6,7-Difluoro-1,2,3,4-tetra-hydro-quin-oxa-line-5,8-dicarbonitrile.

In the title compound, C10H6F2N4, the Car-N bonds are slightly shortened with respect to a standard aniline C-N bond [1.3580 (16) and 1.3618 (16) versus 1.39 Å], thus indicating some π-π conjgation with the electron-acceptor CN groups. The mol-ecule, except for two C atom of the ethyl-ene bridge, is nearly planar, the largest deviation of the other non-H atoms from the mean plane being 0.309 (2) Å. The N-C-C-N torsion angle involving the ethyl-ene bridge is 50.23 (18)°. In the crystal, mol-ecules are connected by pairs of N-H⋯N hydrogen bonds into chains along [21-1].

Related literature

For general background to the synthesis and use of tetra­fluoro­terephthalonitrile and its derivatives, see: Meazza et al. (2007 ▶). For reference structural data on tetra­fluoro­terephthalic acid, see: Orthaber et al. (2010 ▶). For standard bond lengths, see: Allen et al. (1987 ▶). For hydrogen bonding graph-set descriptors, see: Etter (1990 ▶).

Experimental

Crystal data

C10H6F2N4

M = 220.19

Triclinic,

a = 5.2173 (9) Å

b = 8.7011 (15) Å

c = 11.1453 (19) Å

α = 75.545 (2)°

β = 81.854 (2)°

γ = 76.427 (2)°

V = 474.40 (14) Å3

Z = 2

Mo Kα radiation

μ = 0.13 mm−1

T = 293 K

0.28 × 0.24 × 0.16 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ▶) T min = 0.964, T max = 0.980

4155 measured reflections

2141 independent reflections

1816 reflections with I > 2σ(I)

R int = 0.026

Refinement

R[F 2 > 2σ(F 2)] = 0.043

wR(F 2) = 0.140

S = 1.06

2141 reflections

145 parameters

H-atom parameters constrained

Δρmax = 0.29 e Å−3

Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and DIAMOND (Brandenburg, 2005 ▶); software used to prepare material for publication: SHELXTL.

Click here for additional data file.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536813003206/yk2078sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813003206/yk2078Isup2.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536813003206/yk2078Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C10H6F2N4	Z = 2
Mr = 220.19	F(000) = 224
Triclinic, P1	Dx = 1.541 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.2173 (9) Å	Cell parameters from 2503 reflections
b = 8.7011 (15) Å	θ = 2.5–27.6°
c = 11.1453 (19) Å	µ = 0.13 mm−1
α = 75.545 (2)°	T = 293 K
β = 81.854 (2)°	Block, colorless
γ = 76.427 (2)°	0.28 × 0.24 × 0.16 mm
V = 474.40 (14) Å3

Bruker APEXII CCD diffractometer	2141 independent reflections
Radiation source: fine-focus sealed tube	1816 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.026
φ and ω scans	θmax = 27.6°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −6→6
Tmin = 0.964, Tmax = 0.980	k = −11→11
4155 measured reflections	l = −14→13

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140	H-atom parameters constrained
S = 1.06	w = 1/[σ2(Fo2) + (0.0825P)2 + 0.0701P] where P = (Fo2 + 2Fc2)/3
2141 reflections	(Δ/σ)max < 0.001
145 parameters	Δρmax = 0.29 e Å−3
0 restraints	Δρmin = −0.23 e Å−3

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.

	x	y	z	Uiso*/Ueq
C1	0.5584 (3)	0.24423 (15)	0.57193 (12)	0.0414 (3)
C2	−0.1573 (3)	−0.09578 (15)	0.89446 (12)	0.0403 (3)
C3	0.3758 (2)	0.16100 (14)	0.65684 (11)	0.0359 (3)
C4	0.4178 (2)	−0.00938 (14)	0.67660 (11)	0.0382 (3)
C5	0.2446 (3)	−0.09029 (14)	0.75315 (12)	0.0389 (3)
C6	0.0223 (2)	−0.00551 (14)	0.81451 (11)	0.0359 (3)
C7	−0.0247 (2)	0.16328 (14)	0.79859 (11)	0.0348 (3)
C8	0.1573 (2)	0.24965 (14)	0.71567 (11)	0.0355 (3)
C9	−0.2521 (3)	0.41626 (17)	0.85819 (15)	0.0548 (4)
H9A	−0.1510	0.4206	0.9235	0.066*
H9B	−0.4347	0.4681	0.8760	0.066*
C10	−0.1447 (3)	0.50503 (16)	0.73570 (16)	0.0539 (4)
H10A	−0.2651	0.5195	0.6731	0.065*
H10B	−0.1288	0.6115	0.7421	0.065*
F1	0.63601 (16)	−0.08862 (10)	0.61981 (8)	0.0525 (3)
F2	0.28294 (18)	−0.25305 (9)	0.77522 (9)	0.0548 (3)
N1	0.6992 (3)	0.31503 (17)	0.50478 (13)	0.0574 (4)
N2	−0.3029 (3)	−0.16595 (16)	0.95803 (12)	0.0560 (3)
N3	0.1134 (2)	0.41386 (13)	0.69902 (12)	0.0481 (3)
H3	0.2066	0.4607	0.6368	0.058*
N4	−0.2375 (2)	0.24862 (13)	0.85611 (11)	0.0463 (3)
H4	−0.3500	0.2005	0.9065	0.056*

	U11	U22	U33	U12	U13	U23
C1	0.0426 (7)	0.0361 (6)	0.0434 (7)	−0.0099 (5)	0.0025 (5)	−0.0070 (5)
C2	0.0442 (7)	0.0324 (6)	0.0425 (7)	−0.0105 (5)	−0.0031 (5)	−0.0029 (5)
C3	0.0368 (6)	0.0330 (6)	0.0366 (6)	−0.0104 (5)	0.0008 (5)	−0.0046 (5)
C4	0.0385 (6)	0.0328 (6)	0.0413 (6)	−0.0054 (5)	0.0013 (5)	−0.0093 (5)
C5	0.0450 (7)	0.0263 (5)	0.0438 (7)	−0.0075 (5)	−0.0038 (5)	−0.0050 (5)
C6	0.0384 (6)	0.0307 (6)	0.0372 (6)	−0.0106 (5)	−0.0021 (5)	−0.0029 (5)
C7	0.0348 (6)	0.0307 (6)	0.0367 (6)	−0.0080 (4)	−0.0009 (5)	−0.0038 (4)
C8	0.0374 (6)	0.0290 (6)	0.0389 (6)	−0.0091 (4)	−0.0014 (5)	−0.0043 (4)
C9	0.0552 (8)	0.0362 (7)	0.0657 (9)	−0.0042 (6)	0.0124 (7)	−0.0132 (6)
C10	0.0528 (8)	0.0307 (6)	0.0715 (10)	−0.0053 (5)	0.0069 (7)	−0.0091 (6)
F1	0.0486 (5)	0.0416 (4)	0.0609 (5)	−0.0030 (3)	0.0120 (4)	−0.0149 (4)
F2	0.0620 (5)	0.0262 (4)	0.0709 (6)	−0.0087 (3)	0.0058 (4)	−0.0084 (4)
N1	0.0592 (8)	0.0508 (7)	0.0578 (7)	−0.0212 (6)	0.0136 (6)	−0.0053 (6)
N2	0.0555 (7)	0.0487 (7)	0.0587 (7)	−0.0205 (6)	0.0065 (6)	0.0002 (6)
N3	0.0470 (6)	0.0279 (5)	0.0627 (7)	−0.0106 (4)	0.0132 (5)	−0.0051 (5)
N4	0.0420 (6)	0.0344 (5)	0.0564 (7)	−0.0093 (4)	0.0126 (5)	−0.0075 (5)

C1—N1	1.1425 (17)	C7—C8	1.4354 (16)
C1—C3	1.4330 (17)	C8—N3	1.3618 (16)
C2—N2	1.1408 (17)	C9—N4	1.4485 (18)
C2—C6	1.4310 (17)	C9—C10	1.495 (2)
C3—C8	1.3973 (17)	C9—H9A	0.9700
C3—C4	1.4116 (17)	C9—H9B	0.9700
C4—F1	1.3481 (14)	C10—N3	1.4537 (18)
C4—C5	1.3492 (18)	C10—H10A	0.9700
C5—F2	1.3465 (14)	C10—H10B	0.9700
C5—C6	1.4081 (18)	N3—H3	0.8600
C6—C7	1.4007 (16)	N4—H4	0.8599
C7—N4	1.3580 (16)
N1—C1—C3	177.89 (14)	C3—C8—C7	118.45 (11)
N2—C2—C6	179.11 (14)	N4—C9—C10	110.40 (12)
C8—C3—C4	121.41 (11)	N4—C9—H9A	109.6
C8—C3—C1	119.68 (11)	C10—C9—H9A	109.6
C4—C3—C1	118.89 (11)	N4—C9—H9B	109.6
F1—C4—C5	121.20 (11)	C10—C9—H9B	109.6
F1—C4—C3	118.67 (11)	H9A—C9—H9B	108.1
C5—C4—C3	120.12 (11)	N3—C10—C9	109.85 (12)
F2—C5—C4	121.21 (11)	N3—C10—H10A	109.7
F2—C5—C6	118.54 (11)	C9—C10—H10A	109.7
C4—C5—C6	120.23 (11)	N3—C10—H10B	109.7
C7—C6—C5	121.40 (11)	C9—C10—H10B	109.7
C7—C6—C2	120.11 (11)	H10A—C10—H10B	108.2
C5—C6—C2	118.48 (11)	C8—N3—C10	120.46 (11)
N4—C7—C6	122.84 (11)	C8—N3—H3	114.4
N4—C7—C8	118.78 (11)	C10—N3—H3	118.1
C6—C7—C8	118.36 (11)	C7—N4—C9	121.10 (11)
N3—C8—C3	122.59 (11)	C7—N4—H4	121.1
N3—C8—C7	118.94 (11)	C9—N4—H4	116.3
C8—C3—C4—F1	−178.24 (11)	C4—C3—C8—N3	179.46 (12)
C1—C3—C4—F1	3.43 (18)	C1—C3—C8—N3	−2.24 (19)
C1—C3—C4—C5	−177.99 (11)	C4—C3—C8—C7	0.62 (19)
F1—C4—C5—F2	−0.2 (2)	C1—C3—C8—C7	178.93 (10)
C3—C4—C5—F2	−178.78 (11)	N4—C7—C8—N3	1.12 (19)
F1—C4—C5—C6	178.02 (11)	C6—C7—C8—N3	179.76 (11)
C3—C4—C5—C6	−0.5 (2)	N4—C7—C8—C3	180.00 (11)
F2—C5—C6—C7	178.04 (11)	C6—C7—C8—C3	−1.37 (18)
C4—C5—C6—C7	−0.3 (2)	N4—C9—C10—N3	−50.23 (18)
F2—C5—C6—C2	−1.96 (18)	C3—C8—N3—C10	164.48 (13)
C4—C5—C6—C2	179.72 (11)	C7—C8—N3—C10	−16.7 (2)
C5—C6—C7—N4	179.80 (11)	C9—C10—N3—C8	41.7 (2)
C2—C6—C7—N4	−0.20 (19)	C6—C7—N4—C9	167.19 (13)
C5—C6—C7—C8	1.22 (19)	C8—C7—N4—C9	−14.2 (2)
C2—C6—C7—C8	−178.78 (10)	C10—C9—N4—C7	39.5 (2)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···N1i	0.86	2.29	3.075 (2)	152
N4—H4···N2ii	0.86	2.21	3.0358 (19)	160

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯N1i	0.86	2.29	3.075 (2)	152
N4—H4⋯N2ii	0.86	2.21	3.0358 (19)	160

Symmetry codes: (i) ; (ii) .