(3,5-Dimethyl-1H-pyrazol-1-yl)tri­methyl­silane

The title compound, C₈H₁₆N₂Si, crystallizes in the the ortho­rhom­bic space group P2₁2₁2₁ with one mol­ecule in the asymmetric unit. The Si—N bond is 1.782 (2) Å, which is substanti­ally longer than is found in comparable (3,5-di­methyl­pyrazol­yl)silanes. The tri­methyl­silyl group adopts a staggered conformation with respect to the planar 3,5-di­methyl­pyrazolyl unit. C—H...N hydrogen bonds between neighboring mol­ecules form a strand of mol­ecules along the b-axis direction.

Key indicators

• Single-crystal X-ray study
• T = 250 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.030
• wR factor = 0.080
• Data-to-parameter ratio = 22.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Low    'MainMol' Ueq as Compared to Neighbors of        Si1 Check
PLAT480_ALERT_4_C Long H...A H-Bond Reported H6B      ..N2       .       2.75 Ang.
PLAT911_ALERT_3_C Missing FCF Refl Between Thmin & STh/L=    0.600          7 Report
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          6 Note
PLAT978_ALERT_2_C Number C-C Bonds with Positive Residual Density.          0 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   0 ALERT level G = General information/check it is not something unexpected

   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
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: X-AREA (Stoe, 2009); cell refinement: X-AREA (Stoe, 2009); data reduction: X-RED (Stoe, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL2014/7 (Sheldrick 2015).

(3,5-Dimethyl-1H-pyrazol-1-yl)trimethylsilane

Crystal data

C8H16N2Si	Dx = 1.087 Mg m^−3
Mr = 168.32	Melting point: 260 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
a = 6.1056 (3) Å	Cell parameters from 32385 reflections
b = 10.8114 (7) Å	θ = 2.3–29.7°
c = 15.5867 (9) Å	µ = 0.18 mm^−1
V = 1028.88 (10) Å^3	T = 250 K
Z = 4	Capillary, colourless
F(000) = 368	0.50 × 0.40 × 0.40 mm

Data collection

STOE IPDS 2 diffractometer	2346 independent reflections
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus	2258 reflections with I > 2σ(I)
Plane graphite monochromator	Rint = 0.048
Detector resolution: 6.67 pixels mm^-1	θmax = 27.5°, θmin = 2.3°
rotation method scans	h = −7→6
Absorption correction: integration (X-RED; Stoe, 2009)	k = −14→14
Tmin = 0.708, Tmax = 0.932	l = −19→20
8249 measured reflections

Refinement

Refinement on F^2	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.0384P)^2 + 0.1226P] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.030	(Δ/σ)max < 0.001
wR(F^2) = 0.080	Δρmax = 0.12 e Å^−3
S = 1.09	Δρmin = −0.15 e Å^−3
2346 reflections	Extinction correction: SHELXL-2014/7 (Sheldrick 2015, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
106 parameters	Extinction coefficient: 0.038 (8)
0 restraints	Absolute structure: Flack x determined using 896 quotients [(I^+)-(I^-)]/[(I^+)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.07 (9)
Hydrogen site location: inferred from neighbouring sites

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

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

	x	y	z	Uiso*/Ueq
Si1	1.09038 (8)	0.83129 (5)	0.28856 (3)	0.03560 (16)
N1	0.9829 (3)	0.91025 (15)	0.37963 (9)	0.0371 (3)
N2	0.8044 (3)	0.98582 (17)	0.36345 (11)	0.0449 (4)
C1	1.2467 (4)	0.8620 (3)	0.49915 (16)	0.0604 (6)
H1A	1.2704	0.8905	0.5574	0.091*
H1B	1.3765	0.8782	0.4651	0.091*
H1C	1.2171	0.7738	0.4996	0.091*
C2	1.0558 (3)	0.92883 (18)	0.46120 (11)	0.0390 (4)
C3	0.9227 (4)	1.01575 (19)	0.49782 (12)	0.0443 (4)
H3	0.9317	1.0469	0.5540	0.053*
C4	0.7709 (4)	1.04880 (18)	0.43507 (13)	0.0422 (4)
C5	0.5894 (5)	1.1411 (2)	0.44085 (18)	0.0670 (7)
H5A	0.6504	1.2230	0.4493	0.100*
H5B	0.4951	1.1204	0.4888	0.100*
H5C	0.5049	1.1397	0.3882	0.100*
C6	1.2361 (4)	0.6905 (2)	0.32373 (15)	0.0544 (6)
H6A	1.3721	0.7136	0.3516	0.082*
H6B	1.2677	0.6390	0.2743	0.082*
H6C	1.1450	0.6449	0.3637	0.082*
C7	1.2781 (5)	0.9387 (2)	0.23290 (16)	0.0593 (6)
H7A	1.1987	1.0127	0.2163	0.089*
H7B	1.3368	0.8989	0.1821	0.089*
H7C	1.3972	0.9610	0.2711	0.089*
C8	0.8569 (4)	0.7920 (3)	0.21896 (16)	0.0589 (6)
H8A	0.7518	0.7433	0.2511	0.088*
H8B	0.9084	0.7447	0.1701	0.088*
H8C	0.7875	0.8675	0.1990	0.088*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Si1	0.0353 (2)	0.0376 (3)	0.0339 (2)	0.0038 (2)	0.0023 (2)	0.00083 (19)
N1	0.0377 (8)	0.0398 (8)	0.0338 (7)	0.0062 (7)	0.0010 (6)	0.0016 (6)
N2	0.0477 (10)	0.0474 (9)	0.0395 (8)	0.0141 (8)	−0.0014 (7)	0.0014 (7)
C1	0.0550 (13)	0.0720 (16)	0.0541 (13)	0.0143 (12)	−0.0176 (10)	−0.0073 (11)
C2	0.0396 (10)	0.0414 (9)	0.0361 (8)	−0.0028 (8)	−0.0016 (8)	0.0000 (7)
C3	0.0515 (11)	0.0435 (10)	0.0380 (8)	−0.0020 (10)	0.0016 (9)	−0.0049 (8)
C4	0.0452 (11)	0.0375 (10)	0.0438 (10)	0.0042 (8)	0.0072 (8)	−0.0007 (7)
C5	0.0701 (16)	0.0590 (14)	0.0718 (16)	0.0264 (14)	0.0064 (14)	−0.0074 (11)
C6	0.0651 (14)	0.0476 (12)	0.0506 (12)	0.0175 (11)	0.0024 (11)	0.0007 (9)
C7	0.0599 (14)	0.0557 (13)	0.0623 (14)	−0.0014 (12)	0.0219 (12)	0.0060 (10)
C8	0.0500 (12)	0.0713 (15)	0.0554 (13)	0.0044 (11)	−0.0075 (10)	−0.0176 (12)

Geometric parameters (Å, º)

Si1—N1	1.7816 (15)	C4—C5	1.494 (3)
Si1—C8	1.841 (2)	C5—H5A	0.9700
Si1—C6	1.847 (2)	C5—H5B	0.9700
Si1—C7	1.848 (2)	C5—H5C	0.9700
N1—C2	1.362 (2)	C6—H6A	0.9700
N1—N2	1.385 (2)	C6—H6B	0.9700
N2—C4	1.324 (3)	C6—H6C	0.9700
C1—C2	1.494 (3)	C7—H7A	0.9700
C1—H1A	0.9700	C7—H7B	0.9700
C1—H1B	0.9700	C7—H7C	0.9700
C1—H1C	0.9700	C8—H8A	0.9700
C2—C3	1.367 (3)	C8—H8B	0.9700
C3—C4	1.394 (3)	C8—H8C	0.9700
C3—H3	0.9400
N1—Si1—C8	107.15 (10)	C4—C5—H5A	109.5
N1—Si1—C6	109.63 (9)	C4—C5—H5B	109.5
C8—Si1—C6	110.98 (13)	H5A—C5—H5B	109.5
N1—Si1—C7	107.53 (10)	C4—C5—H5C	109.5
C8—Si1—C7	110.39 (13)	H5A—C5—H5C	109.5
C6—Si1—C7	111.02 (13)	H5B—C5—H5C	109.5
C2—N1—N2	109.87 (15)	Si1—C6—H6A	109.5
C2—N1—Si1	133.98 (14)	Si1—C6—H6B	109.5
N2—N1—Si1	115.29 (11)	H6A—C6—H6B	109.5
C4—N2—N1	105.74 (16)	Si1—C6—H6C	109.5
C2—C1—H1A	109.5	H6A—C6—H6C	109.5
C2—C1—H1B	109.5	H6B—C6—H6C	109.5
H1A—C1—H1B	109.5	Si1—C7—H7A	109.5
C2—C1—H1C	109.5	Si1—C7—H7B	109.5
H1A—C1—H1C	109.5	H7A—C7—H7B	109.5
H1B—C1—H1C	109.5	Si1—C7—H7C	109.5
N1—C2—C3	107.29 (18)	H7A—C7—H7C	109.5
N1—C2—C1	123.58 (18)	H7B—C7—H7C	109.5
C3—C2—C1	129.12 (19)	Si1—C8—H8A	109.5
C2—C3—C4	106.16 (17)	Si1—C8—H8B	109.5
C2—C3—H3	126.9	H8A—C8—H8B	109.5
C4—C3—H3	126.9	Si1—C8—H8C	109.5
N2—C4—C3	110.94 (18)	H8A—C8—H8C	109.5
N2—C4—C5	120.6 (2)	H8B—C8—H8C	109.5
C3—C4—C5	128.5 (2)
C8—Si1—N1—C2	156.8 (2)	Si1—N1—C2—C3	169.00 (16)
C6—Si1—N1—C2	36.3 (2)	N2—N1—C2—C1	−179.88 (19)
C7—Si1—N1—C2	−84.5 (2)	Si1—N1—C2—C1	−11.4 (3)
C8—Si1—N1—N2	−35.13 (18)	N1—C2—C3—C4	−0.7 (2)
C6—Si1—N1—N2	−155.65 (15)	C1—C2—C3—C4	179.8 (2)
C7—Si1—N1—N2	83.55 (17)	N1—N2—C4—C3	−0.3 (2)
C2—N1—N2—C4	−0.1 (2)	N1—N2—C4—C5	179.69 (19)
Si1—N1—N2—C4	−171.00 (14)	C2—C3—C4—N2	0.6 (3)
N2—N1—C2—C3	0.5 (2)	C2—C3—C4—C5	−179.4 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6B···N2^i	0.97	2.75	3.670 (3)	159

Symmetry code: (i) −x+2, y−1/2, −z+1/2.