3,3-Penta­methyl­enediaziridine

The title compound, C₆H₁₂N₂, is the first free N,N-unsubstituted 3,3-di­alkyl­diaziridine to be structurally characterized. The crystal structure indicates the presence of intermolecular N—H...N hydrogen bonds, resulting in a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.034
• wR factor = 0.088
• Data-to-parameter ratio = 9.6

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT374_ALERT_2_A Long   N - N         Bond  N11    -   N12    ...       1.51 Ang.

Alert level C
PLAT088_ALERT_3_C Poor Data / Parameter Ratio ....................       9.64

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   0 ALERT type 4 Improvement, methodology, query or suggestion

---

Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: NRC-2 and NRC-2A (Ahmed et al., 1973); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997) and PLATON (Spek, 1995); software used to prepare material for publication: SHELXL97.

3,3-Pentamethylenediaziridine

Crystal data

C6H12N2	F(000) = 248.0
Mr = 112.18	Dx = 1.120 Mg m^−3
Monoclinic, P21/c	Melting point: 107 K
Hall symbol: -P 2ybc	Cu Kα radiation, λ = 1.54178 Å
a = 10.373 (3) Å	Cell parameters from 25 reflections
b = 8.037 (3) Å	θ = 20.0–25.0°
c = 8.077 (3) Å	µ = 0.54 mm^−1
β = 98.86 (3)°	T = 293 K
V = 665.3 (4) Å^3	Block, colourless
Z = 4	0.40 × 0.36 × 0.23 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	872 reflections with I > 2σ(I)
Radiation source: normal-focus xray tube	Rint = 0.070
Graphite monochromator	θmax = 69.9°, θmin = 4.3°
ω scan	h = −12→12
Absorption correction: integration (ABSORP in NRCVAX; Gabe et al, 1989)	k = −9→9
Tmin = 0.819, Tmax = 0.898	l = −9→9
19833 measured reflections	5 standard reflections every 60 min
1253 independent reflections	intensity decay: 2.1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.034	All H-atom parameters refined
wR(F^2) = 0.088	w = 1/[σ^2(Fo^2) + (0.0551P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.90	(Δ/σ)max = 0.001
1253 reflections	Δρmax = 0.12 e Å^−3
130 parameters	Δρmin = −0.11 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.072 (4)

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.

Refinement. Refinement of F² against ALL reflections. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating R-factor_obs 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	Occ. (<1)
N11	0.53841 (11)	0.94402 (18)	0.68680 (19)	0.0725 (4)
H11A	0.519 (4)	0.836 (6)	0.706 (5)	0.141 (15)*	0.50
H11B	0.521 (4)	0.967 (5)	0.580 (4)	0.114 (14)*	0.50
N12	0.52104 (10)	1.06808 (16)	0.82174 (16)	0.0682 (4)
H12A	0.483 (3)	1.157 (4)	0.756 (4)	0.080 (8)*	0.50
H12B	0.508 (3)	1.015 (4)	0.923 (3)	0.075 (8)*	0.50
C1	0.64843 (11)	1.02759 (14)	0.78250 (13)	0.0541 (3)
C2	0.73685 (13)	0.92490 (19)	0.90762 (17)	0.0681 (4)
H2A	0.6801 (15)	0.8388 (19)	0.9542 (17)	0.092 (4)*
H2B	0.7770 (15)	0.9972 (18)	1.0029 (17)	0.090 (5)*
C3	0.84431 (14)	0.8457 (2)	0.8262 (2)	0.0762 (4)
H3A	0.9075 (15)	0.7837 (19)	0.9161 (19)	0.097 (5)*
H3B	0.8021 (15)	0.7600 (19)	0.741 (2)	0.094 (5)*
C4	0.91702 (13)	0.9740 (2)	0.7386 (2)	0.0822 (5)
H4A	0.9852 (15)	0.9166 (19)	0.6830 (16)	0.093 (5)*
H4B	0.9613 (15)	1.0492 (19)	0.8250 (18)	0.094 (5)*
C5	0.82412 (13)	1.0722 (2)	0.61154 (18)	0.0750 (4)
H5A	0.7833 (14)	0.9945 (17)	0.5185 (16)	0.081 (4)*
H5B	0.8722 (14)	1.1564 (19)	0.5549 (18)	0.096 (5)*
C6	0.71696 (12)	1.15454 (17)	0.69129 (17)	0.0633 (4)
H6A	0.7559 (15)	1.2415 (18)	0.7779 (18)	0.088 (4)*
H6B	0.6488 (13)	1.2098 (15)	0.6059 (17)	0.076 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N11	0.0553 (6)	0.0727 (8)	0.0895 (9)	−0.0084 (6)	0.0117 (6)	−0.0100 (7)
N12	0.0582 (6)	0.0736 (8)	0.0764 (7)	0.0117 (5)	0.0220 (5)	0.0074 (6)
C1	0.0480 (6)	0.0558 (6)	0.0590 (6)	0.0019 (5)	0.0104 (5)	0.0016 (5)
C2	0.0623 (7)	0.0761 (9)	0.0662 (8)	0.0130 (7)	0.0112 (6)	0.0120 (7)
C3	0.0615 (8)	0.0867 (10)	0.0797 (9)	0.0204 (7)	0.0080 (7)	0.0061 (8)
C4	0.0513 (7)	0.1095 (12)	0.0865 (10)	0.0066 (8)	0.0131 (7)	0.0023 (9)
C5	0.0569 (7)	0.0954 (10)	0.0752 (9)	−0.0054 (7)	0.0181 (6)	0.0094 (8)
C6	0.0567 (7)	0.0635 (8)	0.0695 (8)	−0.0065 (6)	0.0090 (6)	0.0059 (7)

Geometric parameters (Å, º)

N11—C1	1.4420 (16)	C3—C4	1.515 (2)
N11—N12	1.5083 (17)	C3—H3A	1.029 (16)
N11—H11A	0.91 (5)	C3—H3B	1.024 (16)
N11—H11B	0.87 (3)	C4—C5	1.517 (2)
N12—C1	1.4427 (14)	C4—H4A	1.006 (15)
N12—H12A	0.94 (3)	C4—H4B	0.983 (15)
N12—H12B	0.95 (2)	C5—C6	1.5195 (18)
C1—C6	1.5002 (16)	C5—H5A	1.018 (13)
C1—C2	1.5027 (17)	C5—H5B	0.993 (16)
C2—C3	1.5186 (18)	C6—H6A	1.027 (15)
C2—H2A	1.017 (15)	C6—H6B	1.011 (13)
C2—H2B	1.002 (14)
C1—N11—N12	58.50 (7)	C4—C3—C2	111.62 (13)
C1—N11—H11A	122 (3)	C4—C3—H3A	110.5 (9)
N12—N11—H11A	117 (2)	C2—C3—H3A	109.1 (8)
C1—N11—H11B	117 (3)	C4—C3—H3B	109.6 (9)
N12—N11—H11B	123 (3)	C2—C3—H3B	107.9 (9)
H11A—N11—H11B	111 (4)	H3A—C3—H3B	108.0 (12)
C1—N12—N11	58.45 (7)	C3—C4—C5	111.09 (12)
C1—N12—H12A	111.6 (17)	C3—C4—H4A	109.3 (8)
N11—N12—H12A	100.5 (18)	C5—C4—H4A	110.7 (8)
C1—N12—H12B	110.4 (17)	C3—C4—H4B	107.4 (9)
N11—N12—H12B	112.2 (17)	C5—C4—H4B	109.8 (9)
H12A—N12—H12B	136 (2)	H4A—C4—H4B	108.3 (13)
N11—C1—N12	63.05 (8)	C4—C5—C6	111.71 (11)
N11—C1—C6	116.70 (11)	C4—C5—H5A	109.2 (8)
N12—C1—C6	118.28 (11)	C6—C5—H5A	109.4 (8)
N11—C1—C2	117.09 (12)	C4—C5—H5B	110.7 (8)
N12—C1—C2	117.45 (10)	C6—C5—H5B	110.6 (8)
C6—C1—C2	114.68 (11)	H5A—C5—H5B	105.0 (11)
C1—C2—C3	110.58 (11)	C1—C6—C5	110.18 (11)
C1—C2—H2A	107.1 (8)	C1—C6—H6A	107.2 (8)
C3—C2—H2A	112.3 (8)	C5—C6—H6A	110.4 (8)
C1—C2—H2B	109.7 (8)	C1—C6—H6B	107.4 (7)
C3—C2—H2B	109.2 (9)	C5—C6—H6B	112.5 (7)
H2A—C2—H2B	107.8 (11)	H6A—C6—H6B	109.0 (10)
N12—N11—C1—C6	−109.83 (13)	C1—C2—C3—C4	53.23 (18)
N12—N11—C1—C2	108.71 (12)	C2—C3—C4—C5	−55.61 (18)
N11—N12—C1—C6	107.39 (13)	C3—C4—C5—C6	56.07 (19)
N11—N12—C1—C2	−108.15 (14)	N11—C1—C6—C5	−88.99 (14)
N11—C1—C2—C3	89.02 (15)	N12—C1—C6—C5	−161.20 (11)
N12—C1—C2—C3	161.08 (12)	C2—C1—C6—C5	53.39 (14)
C6—C1—C2—C3	−53.21 (16)	C4—C5—C6—C1	−53.88 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H11A···N12^i	0.91	2.20	3.082 (2)	164
N11—H11B···N11^ii	0.87	2.26	3.132 (3)	173
N12—H12A···N11^iii	0.94	2.37	3.082 (2)	132
N12—H12B···N12^iv	0.95	2.23	3.173 (3)	171

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