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ISSN: 2056-9890

N-[4-(Morpholinodiazen­yl)phen­yl]acetamide

aDepartment of Chemistry, Whittier College, 13406 Philadelphia Street, Whittier, CA 90608, USA, and bDepartment of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
*Correspondence e-mail: risovits@whittier.edu

(Received 11 November 2009; accepted 18 November 2009; online 25 November 2009)

The title compound, C12H16N4O2, is a member of a family of morpholine-substituted aromatic diazenes. Conjugation of the diazene group π-system and the lone pair of electrons of the morpholine N atom is evidenced by a lengthened N=N double bond of 1.2707 (19) Å and a shortened N—N single bond of 1.346 (2) Å. The bond angles at the morpholine N atom range from 113.52 (14) to 121.12 (14)°, indicating some degree of sp2 hybridization. The morpholine ring adopts a conventional chair conformation with the diazenyl group in the equatorial position. The diazenyl and acetamido groups are both twisted relative to the plane of the benzene ring by 12.3 (2) and 25.5 (3)°, respectively.

Related literature

The title compound was synthesized using a modification of the method of Sengupta et al. (1998[Sengupta, S., Bhattacharyya, S. & Sadhukhan, S. K. (1998). J. Chem. Soc. Perkin Trans. 1, pp. 275-277.]). For similar structures, see: Little et al. (2008[Little, V. R., Jenkins, H. & Vaughan, K. (2008). J. Chem. Crystallogr. 38, 447-452.]). For information about diazene derivatives, see: Chen et al. (2005[Chen, B., Flatt, A. K., Jian, H., Hudson, J. L. & Tour, J. M. (2005). Chem. Mater. 17, 4832-4836.]); Lalezari & Afgahi (1975[Lalezari, I. & Afgahi, F. (1975). J. Pharm. Sci. 64, 698-699.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L. & Orpen, A. G. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C12H16N4O2

  • Mr = 248.29

  • Monoclinic, P 21 /c

  • a = 12.6013 (4) Å

  • b = 10.6114 (3) Å

  • c = 9.2967 (2) Å

  • β = 93.874 (2)°

  • V = 1240.29 (6) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.77 mm−1

  • T = 90 K

  • 0.23 × 0.17 × 0.01 mm

Data collection
  • Bruker Kappa APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.843, Tmax = 0.992

  • 11437 measured reflections

  • 2249 independent reflections

  • 1655 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.095

  • S = 1.03

  • 2249 reflections

  • 168 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.20 e Å−3

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Diazene derivatives have found utility in various research areas (Lalezari & Afgahi, 1975; Chen et al., 2005). Our research uses morpholine-substituted aryl diazenes as easily handled and prepared equivalents for the in situ generation of diazonium ions that are then used in the synthesis of novel derivatives of trans–stilbene via a Heck-type reaction (Sengupta et al., 1998).

The structure of the title compound is shown in Figure 1. The N–N double bond adopted a trans-configuration. A N3–N2–N1 bond angle of 113.93 (14) ° deviates from the optimal trigonal planar geometry by approximately 6°. The diazene moiety, N3–N2–N1, exhibits π –delocalization, evidenced by N1–N2 and N2–N3 bond lengths of 1.346 (2) and 1.2707 (19) Å respectively. These values are between literature value of 1.222 Å for a N–N double bond and 1.420 Å for a N(sp2)–N(sp3) single bond (Allen et al., 1987) Morpholine nitrogen bond angles that ranged from 113.52 (14)–121.12 (14)° indicated that the morpholine nitrogen had some degree of sp2 hybridization and participated in π –delocalization. The morpholine ring adopted a conventional chair conformation,with the diazenyl group in the equitorial postion on the morpholine nitrogen, N3. The acetamino and diazene groups were found to be twisted 25.5 (3)° and 12.3 (2)° respectively from the plane of the phenyl ring. The structure of the title compound is similar to the structure of related diazenes (Little et al., 2008).

Related literature top

The title compound was synthesized using a modification of the method of Sengupta et al. (1998). For similar structures, see: Little et al. (2008). For information about diazene derivatives, see: Chen et al. (2005); Lalezari & Afgahi (1975). For bond-length data, see: Allen et al. (1987).

Experimental top

Synthetic procedures were carried out using standard techniques. Solvents and reagents were used as received. Melting points were determined in open capillaries and are uncorrected. 1H and 13C NMR spectra were recorded on a Jeol ECX 300 MHz spectrometer using TMS as the internal standard. The IR spectrum was recorded as a KBr disk on a JASCO 460 F T–IR.

4.26 g of N–(4-aminophenyl)acetamide (28.4 mmol) was added to 12.5 ml of 6 M HCl in an ice water bath and cooled to 0° C to yield a light pink precipitate. The solid was maintained at 0° C, and a solution of 2.08 g (30.09 mmol) of NaNO2 in 4.0 ml H2O was added dropwise with stirring over ten minutes; a dark green brown solution resulted. After stirring for twenty minutes, 2.70 ml morpholine (2.74 g, 31.42 mmol) was added dropwise in 10 minutes. Then saturated K2CO3 was added until pH of 8 was reached, and solution was stirred for ten minutes: a yellow brown suspension resulted. The tan solid was collected using vacuum filtration, washed well with water and dried in air. The crude product was recrystallized from a 1:3 benzene:cyclohexane mixture to give 3.55 g (50.4%) of 4-[(E)-(acetamidophenyl)diazenyl]-morpholine as a tan microcrystalline solid.

m.p. 448-449 K. IR (KBr) 3294, 3055, 2971, 1664, 1600 cm-1. 1H NMR (300 MHz, CD3CN): 2.03 (s, 3H), 3.67 (m, 4H), 3.77 (m, 4H), 7.33 (d, 2H), 7.51 (d, 2H), 8.33 (s, 1H). 13C NMR (75 MHz, DMSO–d6): 24.54, 48.33, 66.05, 119.89, 121.27, 138.28, 145.50, 168.75 p.p.m.. Rf = 0.61 (ethyl acetate)

Refinement top

H atoms on C were placed in idealized positions with C—H distances 0.95 - 0.99 Å and thereafter treated as riding. A torsional parameter was refined for the methyl group. The N—H hydrogen atom was placed from a difference map, and its coordinates were refined. Uiso for H were assigned as 1.2 times Ueq of the attached atoms (1.5 for methyl).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with displacement ellipsoids at the 50% probability level. H atoms are shown with arbitrary radius.
N-[4-(Morpholinodiazenyl)phenyl]acetamide top
Crystal data top
C12H16N4O2F(000) = 528
Mr = 248.29Dx = 1.330 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 1544 reflections
a = 12.6013 (4) Åθ = 3.5–67.6°
b = 10.6114 (3) ŵ = 0.77 mm1
c = 9.2967 (2) ÅT = 90 K
β = 93.874 (2)°Plate, colorless
V = 1240.29 (6) Å30.23 × 0.17 × 0.01 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer
2249 independent reflections
Radiation source: fine-focus sealed tube1655 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
phi and ω scansθmax = 68.8°, θmin = 3.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
h = 1514
Tmin = 0.843, Tmax = 0.992k = 1212
11437 measured reflectionsl = 711
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.095 w = 1/[σ2(Fo2) + (0.0421P)2 + 0.3P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
2249 reflectionsΔρmax = 0.20 e Å3
168 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0012 (2)
Crystal data top
C12H16N4O2V = 1240.29 (6) Å3
Mr = 248.29Z = 4
Monoclinic, P21/cCu Kα radiation
a = 12.6013 (4) ŵ = 0.77 mm1
b = 10.6114 (3) ÅT = 90 K
c = 9.2967 (2) Å0.23 × 0.17 × 0.01 mm
β = 93.874 (2)°
Data collection top
Bruker Kappa APEXII CCD area-detector
diffractometer
2249 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
1655 reflections with I > 2σ(I)
Tmin = 0.843, Tmax = 0.992Rint = 0.053
11437 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.095H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.20 e Å3
2249 reflectionsΔρmin = 0.20 e Å3
168 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
xyzUiso*/Ueq
O10.58539 (10)0.71775 (12)0.68342 (13)0.0281 (3)
O20.91392 (10)0.19398 (12)0.26306 (12)0.0260 (3)
N10.63437 (11)0.46590 (13)0.62337 (14)0.0203 (3)
N20.66849 (11)0.34581 (13)0.61964 (14)0.0198 (3)
N30.73809 (11)0.32649 (13)0.52939 (14)0.0204 (3)
N40.88774 (11)0.17257 (13)0.50181 (15)0.0179 (3)
H4N0.8936 (14)0.2115 (18)0.5884 (18)0.021*
C10.52108 (14)0.61813 (17)0.73287 (19)0.0249 (4)
H1A0.46090.60250.66100.030*
H1B0.49140.64340.82440.030*
C20.58485 (14)0.49823 (17)0.75637 (18)0.0224 (4)
H2A0.64040.51040.83570.027*
H2B0.53760.42890.78360.027*
C30.69258 (14)0.56752 (16)0.55717 (18)0.0218 (4)
H3A0.71160.54190.45980.026*
H3B0.75910.58590.61630.026*
C40.62278 (15)0.68384 (17)0.54677 (19)0.0258 (4)
H4A0.66370.75500.50950.031*
H4B0.56110.66790.47750.031*
C50.77020 (13)0.19715 (16)0.52560 (17)0.0181 (4)
C60.74615 (13)0.10620 (16)0.62701 (17)0.0199 (4)
H60.70410.12790.70440.024*
C70.78367 (13)0.01525 (16)0.61454 (17)0.0192 (4)
H70.76600.07730.68260.023*
C80.84737 (13)0.04798 (16)0.50304 (16)0.0169 (4)
C90.87227 (14)0.04281 (16)0.40320 (17)0.0188 (4)
H90.91550.02160.32700.023*
C100.83377 (13)0.16458 (16)0.41515 (17)0.0186 (4)
H100.85120.22650.34680.022*
C110.92053 (13)0.23624 (16)0.38778 (17)0.0189 (4)
C120.96655 (14)0.36422 (16)0.42131 (18)0.0217 (4)
H12A0.93060.42700.35790.033*
H12B0.95640.38550.52200.033*
H12C1.04270.36370.40580.033*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0306 (7)0.0194 (7)0.0348 (7)0.0004 (6)0.0055 (6)0.0053 (6)
O20.0442 (8)0.0191 (7)0.0147 (6)0.0039 (6)0.0025 (5)0.0009 (5)
N10.0226 (7)0.0150 (7)0.0236 (7)0.0021 (6)0.0038 (6)0.0025 (6)
N20.0215 (7)0.0184 (8)0.0195 (7)0.0007 (6)0.0002 (6)0.0021 (6)
N30.0221 (7)0.0192 (8)0.0199 (7)0.0012 (6)0.0009 (6)0.0028 (6)
N40.0243 (8)0.0160 (7)0.0136 (7)0.0016 (6)0.0025 (6)0.0012 (6)
C10.0229 (9)0.0227 (10)0.0293 (9)0.0014 (8)0.0027 (8)0.0037 (8)
C20.0232 (9)0.0229 (10)0.0215 (9)0.0006 (7)0.0040 (7)0.0033 (8)
C30.0244 (9)0.0168 (9)0.0247 (9)0.0009 (8)0.0042 (8)0.0008 (7)
C40.0296 (10)0.0185 (9)0.0294 (10)0.0005 (8)0.0023 (8)0.0016 (8)
C50.0173 (8)0.0173 (9)0.0190 (8)0.0002 (7)0.0025 (7)0.0032 (7)
C60.0197 (9)0.0225 (10)0.0179 (8)0.0005 (7)0.0029 (7)0.0027 (7)
C70.0218 (9)0.0198 (9)0.0162 (8)0.0010 (7)0.0016 (7)0.0010 (7)
C80.0185 (8)0.0169 (9)0.0148 (8)0.0001 (7)0.0018 (7)0.0022 (7)
C90.0214 (8)0.0198 (9)0.0152 (8)0.0001 (7)0.0018 (7)0.0013 (7)
C100.0220 (8)0.0180 (9)0.0157 (8)0.0021 (7)0.0001 (7)0.0023 (7)
C110.0207 (9)0.0180 (9)0.0179 (9)0.0009 (7)0.0010 (7)0.0009 (7)
C120.0277 (9)0.0182 (9)0.0194 (8)0.0023 (8)0.0030 (7)0.0020 (8)
Geometric parameters (Å, º) top
O1—C11.427 (2)C3—H3B0.9900
O1—C41.430 (2)C4—H4A0.9900
O2—C111.2407 (19)C4—H4B0.9900
N1—N21.346 (2)C5—C101.388 (2)
N1—C21.463 (2)C5—C61.397 (2)
N1—C31.463 (2)C6—C71.380 (2)
N2—N31.2707 (19)C6—H60.9500
N3—C51.432 (2)C7—C81.397 (2)
N4—C111.345 (2)C7—H70.9500
N4—C81.417 (2)C8—C91.388 (2)
N4—H4N0.903 (17)C9—C101.387 (2)
C1—C21.513 (2)C9—H90.9500
C1—H1A0.9900C10—H100.9500
C1—H1B0.9900C11—C121.501 (2)
C2—H2A0.9900C12—H12A0.9800
C2—H2B0.9900C12—H12B0.9800
C3—C41.515 (2)C12—H12C0.9800
C3—H3A0.9900
C1—O1—C4109.15 (13)O1—C4—H4B109.2
N2—N1—C2113.52 (14)C3—C4—H4B109.2
N2—N1—C3121.12 (14)H4A—C4—H4B107.9
C2—N1—C3115.93 (14)C10—C5—C6119.32 (16)
N3—N2—N1113.93 (14)C10—C5—N3115.78 (15)
N2—N3—C5112.31 (14)C6—C5—N3124.83 (14)
C11—N4—C8127.19 (14)C7—C6—C5119.82 (15)
C11—N4—H4N117.5 (12)C7—C6—H6120.1
C8—N4—H4N115.3 (12)C5—C6—H6120.1
O1—C1—C2111.22 (14)C6—C7—C8120.77 (16)
O1—C1—H1A109.4C6—C7—H7119.6
C2—C1—H1A109.4C8—C7—H7119.6
O1—C1—H1B109.4C9—C8—C7119.38 (16)
C2—C1—H1B109.4C9—C8—N4123.00 (15)
H1A—C1—H1B108.0C7—C8—N4117.55 (14)
N1—C2—C1109.14 (14)C10—C9—C8119.79 (15)
N1—C2—H2A109.9C10—C9—H9120.1
C1—C2—H2A109.9C8—C9—H9120.1
N1—C2—H2B109.9C9—C10—C5120.90 (16)
C1—C2—H2B109.9C9—C10—H10119.5
H2A—C2—H2B108.3C5—C10—H10119.5
N1—C3—C4108.78 (14)O2—C11—N4123.37 (15)
N1—C3—H3A109.9O2—C11—C12121.44 (15)
C4—C3—H3A109.9N4—C11—C12115.19 (14)
N1—C3—H3B109.9C11—C12—H12A109.5
C4—C3—H3B109.9C11—C12—H12B109.5
H3A—C3—H3B108.3H12A—C12—H12B109.5
O1—C4—C3111.89 (14)C11—C12—H12C109.5
O1—C4—H4A109.2H12A—C12—H12C109.5
C3—C4—H4A109.2H12B—C12—H12C109.5
C2—N1—N2—N3159.87 (14)N3—C5—C6—C7178.36 (16)
C3—N1—N2—N314.8 (2)C5—C6—C7—C81.3 (3)
N1—N2—N3—C5178.35 (13)C6—C7—C8—C90.5 (2)
C4—O1—C1—C262.57 (18)C6—C7—C8—N4176.59 (16)
N2—N1—C2—C1163.16 (14)C11—N4—C8—C925.5 (3)
C3—N1—C2—C149.87 (19)C11—N4—C8—C7157.45 (16)
O1—C1—C2—N155.31 (19)C7—C8—C9—C100.0 (2)
N2—N1—C3—C4166.58 (14)N4—C8—C9—C10176.97 (16)
C2—N1—C3—C449.15 (19)C8—C9—C10—C50.2 (3)
C1—O1—C4—C362.36 (19)C6—C5—C10—C90.9 (2)
N1—C3—C4—O154.28 (19)N3—C5—C10—C9178.10 (15)
N2—N3—C5—C10170.70 (14)C8—N4—C11—O24.0 (3)
N2—N3—C5—C612.3 (2)C8—N4—C11—C12175.96 (16)
C10—C5—C6—C71.4 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4N···O2i0.903 (17)1.911 (18)2.8115 (18)174.5 (17)
Symmetry code: (i) x, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC12H16N4O2
Mr248.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)90
a, b, c (Å)12.6013 (4), 10.6114 (3), 9.2967 (2)
β (°) 93.874 (2)
V3)1240.29 (6)
Z4
Radiation typeCu Kα
µ (mm1)0.77
Crystal size (mm)0.23 × 0.17 × 0.01
Data collection
DiffractometerBruker Kappa APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.843, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
11437, 2249, 1655
Rint0.053
(sin θ/λ)max1)0.605
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.095, 1.03
No. of reflections2249
No. of parameters168
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.20

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

RI acknowledges Whittier College for the faculty research grant that funded this research. TC thanks Whittier College for summer support. Mr Jonathan Attard is thanked for an initial trial synthesis of the title compound.

References

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First citationChen, B., Flatt, A. K., Jian, H., Hudson, J. L. & Tour, J. M. (2005). Chem. Mater. 17, 4832–4836.  Web of Science CrossRef CAS
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals
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First citationLittle, V. R., Jenkins, H. & Vaughan, K. (2008). J. Chem. Crystallogr. 38, 447–452.  Web of Science CSD CrossRef CAS
First citationSengupta, S., Bhattacharyya, S. & Sadhukhan, S. K. (1998). J. Chem. Soc. Perkin Trans. 1, pp. 275–277.  Web of Science CrossRef
First citationSheldrick, G. (2004). SADABS. University of Göttingen, Germany.
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals

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