A tetrakis­(secondary amide) derivative of norborna­diene: 7-iso­propyl­idene-N,N′,N′′,N′′′-tetra­phenyl­norborna-2,5-diene-2,3,5,6-tetracarbox­amide

The title compound, C₃₈H₃₂N₄O₄, displays crystallographic twofold symmetry. The four amide groups are arranged such that four intramolecular N—H...O hydrogen bonds are formed. The mol­ecules are linked into chains by short C—H...O interactions involving the methine H atoms.

Key indicators

• Single-crystal X-ray study
• T = 143 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.043
• wR factor = 0.119
• Data-to-parameter ratio = 17.5

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

In pursuance of our research towards a photo-switchable ion carrier based on the norbornadiene-quadricyclane isomerization (Herges & Reif, 1994, 1996; Herges et al., 1999; Starck et al., 1998), we have synthesized several norbornadiene and quadricyclane tetra-amides. The tertiary derivatives are able to form stable complexes with alkali metal cations (Winkler et al., 2003), but the secondary amides cannot. Here we present the structure of the title compound, (I), the first of a brief series of such structures.

The molecule of (I) (Fig. 1) possesses crystallographic twofold symmetry, with atoms C7 and C8 lying on the twofold axis. Molecular dimensions (Table 1) may be considered normal, e.g. the distorted bond angles of the norbornadiene system. The four amide groups are arranged such that four intramolecular hydrogen bonds (Table 2) of the type N—H···O are formed, each in a ring of graph set R₁¹(7). This closed system is presumably responsible for the inability to form metal complexes. The hydrogen-bonding framework of all secondary amides presented in this series remains intact in solution in chloroform, whereas the hydrogen bonds are broken in dimethyl sulfoxide (Winkler, 2002).

The amide groups, which are each planar (r.m.s. deviation 0.043 Å for C2/C11/N1/C12/O1 and 0.006 Å for C3/C18/N2/C19/O2) subtend an angle of 43.32 (3)°. The phenyl rings are very approximately parallel to the plane defined by atoms C2, C3, C2ⁱ and C3ⁱ, with interplanar angles of 27.09 (3) and 26.50 (3)° [symmetry code: (i) 1 − x, y, −z + 3/2].

The molecules are connected to form chains parallel to the z axis by intermolecular hydrogen bonds C1—H1···O1 involving the methine H atoms (Fig. 2); ring systems of graph set R²₂(10) are thereby formed.

S2. Experimental

The title compound was prepared according to Winkler (2002) and recrystallized from a solution in dichloromethane/methanol by evaporation.

S3. Refinement

H atoms bonded to N atoms were refined freely. Methyl H atoms were located in difference syntheses, idealized (C—H 0.98 Å and H—C—H 109.5°) and refined on the basis of rigid groups allowed to rotate but not tip. H atoms were included using a riding model with fixed C—H bond lengths of 1.00 (methine) or 0.95 Å (aromatic); U_iso(H) values were fixed at 1.2U_eq of the parent atom.

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The molecule of the title compound in the crystal. Ellipsoids represent 50% probability levels. H-atom radii are arbitrary. Only the asymmetric unit is numbered. Hydrogen bonds are indicated by dashed lines.
	Fig. 2. Packing diagram of the title compound, viewed perpendicular to the yz plane. H atoms not involved in hydrogen bonds have been omitted. Intermolecular hydrogen bonds are shown as thick dashed lines and intramolecular hydrogen bonds have been omitted.

7-Isopropylidenenorborna-2,5-diene-2,3,5,6-tetracarboxylic acid tetrakis(phenylamide)

Crystal data

C38H32N4O4	F(000) = 1280
Mr = 608.68	Dx = 1.343 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 26.8424 (16) Å	Cell parameters from 5762 reflections
b = 7.8024 (6) Å	θ = 2.7–28.6°
c = 14.8652 (10) Å	µ = 0.09 mm^−1
β = 104.708 (3)°	T = 143 K
V = 3011.3 (4) Å^3	Tablet, yellow
Z = 4	0.46 × 0.38 × 0.19 mm

Data collection

Bruker SMART 1000 CCD diffractometer	3255 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.043
Graphite monochromator	θmax = 28.5°, θmin = 1.6°
Detector resolution: 8.192 pixels mm^-1	h = −36→36
ω scans	k = −10→10
22552 measured reflections	l = −19→19
3818 independent reflections

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) = 0.119	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0624P)^2 + 1.8321P] where P = (Fo^2 + 2Fc^2)/3
3818 reflections	(Δ/σ)max = 0.001
218 parameters	Δρmax = 0.35 e Å^−3
0 restraints	Δρmin = −0.19 e Å^−3

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

5.6520 (0.0166) x + 6.9466 (0.0023) y − 6.5995 (0.0085) z = 1.0248 (0.0060)

* 0.0036 (0.0009) C12 * −0.0011 (0.0010) C13 * −0.0004 (0.0011) C14 * −0.0007 (0.0012) C15 * 0.0033 (0.0011) C16 * −0.0047 (0.0010) C17

Rms deviation of fitted atoms = 0.0028

− 0.0000 (0.0001) x + 7.8024 (0.0006) y + 0.0000 (0.0001) z = 3.7068 (0.0007)

Angle to previous plane (with approximate e.s.d.) = 27.09 (0.03)

* 0.0018 (0.0007) C2 * −0.0018 (0.0007) C3 * 0.0018 (0.0007) C2_$1 * −0.0018 (0.0007) C3_$1

Rms deviation of fitted atoms = 0.0018

− 5.6213 (0.0157) x + 6.9826 (0.0020) y + 6.4554 (0.0078) z = 5.6528 (0.0090)

Angle to previous plane (with approximate e.s.d.) = 26.50 (0.03)

* 0.0043 (0.0009) C19 * −0.0053 (0.0009) C20 * 0.0009 (0.0010) C21 * 0.0046 (0.0011) C22 * −0.0057 (0.0011) C23 * 0.0012 (0.0010) C24

Rms deviation of fitted atoms = 0.0041

=============================================================================

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

0.2191 (0.0125) x − 7.0791 (0.0017) y + 6.0137 (0.0072) z = 0.7974 (0.0048)

* −0.0418 (0.0005) C2 * 0.0263 (0.0009) C11 * 0.0655 (0.0008) N1 * −0.0516 (0.0006) C12 * 0.0015 (0.0003) O1

Rms deviation of fitted atoms = 0.0434

− 11.0358 (0.0134) x + 6.9429 (0.0017) y + 4.3964 (0.0059) z = 1.6570 (0.0082)

Angle to previous plane (with approximate e.s.d.) = 43.32 (0.03)

* 0.0057 (0.0005) C3 * −0.0016 (0.0009) C18 * −0.0110 (0.0008) N2 * 0.0079 (0.0005) C19 * −0.0010 (0.0004) O2

Rms deviation of fitted atoms = 0.0066

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.46797 (3)	0.35143 (11)	0.52949 (5)	0.02332 (18)
O2	0.36315 (3)	0.35672 (13)	0.72491 (6)	0.0296 (2)
N1	0.38661 (4)	0.36042 (13)	0.55369 (6)	0.0228 (2)
N2	0.41657 (4)	0.34689 (12)	0.87225 (6)	0.0210 (2)
C1	0.50972 (4)	0.57821 (13)	0.68071 (7)	0.0187 (2)
H1	0.5178	0.6228	0.6229	0.022*
C2	0.45922 (4)	0.47532 (13)	0.66846 (7)	0.0187 (2)
C3	0.44755 (4)	0.47485 (13)	0.75173 (7)	0.0186 (2)
C7	0.5000	0.71112 (19)	0.7500	0.0197 (3)
C8	0.5000	0.8815 (2)	0.7500	0.0260 (3)
C9	0.51408 (5)	0.98602 (17)	0.67509 (10)	0.0355 (3)
H9A	0.5205	0.9094	0.6270	0.043*
H9B	0.5452	1.0528	0.7021	0.043*
H9C	0.4857	1.0640	0.6474	0.043*
C11	0.43792 (4)	0.38790 (13)	0.57765 (7)	0.0192 (2)
C12	0.35563 (4)	0.30243 (15)	0.46707 (7)	0.0229 (2)
C13	0.30257 (5)	0.32864 (18)	0.44993 (9)	0.0308 (3)
H13	0.2887	0.3827	0.4955	0.037*
C14	0.27008 (5)	0.2755 (2)	0.36612 (10)	0.0385 (3)
H14	0.2340	0.2938	0.3543	0.046*
C15	0.29029 (5)	0.1958 (2)	0.29948 (10)	0.0420 (3)
H15	0.2681	0.1591	0.2423	0.050*
C16	0.34278 (5)	0.1701 (2)	0.31684 (9)	0.0400 (3)
H16	0.3565	0.1166	0.2710	0.048*
C17	0.37573 (5)	0.22157 (18)	0.40043 (8)	0.0308 (3)
H17	0.4117	0.2018	0.4121	0.037*
C18	0.40481 (4)	0.38759 (14)	0.78059 (7)	0.0204 (2)
C19	0.38458 (4)	0.26695 (14)	0.92247 (8)	0.0224 (2)
C20	0.40866 (5)	0.20366 (17)	1.01043 (8)	0.0286 (3)
H20	0.4450	0.2108	1.0327	0.034*
C21	0.37974 (5)	0.13022 (19)	1.06563 (9)	0.0355 (3)
H21	0.3964	0.0882	1.1258	0.043*
C22	0.32671 (6)	0.11802 (19)	1.03323 (10)	0.0364 (3)
H22	0.3068	0.0684	1.0710	0.044*
C23	0.30298 (5)	0.1786 (2)	0.94543 (10)	0.0385 (3)
H23	0.2667	0.1686	0.9228	0.046*
C24	0.33141 (5)	0.25421 (19)	0.88948 (9)	0.0330 (3)
H24	0.3146	0.2965	0.8295	0.040*
H02	0.4486 (6)	0.3646 (19)	0.9054 (11)	0.030 (4)*
H01	0.3711 (6)	0.384 (2)	0.5986 (11)	0.037 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0206 (4)	0.0294 (4)	0.0208 (4)	−0.0016 (3)	0.0068 (3)	−0.0005 (3)
O2	0.0198 (4)	0.0450 (5)	0.0239 (4)	−0.0088 (4)	0.0051 (3)	−0.0015 (4)
N1	0.0186 (4)	0.0292 (5)	0.0205 (4)	−0.0021 (4)	0.0050 (3)	−0.0023 (4)
N2	0.0181 (4)	0.0242 (5)	0.0215 (4)	−0.0020 (4)	0.0067 (3)	−0.0008 (3)
C1	0.0172 (5)	0.0178 (5)	0.0213 (5)	0.0001 (4)	0.0055 (4)	0.0016 (4)
C2	0.0155 (4)	0.0186 (5)	0.0216 (5)	0.0000 (4)	0.0041 (4)	0.0016 (4)
C3	0.0158 (4)	0.0177 (5)	0.0219 (5)	0.0008 (4)	0.0042 (4)	−0.0001 (4)
C7	0.0154 (6)	0.0201 (7)	0.0239 (7)	0.000	0.0055 (5)	0.000
C8	0.0219 (7)	0.0202 (7)	0.0368 (9)	0.000	0.0093 (6)	0.000
C9	0.0372 (7)	0.0217 (6)	0.0510 (8)	−0.0006 (5)	0.0174 (6)	0.0074 (5)
C11	0.0197 (5)	0.0190 (5)	0.0184 (5)	−0.0004 (4)	0.0040 (4)	0.0032 (4)
C12	0.0208 (5)	0.0251 (5)	0.0216 (5)	−0.0032 (4)	0.0031 (4)	0.0012 (4)
C13	0.0233 (6)	0.0360 (7)	0.0314 (6)	0.0017 (5)	0.0038 (5)	−0.0043 (5)
C14	0.0225 (6)	0.0494 (8)	0.0378 (7)	0.0037 (6)	−0.0027 (5)	−0.0055 (6)
C15	0.0330 (7)	0.0571 (9)	0.0290 (6)	−0.0014 (6)	−0.0049 (5)	−0.0090 (6)
C16	0.0349 (7)	0.0572 (9)	0.0271 (6)	−0.0039 (6)	0.0066 (5)	−0.0121 (6)
C17	0.0233 (6)	0.0416 (7)	0.0271 (6)	−0.0039 (5)	0.0058 (4)	−0.0059 (5)
C18	0.0195 (5)	0.0213 (5)	0.0219 (5)	−0.0006 (4)	0.0076 (4)	−0.0019 (4)
C19	0.0249 (5)	0.0217 (5)	0.0234 (5)	−0.0026 (4)	0.0112 (4)	−0.0025 (4)
C20	0.0280 (6)	0.0336 (6)	0.0242 (5)	−0.0094 (5)	0.0065 (4)	−0.0009 (5)
C21	0.0397 (7)	0.0428 (8)	0.0249 (6)	−0.0113 (6)	0.0098 (5)	0.0036 (5)
C22	0.0378 (7)	0.0426 (7)	0.0346 (7)	−0.0089 (6)	0.0199 (5)	0.0022 (6)
C23	0.0251 (6)	0.0531 (9)	0.0410 (7)	−0.0033 (6)	0.0153 (5)	0.0056 (6)
C24	0.0236 (6)	0.0467 (8)	0.0310 (6)	0.0012 (5)	0.0111 (5)	0.0067 (6)

Geometric parameters (Å, º)

O1—C11	1.2399 (13)	C12—C13	1.3966 (16)
O2—C18	1.2343 (14)	C13—C14	1.3903 (18)
N1—C11	1.3493 (14)	C13—H13	0.9500
N1—C12	1.4180 (14)	C14—C15	1.392 (2)
N1—H01	0.891 (17)	C14—H14	0.9500
N2—C18	1.3560 (14)	C15—C16	1.381 (2)
N2—C19	1.4175 (13)	C15—H15	0.9500
N2—H02	0.887 (16)	C16—C17	1.3890 (17)
C1—C7	1.5300 (14)	C16—H16	0.9500
C1—C3^i	1.5457 (14)	C17—H17	0.9500
C1—C2	1.5459 (14)	C19—C24	1.3900 (17)
C1—H1	1.0000	C19—C20	1.3936 (16)
C2—C3	1.3518 (14)	C20—C21	1.3885 (16)
C2—C11	1.4907 (14)	C20—H20	0.9500
C3—C18	1.4879 (14)	C21—C22	1.385 (2)
C7—C8	1.329 (2)	C21—H21	0.9500
C8—C9	1.5039 (15)	C22—C23	1.382 (2)
C9—H9A	0.9800	C22—H22	0.9500
C9—H9B	0.9800	C23—C24	1.3944 (17)
C9—H9C	0.9800	C23—H23	0.9500
C12—C17	1.3934 (16)	C24—H24	0.9500
C11—N1—C12	127.91 (9)	C14—C13—H13	120.0
C11—N1—H01	114.1 (11)	C12—C13—H13	120.0
C12—N1—H01	118.0 (11)	C13—C14—C15	120.12 (12)
C18—N2—C19	127.93 (10)	C13—C14—H14	119.9
C18—N2—H02	117.9 (10)	C15—C14—H14	119.9
C19—N2—H02	114.1 (10)	C16—C15—C14	119.70 (12)
C7—C1—C3^i	98.13 (7)	C16—C15—H15	120.1
C7—C1—C2	97.87 (7)	C14—C15—H15	120.1
C3^i—C1—C2	106.82 (8)	C15—C16—C17	120.86 (13)
C7—C1—H1	117.0	C15—C16—H16	119.6
C3^i—C1—H1	117.0	C17—C16—H16	119.6
C2—C1—H1	117.0	C16—C17—C12	119.56 (12)
C3—C2—C11	134.68 (10)	C16—C17—H17	120.2
C3—C2—C1	107.08 (9)	C12—C17—H17	120.2
C11—C2—C1	117.87 (9)	O2—C18—N2	124.63 (10)
C2—C3—C18	129.80 (10)	O2—C18—C3	121.97 (10)
C2—C3—C1^i	106.70 (9)	N2—C18—C3	113.39 (9)
C18—C3—C1^i	123.41 (9)	C24—C19—C20	119.72 (10)
C8—C7—C1	132.67 (6)	C24—C19—N2	123.42 (10)
C1—C7—C1^i	94.66 (11)	C20—C19—N2	116.83 (10)
C7—C8—C9	122.84 (7)	C21—C20—C19	120.33 (11)
C9—C8—C9^i	114.32 (15)	C21—C20—H20	119.8
C8—C9—H9A	109.5	C19—C20—H20	119.8
C8—C9—H9B	109.5	C22—C21—C20	120.15 (12)
H9A—C9—H9B	109.5	C22—C21—H21	119.9
C8—C9—H9C	109.5	C20—C21—H21	119.9
H9A—C9—H9C	109.5	C23—C22—C21	119.43 (12)
H9B—C9—H9C	109.5	C23—C22—H22	120.3
O1—C11—N1	125.54 (10)	C21—C22—H22	120.3
O1—C11—C2	118.14 (9)	C22—C23—C24	121.14 (12)
N1—C11—C2	116.28 (9)	C22—C23—H23	119.4
C17—C12—C13	119.84 (11)	C24—C23—H23	119.4
C17—C12—N1	123.12 (10)	C19—C24—C23	119.22 (12)
C13—C12—N1	117.05 (10)	C19—C24—H24	120.4
C14—C13—C12	119.90 (12)	C23—C24—H24	120.4
C7—C1—C2—C3	−35.22 (10)	C17—C12—C13—C14	−0.6 (2)
C3^i—C1—C2—C3	65.80 (10)	N1—C12—C13—C14	179.67 (12)
C7—C1—C2—C11	150.74 (9)	C12—C13—C14—C15	0.3 (2)
C3^i—C1—C2—C11	−108.25 (10)	C13—C14—C15—C16	−0.2 (2)
C11—C2—C3—C18	−3.9 (2)	C14—C15—C16—C17	0.6 (3)
C1—C2—C3—C18	−176.45 (10)	C15—C16—C17—C12	−1.0 (2)
C11—C2—C3—C1^i	172.81 (11)	C13—C12—C17—C16	1.0 (2)
C1—C2—C3—C1^i	0.21 (10)	N1—C12—C17—C16	−179.35 (13)
C3^i—C1—C7—C8	125.81 (5)	C19—N2—C18—O2	−1.51 (19)
C2—C1—C7—C8	−125.84 (5)	C19—N2—C18—C3	178.59 (10)
C3^i—C1—C7—C1^i	−54.19 (5)	C2—C3—C18—O2	−28.73 (18)
C2—C1—C7—C1^i	54.16 (5)	C1^i—C3—C18—O2	155.10 (11)
C1—C7—C8—C9	−3.85 (8)	C2—C3—C18—N2	151.17 (11)
C1^i—C7—C8—C9	176.15 (8)	C1^i—C3—C18—N2	−25.00 (14)
C1—C7—C8—C9^i	176.15 (9)	C18—N2—C19—C24	−16.11 (18)
C1^i—C7—C8—C9^i	−3.85 (9)	C18—N2—C19—C20	165.85 (11)
C12—N1—C11—O1	−7.10 (19)	C24—C19—C20—C21	−0.89 (19)
C12—N1—C11—C2	170.58 (10)	N2—C19—C20—C21	177.22 (11)
C3—C2—C11—O1	−148.12 (12)	C19—C20—C21—C22	0.6 (2)
C1—C2—C11—O1	23.86 (14)	C20—C21—C22—C23	0.4 (2)
C3—C2—C11—N1	34.02 (17)	C21—C22—C23—C24	−1.0 (2)
C1—C2—C11—N1	−154.00 (9)	C20—C19—C24—C23	0.3 (2)
C11—N1—C12—C17	17.68 (19)	N2—C19—C24—C23	−177.71 (12)
C11—N1—C12—C13	−162.64 (12)	C22—C23—C24—C19	0.7 (2)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H01···O2	0.891 (17)	1.955 (17)	2.7729 (13)	152.0 (15)
N2—H02···O1^i	0.887 (16)	2.205 (16)	3.0726 (12)	166.0 (14)
C1—H1···O1^ii	1.00	2.40	3.3725 (13)	164

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