Propane-1,3-diyl bis­(4-amino­benzoate)

Mol­ecules of the title compound, C₁₇H₁₈N₂O₄, lie on a twofold rotation axis that passes through the central methyl­ene C atom. The mol­ecules adopt a `V' shape and the trimethyl­ene unit assumes a gauche–gauche conformation. The amino N atom shows a nonplanar coordination. Adjacent mol­ecules are connected by N—H...O hydrogen bonds into chains running along [001]. Furthermore, N—H...N hydrogen bonds connect these chains into a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.109
• Data-to-parameter ratio = 9.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.26
PLAT601_ALERT_2_C Structure Contains Solvent Accessible VOIDS of .      38.00 A   3 
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          4

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.49
           From the CIF: _reflns_number_total               1082
           Count of symmetry unique reflns         1086
           Completeness (_total/calc)             99.63%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          3

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

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

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S1. Comment

The chemical is a commercially available chemical that should be compable of condensing with carbonyl compounds to yield Schff bases; its special feature is its trimethylene portion, which assumes a V shape. The C₁₇H₁₈N₂O₄ molecule (Scheme I) lies on a twofold rotation axis that passes through the central methylene carbon atom; this symmetry element relates one 4-aminobenzoate unit to the other. The molecule assumes a V shape and the trimethylene portion assumes a gauche–gauche conformation. The amino nitrogen atom shows non-planar coordination (Fig. 1). Adjacent molecules are connected by N–H···O and N–H···N shydrogen bonds to form a three-dimensional network.

Related literature

For the crystal structure of 1,3-propandiyl-bis(benzoate), see: Pérez & Brisse (1977).

S2. Experimental

The compound was returned unchanged but in a crystalline form in an unsuccessful condensation with o-vanillin in ethanol medium.

S3. Refinement

Carbon-bound H-atoms were placed in calculated positions [C–H 0.95–0.99 Å, U(H) 1.2U(C)] and were included in the refinement in the riding model approximation. The amino H-atoms were located in a difference Fourier map, and were refined isotropically with a distance restraint of N–H 0.86±0.01 Å. 822 Friedel pairs were merged.

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

Fig. 1. Anisotropic displacement ellipsoid plot (Barbour, 2001) of C17H18N2O4 at the 50% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

Propane-1,3-diyl bis(4-aminobenzoate)

Crystal data

C17H18N2O4	F(000) = 332
Mr = 314.33	Dx = 1.242 Mg m^−3
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2y	Cell parameters from 915 reflections
a = 23.725 (5) Å	θ = 2.6–26.8°
b = 4.5109 (9) Å	µ = 0.09 mm^−1
c = 8.2171 (17) Å	T = 100 K
β = 107.173 (3)°	Plate, yellow
V = 840.2 (3) Å^3	0.35 × 0.35 × 0.02 mm
Z = 2

Data collection

Bruker SMART APEX diffractometer	788 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.090
Graphite monochromator	θmax = 27.5°, θmin = 1.8°
ω scans	h = −30→29
3936 measured reflections	k = −5→5
1082 independent reflections	l = −10→10

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.109	H atoms treated by a mixture of independent and constrained refinement
S = 0.96	w = 1/[σ^2(Fo^2) + (0.0523P)^2] where P = (Fo^2 + 2Fc^2)/3
1082 reflections	(Δ/σ)max = 0.001
113 parameters	Δρmax = 0.24 e Å^−3
3 restraints	Δρmin = −0.24 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	0.42724 (7)	0.4987 (4)	0.0488 (2)	0.0262 (5)
O2	0.35969 (8)	0.7580 (5)	−0.1476 (2)	0.0304 (5)
N1	0.29701 (11)	1.0783 (6)	0.5367 (3)	0.0298 (6)
C1	0.5000	0.1862 (10)	0.0000	0.0279 (10)
H1A	0.5095	0.0569	−0.0857	0.033*	0.50
H1B	0.4905	0.0569	0.0857	0.033*	0.50
C2	0.44676 (11)	0.3705 (7)	−0.0862 (3)	0.0263 (7)
H2A	0.4572	0.5279	−0.1562	0.032*
H2B	0.4153	0.2454	−0.1609	0.032*
C3	0.38135 (11)	0.6876 (7)	0.0010 (3)	0.0244 (7)
C4	0.36179 (11)	0.7924 (7)	0.1432 (3)	0.0228 (6)
C5	0.31600 (11)	0.9969 (7)	0.1134 (3)	0.0260 (7)
H5	0.2991	1.0721	0.0016	0.031*
C6	0.29486 (12)	1.0917 (7)	0.2423 (3)	0.0286 (7)
H6	0.2631	1.2289	0.2187	0.034*
C7	0.31969 (11)	0.9879 (7)	0.4094 (3)	0.0252 (7)
C8	0.36569 (11)	0.7851 (8)	0.4393 (3)	0.0295 (7)
H8	0.3830	0.7123	0.5514	0.035*
C9	0.38646 (11)	0.6885 (8)	0.3103 (3)	0.0282 (7)
H9	0.4179	0.5495	0.3338	0.034*
H11	0.3137 (17)	1.032 (12)	0.641 (2)	0.098 (16)*
H12	0.2748 (10)	1.233 (4)	0.519 (3)	0.025 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0204 (9)	0.0351 (12)	0.0206 (9)	0.0041 (10)	0.0021 (7)	0.0031 (9)
O2	0.0239 (10)	0.0453 (13)	0.0165 (9)	0.0042 (10)	−0.0024 (7)	0.0029 (10)
N1	0.0272 (14)	0.0364 (17)	0.0227 (13)	0.0056 (12)	0.0025 (11)	0.0016 (12)
C1	0.021 (2)	0.030 (3)	0.029 (2)	0.000	0.0034 (16)	0.000
C2	0.0205 (13)	0.0329 (17)	0.0243 (14)	−0.0040 (13)	0.0046 (11)	−0.0024 (13)
C3	0.0172 (13)	0.0302 (17)	0.0224 (13)	−0.0048 (13)	0.0005 (11)	0.0009 (13)
C4	0.0163 (12)	0.0304 (17)	0.0183 (12)	−0.0025 (12)	−0.0001 (10)	0.0023 (11)
C5	0.0190 (13)	0.0322 (17)	0.0193 (13)	−0.0007 (14)	−0.0058 (11)	0.0043 (13)
C6	0.0191 (14)	0.0368 (19)	0.0236 (14)	0.0029 (13)	−0.0031 (12)	0.0038 (13)
C7	0.0186 (13)	0.0335 (18)	0.0202 (13)	−0.0060 (14)	0.0006 (10)	0.0005 (13)
C8	0.0218 (14)	0.043 (2)	0.0179 (13)	0.0039 (14)	−0.0026 (11)	0.0090 (14)
C9	0.0181 (14)	0.0397 (19)	0.0237 (14)	0.0030 (14)	0.0012 (11)	0.0050 (14)

Geometric parameters (Å, º)

O1—C3	1.347 (3)	C3—C4	1.457 (4)
O1—C2	1.444 (3)	C4—C5	1.391 (4)
O2—C3	1.219 (3)	C4—C9	1.405 (3)
N1—C7	1.372 (3)	C5—C6	1.368 (4)
N1—H11	0.858 (10)	C5—H5	0.9500
N1—H12	0.861 (10)	C6—C7	1.405 (4)
C1—C2	1.503 (4)	C6—H6	0.9500
C1—C2^i	1.503 (4)	C7—C8	1.389 (4)
C1—H1A	0.9900	C8—C9	1.365 (4)
C1—H1B	0.9900	C8—H8	0.9500
C2—H2A	0.9900	C9—H9	0.9500
C2—H2B	0.9900
C3—O1—C2	116.39 (19)	C5—C4—C9	118.1 (2)
C7—N1—H11	121 (3)	C5—C4—C3	119.4 (2)
C7—N1—H12	118.1 (19)	C9—C4—C3	122.4 (2)
H11—N1—H12	116 (4)	C6—C5—C4	121.1 (2)
C2—C1—C2^i	112.9 (4)	C6—C5—H5	119.4
C2—C1—H1A	109.0	C4—C5—H5	119.4
C2^i—C1—H1A	109.0	C5—C6—C7	120.6 (3)
C2—C1—H1B	109.0	C5—C6—H6	119.7
C2^i—C1—H1B	109.0	C7—C6—H6	119.7
H1A—C1—H1B	107.8	N1—C7—C8	121.7 (2)
O1—C2—C1	105.94 (18)	N1—C7—C6	120.0 (3)
O1—C2—H2A	110.5	C8—C7—C6	118.2 (2)
C1—C2—H2A	110.5	C9—C8—C7	121.2 (3)
O1—C2—H2B	110.5	C9—C8—H8	119.4
C1—C2—H2B	110.5	C7—C8—H8	119.4
H2A—C2—H2B	108.7	C8—C9—C4	120.7 (3)
O2—C3—O1	121.5 (2)	C8—C9—H9	119.7
O2—C3—C4	125.4 (3)	C4—C9—H9	119.7
O1—C3—C4	113.1 (2)
C3—O1—C2—C1	176.5 (2)	C3—C4—C5—C6	177.4 (3)
C2^i—C1—C2—O1	−71.92 (18)	C4—C5—C6—C7	1.1 (4)
C2—O1—C3—O2	−3.8 (4)	C5—C6—C7—N1	−178.2 (3)
C2—O1—C3—C4	176.2 (2)	C5—C6—C7—C8	−0.6 (4)
O2—C3—C4—C5	−2.2 (4)	N1—C7—C8—C9	177.6 (3)
O1—C3—C4—C5	177.8 (3)	C6—C7—C8—C9	0.1 (5)
O2—C3—C4—C9	176.1 (3)	C7—C8—C9—C4	0.1 (5)
O1—C3—C4—C9	−4.0 (4)	C5—C4—C9—C8	0.3 (4)
C9—C4—C5—C6	−0.9 (4)	C3—C4—C9—C8	−177.9 (3)

Symmetry code: (i) −x+1, y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11···O2^ii	0.86 (1)	2.15 (2)	2.958 (3)	157 (5)
N1—H12···N1^iii	0.86 (1)	2.25 (1)	3.104 (3)	169 (2)

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