C	0.9600
C5—H5	0.9300	C17—H17A	0.9600
C10—H10A	0.9700	C17—H17B	0.9600
C10—H10B	0.9700	C17—H17C	0.9600
C8—C9	1.164 (3)

C13—N1—C1	128.60 (16)	C8—C7—H7A	108.7
C13—N1—HN1	118.4 (14)	N2—C7—H7A	108.7
C1—N1—HN1	113.0 (14)	C8—C7—H7B	108.7
C13—O2—C14	122.13 (14)	N2—C7—H7B	108.7
C6—N2—C7	114.07 (15)	H7A—C7—H7B	107.6
C6—N2—C10	113.60 (15)	O2—C14—C17	110.24 (16)
C7—N2—C10	112.31 (14)	O2—C14—C16	109.50 (18)
C2—C1—C6	119.35 (16)	C17—C14—C16	112.2 (2)
C2—C1—N1	124.15 (16)	O2—C14—C15	102.07 (16)
C6—C1—N1	116.50 (16)	C17—C14—C15	111.9 (2)
O1—C13—O2	125.71 (16)	C16—C14—C15	110.5 (2)
O1—C13—N1	125.54 (17)	C5—C4—C3	119.92 (19)
O2—C13—N1	108.74 (15)	C5—C4—H4	120.0
C5—C6—C1	118.91 (18)	C3—C4—H4	120.0
C5—C6—N2	123.34 (16)	C11—C12—H12	180.0
C1—C6—N2	117.72 (15)	C14—C15—H15A	109.5
C3—C2—C1	120.53 (18)	C14—C15—H15B	109.5
C3—C2—H2	119.7	H15A—C15—H15B	109.5
C1—C2—H2	119.7	C14—C15—H15C	109.5
C12—C11—C10	176.5 (2)	H15A—C15—H15C	109.5
C4—C5—C6	120.96 (19)	H15B—C15—H15C	109.5
C4—C5—H5	119.5	C8—C9—H9	180.0
C6—C5—H5	119.5	C14—C16—H16A	109.5
C11—C10—N2	111.90 (16)	C14—C16—H16B	109.5
C11—C10—H10A	109.2	H16A—C16—H16B	109.5
N2—C10—H10A	109.2	C14—C16—H16C	109.5
C11—C10—H10B	109.2	H16A—C16—H16C	109.5
N2—C10—H10B	109.2	H16B—C16—H16C	109.5
H10A—C10—H10B	107.9	C14—C17—H17A	109.5
C9—C8—C7	177.1 (3)	C14—C17—H17B	109.5
C4—C3—C2	120.3 (2)	H17A—C17—H17B	109.5
C4—C3—H3	119.8	C14—C17—H17C	109.5
C2—C3—H3	119.8	H17A—C17—H17C	109.5
C8—C7—N2	114.21 (17)	H17B—C17—H17C	109.5

C13—N1—C1—C2	10.1 (3)	N1—C1—C2—C3	178.67 (18)
C13—N1—C1—C6	−170.50 (17)	C1—C6—C5—C4	0.4 (3)
C14—O2—C13—O1	5.5 (3)	N2—C6—C5—C4	−177.51 (18)
C14—O2—C13—N1	−173.54 (16)	C12—C11—C10—N2	−149 (4)
C1—N1—C13—O1	−2.8 (3)	C6—N2—C10—C11	157.11 (15)
C1—N1—C13—O2	176.26 (16)	C7—N2—C10—C11	−71.6 (2)
C2—C1—C6—C5	0.5 (3)	C1—C2—C3—C4	0.0 (3)
N1—C1—C6—C5	−178.92 (16)	C9—C8—C7—N2	46 (6)
C2—C1—C6—N2	178.52 (16)	C6—N2—C7—C8	70.5 (2)
N1—C1—C6—N2	−0.9 (2)	C10—N2—C7—C8	−60.6 (2)
C7—N2—C6—C5	−96.4 (2)	C13—O2—C14—C17	57.2 (3)
C10—N2—C6—C5	34.0 (2)	C13—O2—C14—C16	−66.8 (2)
C7—N2—C6—C1	85.68 (18)	C13—O2—C14—C15	176.18 (18)
C10—N2—C6—C1	−143.86 (16)	C6—C5—C4—C3	−1.1 (3)
C6—C1—C2—C3	−0.7 (3)	C2—C3—C4—C5	0.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10B···O1ⁱ	0.97	2.55	3.512 (2)	171
C9—H9···O1ⁱⁱ	0.93	2.28	3.194 (3)	166
C2—H2···O1	0.93	2.32	2.911 (3)	121
N1—HN1···N2	0.810 (19)	2.28 (2)	2.703 (2)	114 (2)

Symmetry codes: (i) −x+1/2, −y+3/2, −z+1; (ii) x, −y+2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₇H₂₀N₂O₂
M_r	284.35
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	19.1936 (12), 8.7181 (4), 19.7619 (9)
β (°)	99.513 (5)
V (Å³)	3261.3 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.40 × 0.39 × 0.38

Data collection
Diffractometer	Oxford Diffraction Xcalibur Eos diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.953, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	6969, 4389, 2427
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.684

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.156, 0.96
No. of reflections	4389
No. of parameters	194
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.19

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10B···O1ⁱ	0.970	2.55	3.512 (2)	171
C9—H9···O1ⁱⁱ	0.930	2.28	3.194 (3)	166
C2—H2···O1	0.930	2.32	2.911 (3)	121
N1—HN1···N2	0.810 (19)	2.28 (2)	2.703 (2)	114 (2)

Symmetry codes: (i) −x+1/2, −y+3/2, −z+1; (ii) x, −y+2, z−1/2.

Acknowledgements

AA, MKS and CM are thankful to the University Grant Commission (scheme No. 34–311/2008), New Delhi, and Banaras Hindu University, Varanasi, India, for financial assistance. SKA is thankful to the University of Delhi, India, for financial assistance.

References

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