4-Amino-2,2,6,6-tetra­methyl­piperidin-1-ium chloride monohydrate

In the title compound, C₉H₂₁N₂⁺·Cl⁻·H₂O, the piperidine ring adopts a chair conformation. In the crystal structure, the components are linked by N—H...N, O—H...Cl, N—H...Cl and N—H...O hydrogen bonds. There are two independent chloride ions, both on crystallographic twofold rotation axes.

Key indicators

• Single-crystal X-ray study
• T = 113 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.036
• wR factor = 0.085
• Data-to-parameter ratio = 18.5

checkCIF/PLATON results

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PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H2D    ...          ?

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S1. Comment

Hindered amine light stabilizers are one of the most intensively studied classes of stabilizers due to their high photo-stabilization efficiency (Bojinov & Grabchev, 2001). 2,2,6,6-Tetramethylpiperidine-4-amine is an important intermediate of hindered amine light stabilizers.

We report here the crystal structure of the title compound, (I), (Fig. 1), in which the piperidinyl ring adopts a chair conformation. In the crystal, the components are linked by intermolecular N—H···N, O—H···Cl, N—H···Cl and N—H···O hydrogen bonds (Table 1).

Related literature

For related literature, see: Bojinov & Grabchev (2001).

S2. Experimental

The title compound was prepared by dissolving 4-ammonio-2,2,6,6-tetramethylpiperidine in aqueous hydrochloric acid solution. Colourless prisms of (I) were obtained by slow evaporation.

S3. Refinement

The O– and N-bound H atoms were located in a difference map and their positions and U_iso values were freely refined. The C-bound atoms were positioned geometrically (C—H = 0.98–0.99 Å), and refined as riding with U_iso(H)=1.2U_eq(C) or 1.5_eq(methyl C).

Computing details

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); 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: CrystalStructure (Rigaku/MSC, 2005).

Figures

Fig. 1. A view of the molecular structure of (I). Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as spheres of arbitrary radius. The hydrogen bonds are indicated by dashed lines.

4-Amino-2,2,6,6-tetramethylpiperidin-1-ium chloride monohydrate

Crystal data

C9H21N2^+·Cl^−·H2O	Dx = 1.237 Mg m^−3
Mr = 210.74	Melting point > 523 K
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: -P 2n 2ab	Cell parameters from 6541 reflections
a = 14.1959 (9) Å	θ = 1.4–27.9°
b = 12.7099 (7) Å	µ = 0.31 mm^−1
c = 12.5451 (6) Å	T = 113 K
V = 2263.5 (2) Å^3	Prism, colorless
Z = 8	0.32 × 0.26 × 0.20 mm
F(000) = 928

Data collection

Rigaku Saturn diffractometer	2699 independent reflections
Radiation source: rotating anode	2672 reflections with I > 2σ(I)
Confocal monochromator	Rint = 0.030
Detector resolution: 14.63 pixels mm^-1	θmax = 27.9°, θmin = 2.2°
ω scans	h = −18→17
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −16→16
Tmin = 0.898, Tmax = 0.941	l = −16→16
26456 measured reflections

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)] = 0.036	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.085	w = 1/[σ^2(Fo^2) + (0.0337P)^2 + 1.133P] where P = (Fo^2 + 2Fc^2)/3
S = 1.15	(Δ/σ)max = 0.001
2699 reflections	Δρmax = 0.34 e Å^−3
146 parameters	Δρmin = −0.17 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0104 (8)

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. 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.

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

	x	y	z	Uiso*/Ueq
Cl1	0.0000	0.64751 (3)	0.2500	0.02249 (13)
Cl2	0.5000	0.56016 (3)	0.2500	0.01639 (12)
N1	0.25307 (7)	0.33787 (8)	0.40843 (8)	0.0111 (2)
H1A	0.2197 (11)	0.2761 (14)	0.4188 (13)	0.026 (4)*
H1B	0.2920 (11)	0.3283 (12)	0.3533 (13)	0.020 (4)*
N2	0.35317 (8)	0.65104 (8)	0.44971 (9)	0.0143 (2)
H2C	0.3942 (12)	0.6415 (12)	0.3978 (14)	0.020 (4)*
H2D	0.3836 (12)	0.6657 (13)	0.5061 (14)	0.025 (4)*
O1	0.37732 (7)	0.34651 (8)	0.21798 (8)	0.0200 (2)
H1C	0.4126 (13)	0.2927 (15)	0.2264 (14)	0.030*
H1D	0.4113 (13)	0.3976 (15)	0.2268 (14)	0.030*
C1	0.31784 (8)	0.35426 (9)	0.50387 (9)	0.0118 (2)
C2	0.36764 (8)	0.45990 (9)	0.48955 (9)	0.0125 (2)
H2A	0.4132	0.4538	0.4301	0.015*
H2B	0.4038	0.4758	0.5551	0.015*
C3	0.30101 (8)	0.55161 (9)	0.46649 (9)	0.0121 (2)
H3	0.2575	0.5606	0.5286	0.015*
C4	0.24252 (8)	0.52763 (9)	0.36733 (9)	0.0126 (2)
H4A	0.2852	0.5226	0.3051	0.015*
H4B	0.1988	0.5869	0.3544	0.015*
C5	0.18539 (8)	0.42568 (9)	0.37562 (9)	0.0124 (2)
C6	0.38975 (9)	0.26463 (9)	0.50102 (10)	0.0157 (3)
H6A	0.3573	0.1973	0.5111	0.024*
H6B	0.4359	0.2746	0.5582	0.024*
H6C	0.4221	0.2646	0.4320	0.024*
C7	0.26345 (9)	0.34794 (9)	0.60886 (9)	0.0154 (3)
H7A	0.2233	0.4102	0.6163	0.023*
H7B	0.3080	0.3450	0.6685	0.023*
H7C	0.2242	0.2845	0.6091	0.023*
C8	0.14726 (9)	0.39370 (10)	0.26623 (10)	0.0165 (3)
H8A	0.1999	0.3833	0.2168	0.025*
H8B	0.1059	0.4493	0.2390	0.025*
H8C	0.1115	0.3281	0.2728	0.025*
C9	0.10232 (9)	0.43610 (10)	0.45239 (10)	0.0166 (3)
H9A	0.0752	0.3664	0.4659	0.025*
H9B	0.0543	0.4819	0.4208	0.025*
H9C	0.1242	0.4666	0.5197	0.025*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0233 (2)	0.0148 (2)	0.0293 (3)	0.000	−0.00737 (18)	0.000
Cl2	0.0156 (2)	0.0194 (2)	0.0141 (2)	0.000	0.00074 (14)	0.000
N1	0.0117 (5)	0.0105 (5)	0.0110 (4)	0.0000 (4)	0.0002 (4)	−0.0006 (3)
N2	0.0153 (5)	0.0109 (5)	0.0166 (5)	−0.0014 (4)	−0.0005 (4)	0.0000 (4)
O1	0.0166 (5)	0.0188 (5)	0.0246 (5)	0.0000 (4)	−0.0012 (4)	−0.0020 (4)
C1	0.0135 (5)	0.0113 (5)	0.0106 (5)	0.0005 (4)	−0.0014 (4)	0.0003 (4)
C2	0.0129 (5)	0.0114 (5)	0.0131 (5)	−0.0007 (4)	−0.0005 (4)	0.0001 (4)
C3	0.0136 (5)	0.0104 (5)	0.0124 (5)	−0.0004 (4)	0.0007 (4)	−0.0001 (4)
C4	0.0141 (5)	0.0111 (5)	0.0128 (5)	0.0006 (4)	−0.0004 (4)	0.0014 (4)
C5	0.0116 (5)	0.0115 (5)	0.0140 (5)	0.0026 (4)	−0.0008 (4)	0.0007 (4)
C6	0.0165 (6)	0.0130 (6)	0.0176 (6)	0.0013 (4)	−0.0020 (4)	0.0009 (4)
C7	0.0188 (6)	0.0158 (6)	0.0115 (5)	−0.0008 (5)	0.0006 (5)	0.0015 (4)
C8	0.0171 (6)	0.0157 (6)	0.0167 (6)	0.0013 (5)	−0.0038 (5)	−0.0015 (5)
C9	0.0130 (5)	0.0167 (6)	0.0200 (6)	0.0009 (4)	0.0022 (5)	−0.0001 (5)

Geometric parameters (Å, º)

N1—C1	1.5240 (14)	C4—C5	1.5322 (16)
N1—C5	1.5290 (14)	C4—H4A	0.9900
N1—H1A	0.926 (18)	C4—H4B	0.9900
N1—H1B	0.894 (17)	C5—C9	1.5283 (16)
N2—C3	1.4798 (15)	C5—C8	1.5302 (16)
N2—H2C	0.882 (18)	C6—H6A	0.9800
N2—H2D	0.850 (18)	C6—H6B	0.9800
O1—H1C	0.854 (19)	C6—H6C	0.9800
O1—H1D	0.817 (19)	C7—H7A	0.9800
C1—C2	1.5281 (15)	C7—H7B	0.9800
C1—C7	1.5287 (16)	C7—H7C	0.9800
C1—C6	1.5301 (16)	C8—H8A	0.9800
C2—C3	1.5288 (16)	C8—H8B	0.9800
C2—H2A	0.9900	C8—H8C	0.9800
C2—H2B	0.9900	C9—H9A	0.9800
C3—C4	1.5264 (16)	C9—H9B	0.9800
C3—H3	1.0000	C9—H9C	0.9800
C1—N1—C5	119.39 (9)	C5—C4—H4B	108.8
C1—N1—H1A	108.3 (10)	H4A—C4—H4B	107.7
C5—N1—H1A	109.6 (10)	C9—C5—N1	112.24 (9)
C1—N1—H1B	104.7 (10)	C9—C5—C8	108.37 (10)
C5—N1—H1B	106.2 (10)	N1—C5—C8	105.65 (9)
H1A—N1—H1B	108.1 (14)	C9—C5—C4	112.21 (10)
C3—N2—H2C	108.6 (10)	N1—C5—C4	107.64 (9)
C3—N2—H2D	108.9 (12)	C8—C5—C4	110.55 (9)
H2C—N2—H2D	108.0 (15)	C1—C6—H6A	109.5
H1C—O1—H1D	105.9 (18)	C1—C6—H6B	109.5
N1—C1—C2	107.87 (9)	H6A—C6—H6B	109.5
N1—C1—C7	111.41 (9)	C1—C6—H6C	109.5
C2—C1—C7	112.41 (9)	H6A—C6—H6C	109.5
N1—C1—C6	106.40 (9)	H6B—C6—H6C	109.5
C2—C1—C6	110.04 (10)	C1—C7—H7A	109.5
C7—C1—C6	108.54 (9)	C1—C7—H7B	109.5
C1—C2—C3	113.95 (9)	H7A—C7—H7B	109.5
C1—C2—H2A	108.8	C1—C7—H7C	109.5
C3—C2—H2A	108.8	H7A—C7—H7C	109.5
C1—C2—H2B	108.8	H7B—C7—H7C	109.5
C3—C2—H2B	108.8	C5—C8—H8A	109.5
H2A—C2—H2B	107.7	C5—C8—H8B	109.5
N2—C3—C4	109.07 (9)	H8A—C8—H8B	109.5
N2—C3—C2	111.62 (9)	C5—C8—H8C	109.5
C4—C3—C2	109.78 (9)	H8A—C8—H8C	109.5
N2—C3—H3	108.8	H8B—C8—H8C	109.5
C4—C3—H3	108.8	C5—C9—H9A	109.5
C2—C3—H3	108.8	C5—C9—H9B	109.5
C3—C4—C5	113.67 (9)	H9A—C9—H9B	109.5
C3—C4—H4A	108.8	C5—C9—H9C	109.5
C5—C4—H4A	108.8	H9A—C9—H9C	109.5
C3—C4—H4B	108.8	H9B—C9—H9C	109.5
C5—N1—C1—C2	−50.01 (13)	N2—C3—C4—C5	179.86 (9)
C5—N1—C1—C7	73.82 (12)	C2—C3—C4—C5	57.27 (13)
C5—N1—C1—C6	−168.06 (9)	C1—N1—C5—C9	−73.64 (13)
N1—C1—C2—C3	51.43 (12)	C1—N1—C5—C8	168.44 (10)
C7—C1—C2—C3	−71.78 (13)	C1—N1—C5—C4	50.30 (13)
C6—C1—C2—C3	167.12 (9)	C3—C4—C5—C9	71.93 (12)
C1—C2—C3—N2	−178.05 (9)	C3—C4—C5—N1	−52.03 (12)
C1—C2—C3—C4	−56.98 (13)	C3—C4—C5—C8	−166.96 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1D···Cl2	0.817 (19)	2.44 (2)	3.2509 (11)	174.7 (17)
O1—H1C···Cl1^i	0.854 (19)	2.244 (19)	3.0971 (11)	177.7 (17)
N2—H2C···Cl2	0.882 (18)	2.601 (18)	3.4577 (11)	164.2 (13)
N1—H1B···O1	0.894 (17)	2.098 (17)	2.9718 (14)	165.6 (14)
N1—H1A···N2^i	0.926 (18)	1.935 (18)	2.8602 (14)	176.1 (15)

Symmetry code: (i) −x+1/2, y−1/2, z.