5,8-Bis­(tri­methyl­silyl­ethynyl)­quinoline

The title compound, C₁₉H₂₃NSi₂, is a TMS-protected rigid-rod di-yne. It is useful as a model compound for organometallic species of which it is a precursor and, like them, exhibits π-conjugation through the heteroaromatic linker unit in the backbone. The mol­ecule is pseudo-linear, with a planar central quinoline group. Two C—H...N short intermolecular contacts are found, with C...N distances of 3.483 (5) and 3.671 (6) Å. An intermolecular contact between an aromatic H atom and the C[triple bond]C triple bond is also observed.

Key indicators

• Single-crystal X-ray study
• T = 180 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.083
• wR factor = 0.225
• Data-to-parameter ratio = 15.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level A:



DIFF_020  Alert A _diffrn_standards_interval_count and
          _diffrn_standards_interval_time are missing. Number of measurements
          between standards or time (min) between standards.

DIFF_022  Alert A _diffrn_standards_decay_% is missing
          Percentage decrease in standards intensity.


 Alert Level B:



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           25.18
         From the CIF: _reflns_number_total               3166
         TEST2: Reflns within _diffrn_reflns_theta_max
         Count of symmetry unique reflns         3526
         Completeness (_total/calc)             89.79%
          Alert B: < 90% complete (theta max?)

Author response: The data was collected on a one-circle phi diffractometer with two different orientations of the crystal. Despite this attempt to cover all of reciprocal space only just under 90% could be accessed to a 2\q~max~ of 50.0\%.

 Alert Level C:



PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(5)   -   C(10)  =       1.45 Ang.

PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(8)   -   C(15)  =       1.44 Ang.


 2 Alert Level A = Potentially serious problem

 1 Alert Level B = Potential problem

 2 Alert Level C = Please check

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Computing details

Data collection: R-AXIS IIc Control Software (Rigaku/MSC, 1997); cell refinement: HKL SCALEPACK (Otwinowski & Minor, 1997); data reduction: HKL DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

(I)

Crystal data

C19H23NSi2	F(000) = 688
Mr = 321.56	Dx = 1.091 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.334 (2) Å	Cell parameters from 4490 reflections
b = 10.604 (2) Å	θ = 3.8–25.2°
c = 12.465 (2) Å	µ = 0.18 mm^−1
β = 104.96 (1)°	T = 180 K
V = 1958.1 (5) Å^3	Block, colourless
Z = 4	0.3 × 0.3 × 0.25 mm

Data collection

Rigaku R-AXIS IIc diffractometer	Rint = 0.067
φ scans	θmax = 25.2°, θmin = 3.8°
5136 measured reflections	h = −18→17
3166 independent reflections	k = −12→0
2003 reflections with I > 2σ(I)	l = 0→14

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.083	w = 1/[σ^2(Fo^2) + (0.1197P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.225	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 0.47 e Å^−3
3166 reflections	Δρmin = −0.36 e Å^−3
205 parameters

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.

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

	x	y	z	Uiso*/Ueq
Si1	0.74685 (7)	−0.24344 (10)	−0.28418 (9)	0.0433 (4)
Si2	1.38795 (7)	−0.23895 (11)	0.47410 (10)	0.0466 (4)
N1	1.0759 (2)	−0.0595 (3)	0.2498 (3)	0.0444 (8)
C1	1.0084 (3)	0.0204 (4)	0.2346 (3)	0.0473 (10)
H1	1.0109	0.083	0.2898	0.057*
C2	0.9329 (3)	0.0199 (4)	0.1425 (3)	0.0488 (10)
H2	0.8871	0.082	0.1352	0.059*
C3	0.9265 (3)	−0.0713 (4)	0.0640 (3)	0.0414 (9)
H3	0.8758	−0.0739	0.0014	0.05*
C4	0.9958 (2)	−0.1619 (4)	0.0762 (3)	0.0394 (9)
C5	0.9953 (3)	−0.2582 (3)	−0.0029 (3)	0.0382 (9)
C6	1.0666 (3)	−0.3421 (4)	0.0132 (3)	0.0513 (11)
H6	1.0659	−0.4068	−0.0397	0.062*
C7	1.1397 (3)	−0.3321 (4)	0.1071 (4)	0.0523 (11)
H7	1.1883	−0.3901	0.1164	0.063*
C8	1.1430 (2)	−0.2413 (3)	0.1855 (3)	0.0396 (9)
C9	1.0710 (2)	−0.1522 (3)	0.1717 (3)	0.0395 (9)
C10	0.9196 (3)	−0.2652 (4)	−0.0999 (3)	0.0444 (10)
C11	0.8533 (3)	−0.2619 (4)	−0.1773 (3)	0.0435 (10)
C12	0.6786 (4)	−0.1285 (5)	−0.2296 (5)	0.0807 (16)
H12A	0.619	−0.1203	−0.2818	0.121*
H12B	0.709	−0.0464	−0.2202	0.121*
H12C	0.6717	−0.1578	−0.1576	0.121*
C13	0.6896 (4)	−0.3981 (5)	−0.3067 (6)	0.093 (2)
H13A	0.6367	−0.3927	−0.3705	0.139*
H13B	0.6704	−0.4218	−0.2403	0.139*
H13C	0.7314	−0.4619	−0.3213	0.139*
C14	0.7689 (3)	−0.1758 (5)	−0.4114 (4)	0.0624 (13)
H14A	0.7118	−0.1667	−0.4685	0.094*
H14B	0.8092	−0.2319	−0.4387	0.094*
H14C	0.7973	−0.0929	−0.3945	0.094*
C15	1.2192 (3)	−0.2345 (4)	0.2817 (3)	0.0448 (10)
C16	1.2846 (3)	−0.2355 (4)	0.3601 (4)	0.0501 (11)
C17	1.3996 (3)	−0.0863 (5)	0.5491 (4)	0.0737 (15)
H17A	1.4563	−0.0855	0.6075	0.111*
H17B	1.3488	−0.0755	0.5825	0.111*
H17C	1.3997	−0.0173	0.4968	0.111*
C18	1.3794 (4)	−0.3685 (5)	0.5705 (4)	0.0848 (17)
H18A	1.4311	−0.365	0.6359	0.127*
H18B	1.3792	−0.4497	0.5329	0.127*
H18C	1.3233	−0.3595	0.5938	0.127*
C19	1.4825 (3)	−0.2640 (5)	0.4100 (5)	0.0753 (16)
H19A	1.5394	−0.2675	0.4682	0.113*
H19B	1.4848	−0.1941	0.3593	0.113*
H19C	1.4736	−0.3435	0.3686	0.113*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Si1	0.0398 (7)	0.0476 (7)	0.0382 (7)	0.0038 (5)	0.0022 (5)	−0.0031 (5)
Si2	0.0392 (7)	0.0514 (7)	0.0419 (7)	0.0006 (5)	−0.0026 (5)	0.0039 (5)
N1	0.055 (2)	0.0413 (18)	0.0376 (19)	−0.0084 (16)	0.0124 (15)	−0.0021 (15)
C1	0.052 (2)	0.049 (2)	0.040 (2)	0.001 (2)	0.0105 (19)	−0.0104 (19)
C2	0.050 (2)	0.048 (2)	0.049 (3)	0.0010 (19)	0.0134 (19)	0.006 (2)
C3	0.045 (2)	0.044 (2)	0.035 (2)	−0.0049 (17)	0.0102 (16)	0.0041 (17)
C4	0.044 (2)	0.042 (2)	0.032 (2)	−0.0054 (17)	0.0088 (16)	0.0051 (17)
C5	0.040 (2)	0.042 (2)	0.031 (2)	−0.0009 (16)	0.0058 (15)	0.0025 (17)
C6	0.056 (3)	0.057 (3)	0.036 (2)	−0.001 (2)	0.0053 (19)	−0.0046 (19)
C7	0.044 (2)	0.061 (3)	0.050 (3)	0.005 (2)	0.0077 (19)	−0.002 (2)
C8	0.035 (2)	0.048 (2)	0.033 (2)	−0.0044 (16)	0.0039 (16)	0.0031 (18)
C9	0.045 (2)	0.041 (2)	0.033 (2)	−0.0053 (17)	0.0099 (16)	0.0047 (17)
C10	0.044 (2)	0.053 (2)	0.034 (2)	−0.0061 (18)	0.0062 (18)	0.0004 (19)
C11	0.044 (2)	0.048 (2)	0.038 (2)	0.0033 (17)	0.0098 (18)	−0.0040 (18)
C12	0.086 (4)	0.090 (4)	0.075 (4)	0.029 (3)	0.037 (3)	0.009 (3)
C13	0.070 (3)	0.061 (3)	0.118 (5)	−0.012 (3)	−0.029 (3)	0.012 (3)
C14	0.058 (3)	0.085 (3)	0.040 (3)	0.018 (2)	0.007 (2)	0.003 (2)
C15	0.037 (2)	0.050 (2)	0.044 (2)	−0.0025 (17)	0.0047 (18)	0.0018 (19)
C16	0.041 (2)	0.053 (3)	0.052 (3)	−0.0024 (18)	0.004 (2)	0.006 (2)
C17	0.061 (3)	0.070 (3)	0.077 (4)	0.001 (2)	−0.006 (3)	−0.018 (3)
C18	0.104 (4)	0.080 (4)	0.061 (3)	0.000 (3)	0.004 (3)	0.020 (3)
C19	0.051 (3)	0.102 (4)	0.065 (4)	0.011 (3)	0.002 (2)	−0.012 (3)

Geometric parameters (Å, º)

Si1—C11	1.832 (4)	C7—H7	0.95
Si1—C12	1.847 (5)	C8—C9	1.429 (5)
Si1—C13	1.847 (5)	C8—C15	1.443 (5)
Si1—C14	1.850 (5)	C10—C11	1.207 (5)
Si2—C16	1.835 (4)	C12—H12A	0.98
Si2—C19	1.847 (5)	C12—H12B	0.98
Si2—C18	1.853 (5)	C12—H12C	0.98
Si2—C17	1.854 (5)	C13—H13A	0.98
N1—C1	1.313 (5)	C13—H13B	0.98
N1—C9	1.372 (5)	C13—H13C	0.98
C1—C2	1.404 (5)	C14—H14A	0.98
C1—H1	0.95	C14—H14B	0.98
C2—C3	1.362 (5)	C14—H14C	0.98
C2—H2	0.95	C15—C16	1.207 (5)
C3—C4	1.410 (5)	C17—H17A	0.98
C3—H3	0.95	C17—H17B	0.98
C4—C5	1.419 (5)	C17—H17C	0.98
C4—C9	1.432 (5)	C18—H18A	0.98
C5—C6	1.382 (5)	C18—H18B	0.98
C5—C10	1.446 (5)	C18—H18C	0.98
C6—C7	1.401 (5)	C19—H19A	0.98
C6—H6	0.95	C19—H19B	0.98
C7—C8	1.364 (5)	C19—H19C	0.98
C11—Si1—C12	106.6 (2)	C11—C10—C5	174.3 (4)
C11—Si1—C13	108.3 (2)	C10—C11—Si1	172.8 (4)
C12—Si1—C13	110.5 (3)	Si1—C12—H12A	109.5
C11—Si1—C14	109.85 (19)	Si1—C12—H12B	109.5
C12—Si1—C14	107.8 (2)	H12A—C12—H12B	109.5
C13—Si1—C14	113.5 (3)	Si1—C12—H12C	109.5
C16—Si2—C19	106.6 (2)	H12A—C12—H12C	109.5
C16—Si2—C18	109.0 (2)	H12B—C12—H12C	109.5
C19—Si2—C18	111.7 (3)	Si1—C13—H13A	109.5
C16—Si2—C17	108.9 (2)	Si1—C13—H13B	109.5
C19—Si2—C17	111.0 (2)	H13A—C13—H13B	109.5
C18—Si2—C17	109.5 (3)	Si1—C13—H13C	109.5
C1—N1—C9	117.6 (3)	H13A—C13—H13C	109.5
N1—C1—C2	124.7 (4)	H13B—C13—H13C	109.5
N1—C1—H1	117.7	Si1—C14—H14A	109.5
C2—C1—H1	117.7	Si1—C14—H14B	109.5
C3—C2—C1	118.8 (4)	H14A—C14—H14B	109.5
C3—C2—H2	120.6	Si1—C14—H14C	109.5
C1—C2—H2	120.6	H14A—C14—H14C	109.5
C2—C3—C4	119.6 (4)	H14B—C14—H14C	109.5
C2—C3—H3	120.2	C16—C15—C8	176.1 (4)
C4—C3—H3	120.2	C15—C16—Si2	176.8 (4)
C3—C4—C5	123.2 (3)	Si2—C17—H17A	109.5
C3—C4—C9	117.6 (4)	Si2—C17—H17B	109.5
C5—C4—C9	119.2 (3)	H17A—C17—H17B	109.5
C6—C5—C4	120.0 (4)	Si2—C17—H17C	109.5
C6—C5—C10	121.5 (4)	H17A—C17—H17C	109.5
C4—C5—C10	118.4 (3)	H17B—C17—H17C	109.5
C5—C6—C7	120.3 (4)	Si2—C18—H18A	109.5
C5—C6—H6	119.8	Si2—C18—H18B	109.5
C7—C6—H6	119.8	H18A—C18—H18B	109.5
C8—C7—C6	121.7 (4)	Si2—C18—H18C	109.5
C8—C7—H7	119.1	H18A—C18—H18C	109.5
C6—C7—H7	119.1	H18B—C18—H18C	109.5
C7—C8—C9	119.7 (3)	Si2—C19—H19A	109.5
C7—C8—C15	120.2 (4)	Si2—C19—H19B	109.5
C9—C8—C15	120.1 (3)	H19A—C19—H19B	109.5
N1—C9—C8	119.3 (3)	Si2—C19—H19C	109.5
N1—C9—C4	121.8 (3)	H19A—C19—H19C	109.5
C8—C9—C4	119.0 (4)	H19B—C19—H19C	109.5
C9—N1—C1—C2	−1.9 (6)	C6—C7—C8—C9	−0.9 (6)
N1—C1—C2—C3	2.0 (6)	C6—C7—C8—C15	179.5 (4)
C1—C2—C3—C4	−0.6 (6)	C1—N1—C9—C8	−179.8 (4)
C2—C3—C4—C5	−178.6 (4)	C1—N1—C9—C4	0.5 (5)
C2—C3—C4—C9	−0.7 (5)	C7—C8—C9—N1	−178.6 (4)
C3—C4—C5—C6	178.5 (4)	C15—C8—C9—N1	1.0 (5)
C9—C4—C5—C6	0.6 (6)	C7—C8—C9—C4	1.1 (6)
C3—C4—C5—C10	−1.0 (6)	C15—C8—C9—C4	−179.3 (3)
C9—C4—C5—C10	−178.9 (3)	C3—C4—C9—N1	0.7 (5)
C4—C5—C6—C7	−0.4 (6)	C5—C4—C9—N1	178.7 (3)
C10—C5—C6—C7	179.1 (4)	C3—C4—C9—C8	−178.9 (3)
C5—C6—C7—C8	0.5 (7)	C5—C4—C9—C8	−1.0 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···N1^i	0.95	2.69	3.483 (5)	141
C14—H14C···N1^ii	0.98	2.80	3.671 (6)	149

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