2-[1-(tert-But-oxy-carbonyl)-pyrrolidin-2-yl]-4,4,5,5-tetra-methyl-4,5-dihydro-1H-imidazole-1-oxyl 3-oxide.

In the title compound, C(16)H(28)N(3)O(4), the plane of the pyrrolidine ring system is twisted with respect to the plane of the nitronyl nitroxide unit, making a dihedral angle of 79.80 (6)°. The crystal structure is stabilized by C-H⋯O hydrogen bonds.

Related literature

For the preparation of the title compound, see: Ullman et al. (1974 ▶). For the properties of nitronyl nitroxide radicals, see: Iqbal et al. (2009 ▶); Qin et al. (2009 ▶); Tanaka et al. (2007 ▶); Soule et al. (2007 ▶). For puckering parameters, see: Cremer & Pople (1975).

Experimental

Crystal data

C16H28N3O4

M = 326.41

Monoclinic,

a = 6.1016 (12) Å

b = 10.392 (2) Å

c = 14.488 (3) Å

β = 101.312 (3)°

V = 900.8 (3) Å3

Z = 2

Mo Kα radiation

μ = 0.09 mm−1

T = 296 K

0.36 × 0.28 × 0.17 mm

Data collection

Bruker SMART CCD area-detector diffractometer

4494 measured reflections

1686 independent reflections

1347 reflections with I > 2σ(I)

R int = 0.048

Refinement

R[F 2 > 2σ(F 2)] = 0.042

wR(F 2) = 0.104

S = 0.97

1686 reflections

215 parameters

1 restraint

H-atom parameters constrained

Δρmax = 0.18 e Å−3

Δρmin = −0.20 e Å−3

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ▶) and ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶) and PLATON (Spek,2009 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810020672/dn2566sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810020672/dn2566Isup2.hkl

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

C16H28N3O4	F(000) = 354
Mr = 326.41	Dx = 1.203 Mg m−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1546 reflections
a = 6.1016 (12) Å	θ = 2.4–21.6°
b = 10.392 (2) Å	µ = 0.09 mm−1
c = 14.488 (3) Å	T = 296 K
β = 101.312 (3)°	Block, red
V = 900.8 (3) Å3	0.36 × 0.28 × 0.17 mm
Z = 2

Bruker SMART CCD area-detector diffractometer	1347 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.048
graphite	θmax = 25.1°, θmin = 2.4°
phi and ω scans	h = −7→7
4494 measured reflections	k = −6→12
1686 independent reflections	l = −16→17

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.042	H-atom parameters constrained
wR(F2) = 0.104	w = 1/[σ2(Fo2) + (0.0673P)2] where P = (Fo2 + 2Fc2)/3
S = 0.97	(Δ/σ)max < 0.001
1686 reflections	Δρmax = 0.18 e Å−3
215 parameters	Δρmin = −0.19 e Å−3
1 restraint	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.022 (5)

Experimental. The absolute structure cannot be determined beacuse there are no atoms heaver than silicon in the molecular.

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
N1	0.0929 (4)	0.3494 (3)	0.78508 (14)	0.0442 (6)
N2	0.3330 (4)	0.4804 (2)	0.86782 (15)	0.0434 (6)
N3	0.1712 (4)	0.6757 (2)	0.71424 (15)	0.0471 (6)
O1	0.3991 (4)	0.7310 (3)	0.61493 (15)	0.0669 (7)
O2	−0.0793 (3)	0.3080 (2)	0.72759 (14)	0.0615 (6)
O3	0.4286 (4)	0.5857 (2)	0.90224 (15)	0.0621 (6)
O4	0.2361 (4)	0.5320 (2)	0.61039 (13)	0.0575 (6)
C1	0.2011 (6)	0.3558 (4)	0.5093 (2)	0.0656 (9)
H1A	0.2562	0.3044	0.5640	0.098*
H1B	0.2408	0.3160	0.4550	0.098*
H1C	0.0414	0.3625	0.5004	0.098*
C2	0.5524 (6)	0.4831 (4)	0.5354 (3)	0.0718 (10)
H2A	0.6115	0.5689	0.5434	0.108*
H2B	0.5934	0.4448	0.4809	0.108*
H2C	0.6123	0.4327	0.5900	0.108*
C3	0.1978 (7)	0.5764 (4)	0.4421 (2)	0.0799 (12)
H3A	0.0387	0.5782	0.4375	0.120*
H3B	0.2316	0.5450	0.3842	0.120*
H3C	0.2569	0.6617	0.4541	0.120*
C4	0.3028 (5)	0.4878 (3)	0.52248 (18)	0.0488 (8)
C5	0.2803 (5)	0.6526 (3)	0.64280 (19)	0.0482 (7)
C6	0.1631 (6)	0.8032 (3)	0.7549 (2)	0.0556 (8)
H6A	0.1705	0.8699	0.7088	0.067*
H6B	0.2842	0.8153	0.8086	0.067*
C7	−0.0620 (7)	0.8035 (3)	0.7848 (3)	0.0690 (10)
H9A	−0.0623	0.8630	0.8364	0.083*
H9B	−0.1810	0.8269	0.7327	0.083*
C8	−0.0877 (6)	0.6663 (3)	0.8153 (2)	0.0576 (9)
H10A	−0.2443	0.6437	0.8084	0.069*
H10B	−0.0150	0.6542	0.8806	0.069*
C9	0.0256 (4)	0.5839 (3)	0.74985 (18)	0.0417 (7)
H11	−0.0878	0.5518	0.6974	0.050*
C10	0.1523 (4)	0.4731 (3)	0.79995 (17)	0.0385 (6)
C11	0.2665 (5)	0.2596 (3)	0.8383 (2)	0.0506 (8)
C12	0.4042 (6)	0.2131 (4)	0.7676 (2)	0.0705 (11)
H15A	0.3088	0.1683	0.7172	0.106*
H15B	0.5194	0.1560	0.7983	0.106*
H15C	0.4709	0.2856	0.7427	0.106*
C13	0.1549 (6)	0.1467 (4)	0.8763 (3)	0.0692 (10)
H16A	0.0599	0.1775	0.9170	0.104*
H16B	0.2669	0.0909	0.9110	0.104*
H16C	0.0670	0.0999	0.8249	0.104*
C14	0.3947 (4)	0.3532 (3)	0.91403 (18)	0.0450 (7)
C15	0.6454 (5)	0.3379 (4)	0.9356 (2)	0.0635 (9)
H18A	0.7020	0.3464	0.8786	0.095*
H18B	0.6833	0.2544	0.9625	0.095*
H18C	0.7105	0.4031	0.9795	0.095*
C16	0.3053 (5)	0.3565 (4)	1.00551 (19)	0.0596 (9)
H17A	0.1457	0.3658	0.9911	0.089*
H17B	0.3702	0.4279	1.0432	0.089*
H17C	0.3439	0.2778	1.0396	0.089*

	U11	U22	U33	U12	U13	U23
N1	0.0490 (13)	0.0398 (15)	0.0440 (12)	−0.0025 (12)	0.0091 (10)	0.0019 (11)
N2	0.0451 (13)	0.0403 (15)	0.0455 (12)	−0.0073 (13)	0.0104 (10)	0.0000 (12)
N3	0.0717 (15)	0.0350 (13)	0.0405 (11)	−0.0039 (13)	0.0252 (11)	−0.0009 (11)
O1	0.0936 (17)	0.0510 (14)	0.0679 (13)	−0.0193 (14)	0.0449 (12)	−0.0023 (12)
O2	0.0602 (12)	0.0519 (15)	0.0653 (12)	−0.0125 (11)	−0.0050 (10)	−0.0020 (11)
O3	0.0670 (13)	0.0529 (15)	0.0627 (12)	−0.0176 (13)	0.0034 (10)	−0.0058 (12)
O4	0.0907 (15)	0.0449 (13)	0.0470 (11)	−0.0064 (13)	0.0380 (10)	−0.0074 (10)
C1	0.087 (2)	0.058 (2)	0.0559 (17)	−0.002 (2)	0.0249 (15)	−0.0131 (17)
C2	0.072 (2)	0.069 (3)	0.078 (2)	0.002 (2)	0.0212 (16)	−0.020 (2)
C3	0.113 (3)	0.077 (3)	0.0487 (17)	0.017 (2)	0.0119 (17)	0.0065 (19)
C4	0.0631 (17)	0.052 (2)	0.0350 (13)	0.0042 (16)	0.0191 (11)	−0.0044 (14)
C5	0.0683 (19)	0.0390 (18)	0.0405 (13)	−0.0040 (16)	0.0183 (13)	−0.0013 (14)
C6	0.085 (2)	0.0382 (17)	0.0477 (15)	−0.0046 (18)	0.0227 (15)	−0.0050 (14)
C7	0.102 (3)	0.048 (2)	0.0658 (19)	0.009 (2)	0.0381 (18)	0.0000 (17)
C8	0.072 (2)	0.051 (2)	0.0579 (17)	0.0066 (18)	0.0331 (15)	0.0045 (16)
C9	0.0506 (15)	0.0379 (16)	0.0382 (12)	−0.0024 (14)	0.0123 (11)	0.0002 (13)
C10	0.0457 (14)	0.0363 (16)	0.0358 (12)	−0.0047 (14)	0.0141 (11)	0.0014 (13)
C11	0.0507 (17)	0.043 (2)	0.0583 (17)	0.0013 (15)	0.0113 (13)	0.0030 (14)
C12	0.073 (2)	0.069 (3)	0.072 (2)	0.013 (2)	0.0214 (17)	−0.014 (2)
C13	0.077 (2)	0.045 (2)	0.084 (2)	−0.0033 (19)	0.0152 (18)	0.0179 (19)
C14	0.0482 (15)	0.0446 (18)	0.0428 (14)	0.0008 (15)	0.0104 (11)	0.0058 (14)
C15	0.0514 (16)	0.071 (3)	0.0672 (18)	0.0057 (18)	0.0081 (14)	0.0002 (19)
C16	0.0642 (17)	0.071 (2)	0.0466 (15)	0.0057 (19)	0.0187 (13)	0.0097 (17)

N1—O2	1.281 (3)	C6—H6B	0.9700
N1—C10	1.341 (4)	C7—C8	1.511 (5)
N1—C11	1.506 (4)	C7—H9A	0.9700
N2—O3	1.293 (3)	C7—H9B	0.9700
N2—C10	1.328 (3)	C8—C9	1.538 (4)
N2—C14	1.495 (4)	C8—H10A	0.9700
N3—C5	1.357 (4)	C8—H10B	0.9700
N3—C6	1.455 (4)	C9—C10	1.494 (4)
N3—C9	1.464 (4)	C9—H11	0.9800
O1—C5	1.211 (4)	C11—C13	1.513 (5)
O4—C5	1.347 (4)	C11—C12	1.526 (4)
O4—C4	1.484 (3)	C11—C14	1.557 (4)
C1—C4	1.502 (5)	C12—H15A	0.9600
C1—H1A	0.9600	C12—H15B	0.9600
C1—H1B	0.9600	C12—H15C	0.9600
C1—H1C	0.9600	C13—H16A	0.9600
C2—C4	1.499 (5)	C13—H16B	0.9600
C2—H2A	0.9600	C13—H16C	0.9600
C2—H2B	0.9600	C14—C15	1.509 (4)
C2—H2C	0.9600	C14—C16	1.529 (4)
C3—C4	1.523 (4)	C15—H18A	0.9600
C3—H3A	0.9600	C15—H18B	0.9600
C3—H3B	0.9600	C15—H18C	0.9600
C3—H3C	0.9600	C16—H17A	0.9600
C6—C7	1.518 (5)	C16—H17B	0.9600
C6—H6A	0.9700	C16—H17C	0.9600
O2—N1—C10	126.0 (2)	C7—C8—H10A	110.7
O2—N1—C11	122.0 (3)	C9—C8—H10A	110.7
C10—N1—C11	111.8 (2)	C7—C8—H10B	110.7
O3—N2—C10	125.4 (2)	C9—C8—H10B	110.7
O3—N2—C14	121.35 (19)	H10A—C8—H10B	108.8
C10—N2—C14	112.4 (2)	N3—C9—C10	112.4 (2)
C5—N3—C6	122.0 (3)	N3—C9—C8	103.4 (2)
C5—N3—C9	125.2 (2)	C10—C9—C8	112.4 (2)
C6—N3—C9	112.3 (2)	N3—C9—H11	109.5
C5—O4—C4	121.2 (2)	C10—C9—H11	109.5
C4—C1—H1A	109.5	C8—C9—H11	109.5
C4—C1—H1B	109.5	N2—C10—N1	109.4 (2)
H1A—C1—H1B	109.5	N2—C10—C9	126.2 (3)
C4—C1—H1C	109.5	N1—C10—C9	124.3 (2)
H1A—C1—H1C	109.5	N1—C11—C13	110.2 (2)
H1B—C1—H1C	109.5	N1—C11—C12	106.1 (2)
C4—C2—H2A	109.5	C13—C11—C12	110.2 (3)
C4—C2—H2B	109.5	N1—C11—C14	100.3 (2)
H2A—C2—H2B	109.5	C13—C11—C14	115.4 (3)
C4—C2—H2C	109.5	C12—C11—C14	113.9 (2)
H2A—C2—H2C	109.5	C11—C12—H15A	109.5
H2B—C2—H2C	109.5	C11—C12—H15B	109.5
C4—C3—H3A	109.5	H15A—C12—H15B	109.5
C4—C3—H3B	109.5	C11—C12—H15C	109.5
H3A—C3—H3B	109.5	H15A—C12—H15C	109.5
C4—C3—H3C	109.5	H15B—C12—H15C	109.5
H3A—C3—H3C	109.5	C11—C13—H16A	109.5
H3B—C3—H3C	109.5	C11—C13—H16B	109.5
O4—C4—C2	110.3 (2)	H16A—C13—H16B	109.5
O4—C4—C1	102.5 (2)	C11—C13—H16C	109.5
C2—C4—C1	111.7 (3)	H16A—C13—H16C	109.5
O4—C4—C3	108.9 (3)	H16B—C13—H16C	109.5
C2—C4—C3	112.3 (3)	N2—C14—C15	110.0 (3)
C1—C4—C3	110.7 (3)	N2—C14—C16	105.5 (3)
O1—C5—O4	127.0 (3)	C15—C14—C16	110.0 (2)
O1—C5—N3	123.4 (3)	N2—C14—C11	100.9 (2)
O4—C5—N3	109.6 (3)	C15—C14—C11	115.4 (3)
N3—C6—C7	102.8 (3)	C16—C14—C11	114.1 (2)
N3—C6—H6A	111.2	C14—C15—H18A	109.5
C7—C6—H6A	111.2	C14—C15—H18B	109.5
N3—C6—H6B	111.2	H18A—C15—H18B	109.5
C7—C6—H6B	111.2	C14—C15—H18C	109.5
H6A—C6—H6B	109.1	H18A—C15—H18C	109.5
C8—C7—C6	103.5 (3)	H18B—C15—H18C	109.5
C8—C7—H9A	111.1	C14—C16—H17A	109.5
C6—C7—H9A	111.1	C14—C16—H17B	109.5
C8—C7—H9B	111.1	H17A—C16—H17B	109.5
C6—C7—H9B	111.1	C14—C16—H17C	109.5
H9A—C7—H9B	109.0	H17A—C16—H17C	109.5
C7—C8—C9	105.0 (2)	H17B—C16—H17C	109.5
C5—O4—C4—C2	66.4 (4)	C11—N1—C10—C9	173.9 (2)
C5—O4—C4—C1	−174.5 (3)	N3—C9—C10—N2	50.4 (3)
C5—O4—C4—C3	−57.3 (4)	C8—C9—C10—N2	−65.8 (4)
C4—O4—C5—O1	−10.5 (5)	N3—C9—C10—N1	−132.5 (3)
C4—O4—C5—N3	169.9 (2)	C8—C9—C10—N1	111.3 (3)
C6—N3—C5—O1	8.7 (5)	O2—N1—C11—C13	−43.4 (4)
C9—N3—C5—O1	179.8 (3)	C10—N1—C11—C13	141.6 (3)
C6—N3—C5—O4	−171.7 (3)	O2—N1—C11—C12	75.8 (3)
C9—N3—C5—O4	−0.7 (4)	C10—N1—C11—C12	−99.2 (3)
C5—N3—C6—C7	148.7 (3)	O2—N1—C11—C14	−165.5 (2)
C9—N3—C6—C7	−23.4 (3)	C10—N1—C11—C14	19.5 (3)
N3—C6—C7—C8	34.8 (3)	O3—N2—C14—C15	−48.6 (3)
C6—C7—C8—C9	−34.1 (3)	C10—N2—C14—C15	141.3 (2)
C5—N3—C9—C10	69.1 (3)	O3—N2—C14—C16	70.0 (3)
C6—N3—C9—C10	−119.1 (3)	C10—N2—C14—C16	−100.1 (3)
C5—N3—C9—C8	−169.4 (3)	O3—N2—C14—C11	−171.0 (2)
C6—N3—C9—C8	2.4 (3)	C10—N2—C14—C11	19.0 (3)
C7—C8—C9—N3	19.9 (3)	N1—C11—C14—N2	−21.2 (2)
C7—C8—C9—C10	141.4 (3)	C13—C11—C14—N2	−139.5 (3)
O3—N2—C10—N1	−177.0 (2)	C12—C11—C14—N2	91.6 (3)
C14—N2—C10—N1	−7.4 (3)	N1—C11—C14—C15	−139.7 (3)
O3—N2—C10—C9	0.5 (4)	C13—C11—C14—C15	102.0 (3)
C14—N2—C10—C9	170.0 (2)	C12—C11—C14—C15	−26.8 (4)
O2—N1—C10—N2	176.7 (2)	N1—C11—C14—C16	91.4 (3)
C11—N1—C10—N2	−8.6 (3)	C13—C11—C14—C16	−26.9 (4)
O2—N1—C10—C9	−0.8 (4)	C12—C11—C14—C16	−155.7 (3)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···O1	0.96	2.47	3.043 (5)	118
C3—H3C···O1	0.96	2.43	3.025 (4)	120
C9—H11···O2	0.98	2.57	2.942 (4)	102
C16—H17C···O3i	0.96	2.48	3.390 (4)	157

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯O1	0.96	2.47	3.043 (5)	118
C3—H3C⋯O1	0.96	2.43	3.025 (4)	120
C16—H17C⋯O3i	0.96	2.48	3.390 (4)	157

Symmetry code: (i) .