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ISSN: 2056-9890

8-Iodo­quinolinium chloride dihydrate

aDepartment of Chemistry, University of South Dakota, 414 E. Clark Street, Vermillion, SD 57069, USA
*Correspondence e-mail: jhoefelm@usd.edu

(Received 4 August 2008; accepted 29 September 2008; online 4 October 2008)

The title compound, C9H7IN+·Cl·2H2O, was obtained during the synthesis of 8-iodo­quinoline from 8-amino­quinoline using the Sandmeyer reaction. The 8-iodo­quinolinium ion is almost planar. Solvent water mol­ecules and chloride ions form a hydrogen-bonded chain along the c axis via O—H⋯Cl links. The 8-iodo­quinolinium ions, which are packed along the c axis with cationic aromatic ππ stacking (centroid–centroid distance = 3.624 Å), are linked to the chain via N—H⋯O hydrogen bonds.

Related literature

For the synthesis, see: Lucas & Kennedy (1943[Lucas, H. J. & Kennedy, E. R. (1943). Org. Synth. Coll. Vol. II, pp. 351-352.]); Sandmeyer (1884[Sandmeyer, T. (1884). Ber. Dtsch. Chem. Ges. 17, 1633-1635.]). For a related structure, see: Son & Hoefelmeyer (2008[Son, J.-H. & Hoefelmeyer, J. D. (2008). Acta Cryst. E64, o2077.]). For related literature, see: Janiak (2000[Janiak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885-3896.]).

[Scheme 1]

Experimental

Crystal data
  • C9H7IN+·Cl·2H2O

  • Mr = 327.54

  • Monoclinic, P 21 /c

  • a = 8.9600 (18) Å

  • b = 17.580 (4) Å

  • c = 7.1700 (14) Å

  • β = 97.13 (3)°

  • V = 1120.7 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 3.07 mm−1

  • T = 100 (2) K

  • 0.71 × 0.67 × 0.54 mm

Data collection
  • Bruker SMART APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.219, Tmax = 0.288 (expected range = 0.145–0.190)

  • 10655 measured reflections

  • 2045 independent reflections

  • 2040 reflections with I > 2σ(I)

  • Rint = 0.020

Refinement
  • R[F2 > 2σ(F2)] = 0.019

  • wR(F2) = 0.046

  • S = 1.25

  • 2045 reflections

  • 143 parameters

  • 6 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.79 e Å−3

  • Δρmin = −0.65 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1 0.82 (4) 2.03 (4) 2.755 (3) 147 (3)
N1—H1⋯I1 0.82 (4) 2.85 (4) 3.320 (2) 119 (3)
O1—H1A⋯O2 0.84 (1) 1.975 (12) 2.807 (3) 173 (5)
O1—H1B⋯Cl1i 0.83 (1) 2.75 (3) 3.382 (3) 134 (4)
O2—H2A⋯Cl1 0.84 (1) 2.435 (16) 3.237 (2) 160 (3)
O2—H2B⋯Cl1ii 0.84 (1) 2.379 (12) 3.211 (2) 170 (3)
Symmetry codes: (i) x, y, z-1; (ii) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

8-Iodoquinoline is a starting material for the synthesis of 8-substituted quinoline derivatives. In this work, 8-iodoquinoline was synthesized starting from 8-aminoquinoline using the Sandmeyer reaction (Sandmeyer, 1884), following the synthesis of iodobenzene (Lucas & Kennedy, 1943). During its synthesis, two 8-iodoquinolinium salt crystals, 8-iodoquinolinium chloride dihydrate and 8-iodoquinolinium triiodide.THF (Son & Hoefelmeyer, 2008) were isolated. The synthesis, characterization and crystal structure of 8-iodoquinolinium chloride dihydrate (Fig. 1) are reported here.

The 8-iodoquinolinium ion is planar, with a maximum deviation of 0.069 (1) Å for the I1 atom. The C8—I1 bond length is 2.110 (3) Å and C9—C8—I1 angle is 121.09 (19) °. A short contact of 3.2083 (10) Å is observed between I1 and Cl1 ion at (1-x, 1-y, 1-z) that is likely due to ion-dipole interaction. The C8—I1···Cl1 angle is almost linear (177.13 (8)°).

Lattice water molecules and chloride ions form an extended hydrogen bonding chain network along the c axis (Table 1). Hydrogen bonding four-membered rings comprising O2 and Cl1 are alternately sharing edges with six-membered rings (in chair form) comprising O2, C1l and O1 along the c axis (Fig. 2). Atom O1 of the six-membered ring is hydrogen-bonded to atom N1 of the quinolinium ion. The 8-iodoquinolinium ions are parallel to each other and form a π-stack that is propogated along the c axis. The π-π stacking distance between the 8-iodoquinolinium rings is 3.624 Å (centroid-centroid distance between the 8-iodoquinolinium rings); there may be weak cationic repulsion between the rings (Janiak, 2000).

Related literature top

For the synthesis, see: Lucas & Kennedy (1943); Sandmeyer (1884). For a related structure, see: Son & Hoefelmeyer (2008). For related literature, see: Janiak (2000); AUTHOR: if you wish to provide higher resolution figures please email new version(s) with your proof comments; Figure 1 in particular could be improved.

Experimental top

A mixture of 8-aminoquinoline (10 g, 0.069 mol) and water (50 ml) was heated with stirring. The mixture was cooled in an ice bath and concentrated HCl (50 ml) was added to form a red solution. An ice-cooled NaNO2 (7.8 g, 0.113 mol) solution in water (50 ml) was slowly transferred to the 8-aminoquinoline solution. A light brown precipitate was formed during the addition step but eventually it disappeared to form a reddish transparent solution. KI (17.9 g, 0.108 mol) dissolved in water (25 ml) was then added to the reaction mixture. Bubbles and brownish vapour evolved during the addition. The solution turned to dark brown with a black precipitate. The solution was then refluxed with a watch glass on top of the beaker, and it turned reddish brown with formation of a heavy organic layer; the black precipitate remained. After cooling and standing overnight, golden brown crystals of 8-iodoquinolinium chloride dihydrate had formed spontaneously in the solution. The mixture was neutralized upon addition of NaOH solution, which led to dissolution of the golden brown crystals and retention of the black precipitate. The liquid portion was separated from the black precipitate. 8-iodoquinoline was recoverd from the liquid portion upon extraction with toluene. Yield: 10.71 g of 8-iodoquinoline (61%). Physical data for 8-iodoquinolinium chloride dihydrate: m.p. 388-390 K (431-433 K after dehydration). 1H NMR (methanol-d4): 7.638–7.716 (dd, 1H, quin CH), 8.144–8.214 (dd, 1H, quin CH), 8.313–8.360 (dd, 1H, quin CH), 8.605–8.647 (dd, 1H, quin CH), 9.179–9.228 (dd, 1H, quin CH), 9.253–9.288 (dd, 1H, quin CH). 13C NMR (methanol-d4): 90.253 (quin C8), 124.038 (quin CH), 131.224(quin CH), 131.475 (quin C9/10), 132.070 (quin CH), 139.889 (quin C9/10), 147.113(quin CH), 148.440 (quin CH), 149.608 (quin CH). Analysis calculated for C9H7ClIN (dehydrated): C 37.08, H 2.42, N 4.80%; found: C 36.76, H 2.40, N 4.85%.

Refinement top

The water H atoms were located in a difference map and refined with O-H and H···H distance restraints of 0.84 (1) Å and 1.37 (2) Å, respectively, and with Uiso(H) = 1.5Ueq(O). The N-bound H atom was also located in a difference map and refind freely. C-bound H atoms were positioned geometrically (C-H = 0.93 Å) and allowed to ride on the parent atoms with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Asymmetric unit of 8-iodoquinolinium chloride dihydrate. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal structure of 8-iodoquinolinium chloride dihydrate, viewed approximately along the a axis. Dotted lines represent hydrogen bonds. H atoms have been omitted for clarity. Displacement ellipsoids are drawn at the 50% probability level.
8-Iodoquinolinium chloride dihydrate top
Crystal data top
C9H7IN+·Cl·2H2OF(000) = 632
Mr = 327.54Dx = 1.941 Mg m3
Monoclinic, P21/cMelting point: 388 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 8.9600 (18) ÅCell parameters from 9991 reflections
b = 17.580 (4) Åθ = 2.3–28.6°
c = 7.1700 (14) ŵ = 3.07 mm1
β = 97.13 (3)°T = 100 K
V = 1120.7 (4) Å3Block, brown
Z = 40.71 × 0.67 × 0.54 mm
Data collection top
Bruker SMART APEXII
diffractometer
2045 independent reflections
Radiation source: fine-focus sealed tube2040 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
ω scansθmax = 25.4°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2003)
h = 1010
Tmin = 0.219, Tmax = 0.288k = 2121
10655 measured reflectionsl = 88
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.019Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.046H atoms treated by a mixture of independent and constrained refinement
S = 1.26 w = 1/[σ2(Fo2) + (0.0437P)2 + 2.836P]
where P = (Fo2 + 2Fc2)/3
2045 reflections(Δ/σ)max = 0.001
143 parametersΔρmax = 0.79 e Å3
6 restraintsΔρmin = 0.65 e Å3
Crystal data top
C9H7IN+·Cl·2H2OV = 1120.7 (4) Å3
Mr = 327.54Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.9600 (18) ŵ = 3.07 mm1
b = 17.580 (4) ÅT = 100 K
c = 7.1700 (14) Å0.71 × 0.67 × 0.54 mm
β = 97.13 (3)°
Data collection top
Bruker SMART APEXII
diffractometer
2045 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2003)
2040 reflections with I > 2σ(I)
Tmin = 0.219, Tmax = 0.288Rint = 0.020
10655 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0196 restraints
wR(F2) = 0.046H atoms treated by a mixture of independent and constrained refinement
S = 1.26Δρmax = 0.79 e Å3
2045 reflectionsΔρmin = 0.65 e Å3
143 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
C20.1207 (3)0.35738 (15)0.0118 (4)0.0175 (6)
H20.09680.41000.02150.021*
C30.0078 (3)0.30408 (17)0.0595 (4)0.0187 (6)
H30.09180.31990.10350.022*
C40.0429 (3)0.22795 (15)0.0418 (4)0.0155 (5)
H40.03330.19090.07240.019*
C50.2333 (3)0.12642 (15)0.0433 (4)0.0170 (5)
H50.15910.08810.01550.020*
C60.3795 (3)0.10627 (15)0.1040 (4)0.0190 (6)
H60.40530.05410.11990.023*
C70.4923 (3)0.16273 (16)0.1430 (4)0.0169 (5)
H70.59320.14770.18210.020*
C80.4574 (3)0.23944 (15)0.1248 (4)0.0134 (5)
C90.3060 (3)0.26110 (14)0.0660 (3)0.0115 (5)
C100.1928 (3)0.20430 (15)0.0220 (4)0.0132 (5)
N10.2614 (3)0.33639 (13)0.0471 (3)0.0143 (5)
H10.326 (4)0.369 (2)0.080 (5)0.029 (10)*
Cl10.12024 (7)0.54723 (4)0.76556 (9)0.01743 (14)
I10.629687 (18)0.321563 (10)0.17166 (2)0.01562 (7)
O10.3734 (3)0.48091 (13)0.1171 (4)0.0404 (6)
H1A0.320 (4)0.506 (2)0.183 (5)0.061*
H1B0.363 (5)0.498 (2)0.008 (3)0.061*
O20.1749 (2)0.55620 (12)0.3282 (3)0.0240 (4)
H2A0.183 (4)0.559 (2)0.4461 (15)0.036*
H2B0.104 (3)0.5262 (17)0.294 (4)0.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0231 (14)0.0138 (13)0.0161 (13)0.0066 (11)0.0044 (11)0.0019 (10)
C30.0122 (13)0.0270 (15)0.0173 (14)0.0054 (11)0.0034 (11)0.0065 (11)
C40.0139 (13)0.0186 (13)0.0138 (12)0.0033 (10)0.0014 (10)0.0002 (10)
C50.0197 (14)0.0140 (13)0.0177 (13)0.0021 (11)0.0034 (11)0.0005 (10)
C60.0231 (15)0.0126 (13)0.0217 (14)0.0031 (11)0.0041 (11)0.0006 (11)
C70.0141 (13)0.0192 (13)0.0174 (13)0.0039 (11)0.0024 (10)0.0004 (11)
C80.0121 (12)0.0158 (13)0.0124 (12)0.0034 (10)0.0016 (10)0.0024 (10)
C90.0130 (12)0.0124 (12)0.0099 (11)0.0005 (10)0.0041 (9)0.0003 (9)
C100.0143 (13)0.0149 (12)0.0111 (12)0.0022 (10)0.0041 (10)0.0005 (10)
N10.0153 (12)0.0110 (11)0.0172 (12)0.0028 (9)0.0043 (9)0.0004 (9)
Cl10.0163 (3)0.0132 (3)0.0221 (3)0.0013 (2)0.0002 (2)0.0013 (2)
I10.01147 (10)0.01954 (11)0.01569 (11)0.00378 (6)0.00106 (7)0.00135 (6)
O10.0416 (15)0.0188 (12)0.0660 (18)0.0115 (10)0.0268 (14)0.0137 (11)
O20.0235 (11)0.0214 (11)0.0267 (11)0.0048 (8)0.0017 (9)0.0003 (9)
Geometric parameters (Å, º) top
C2—N11.331 (4)C7—C81.387 (4)
C2—C31.390 (4)C7—H70.95
C2—H20.95C8—C91.421 (4)
C3—C41.377 (4)C8—I12.110 (3)
C3—H30.95C9—N11.384 (3)
C4—C101.426 (4)C9—C101.430 (4)
C4—H40.95N1—H10.82 (4)
C5—C61.374 (4)O1—H1A0.836 (10)
C5—C101.420 (4)O1—H1B0.834 (10)
C5—H50.95O2—H2A0.840 (10)
C6—C71.419 (4)O2—H2B0.841 (10)
C6—H60.95
N1—C2—C3121.5 (2)C8—C7—H7119.5
N1—C2—H2119.2C6—C7—H7119.5
C3—C2—H2119.2C7—C8—C9119.0 (2)
C4—C3—C2118.8 (2)C7—C8—I1119.89 (19)
C4—C3—H3120.6C9—C8—I1121.09 (19)
C2—C3—H3120.6N1—C9—C8122.6 (2)
C3—C4—C10120.6 (2)N1—C9—C10117.2 (2)
C3—C4—H4119.7C8—C9—C10120.2 (2)
C10—C4—H4119.7C5—C10—C4122.3 (2)
C6—C5—C10120.2 (2)C5—C10—C9119.0 (2)
C6—C5—H5119.9C4—C10—C9118.8 (2)
C10—C5—H5119.9C2—N1—C9123.1 (2)
C5—C6—C7120.6 (3)C2—N1—H1120 (3)
C5—C6—H6119.7C9—N1—H1117 (3)
C7—C6—H6119.7H1A—O1—H1B110 (2)
C8—C7—C6121.0 (2)H2A—O2—H2B107 (2)
N1—C2—C3—C41.1 (4)C6—C5—C10—C90.5 (4)
C2—C3—C4—C100.8 (4)C3—C4—C10—C5179.6 (3)
C10—C5—C6—C71.1 (4)C3—C4—C10—C90.4 (4)
C5—C6—C7—C81.4 (4)N1—C9—C10—C5178.7 (2)
C6—C7—C8—C90.0 (4)C8—C9—C10—C51.8 (4)
C6—C7—C8—I1177.1 (2)N1—C9—C10—C41.3 (3)
C7—C8—C9—N1179.0 (2)C8—C9—C10—C4178.2 (2)
I1—C8—C9—N13.9 (3)C3—C2—N1—C90.2 (4)
C7—C8—C9—C101.6 (4)C8—C9—N1—C2178.4 (2)
I1—C8—C9—C10175.50 (18)C10—C9—N1—C21.0 (4)
C6—C5—C10—C4179.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.82 (4)2.03 (4)2.755 (3)147 (3)
N1—H1···I10.82 (4)2.85 (4)3.320 (2)119 (3)
O1—H1A···O20.84 (1)1.98 (1)2.807 (3)173 (5)
O1—H1B···Cl1i0.83 (1)2.75 (3)3.382 (3)134 (4)
O2—H2A···Cl10.84 (1)2.44 (2)3.237 (2)160 (3)
O2—H2B···Cl1ii0.84 (1)2.38 (1)3.211 (2)170 (3)
Symmetry codes: (i) x, y, z1; (ii) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC9H7IN+·Cl·2H2O
Mr327.54
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)8.9600 (18), 17.580 (4), 7.1700 (14)
β (°) 97.13 (3)
V3)1120.7 (4)
Z4
Radiation typeMo Kα
µ (mm1)3.07
Crystal size (mm)0.71 × 0.67 × 0.54
Data collection
DiffractometerBruker SMART APEXII
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2003)
Tmin, Tmax0.219, 0.288
No. of measured, independent and
observed [I > 2σ(I)] reflections
10655, 2045, 2040
Rint0.020
(sin θ/λ)max1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.019, 0.046, 1.26
No. of reflections2045
No. of parameters143
No. of restraints6
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.79, 0.65

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXTL (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.82 (4)2.03 (4)2.755 (3)147 (3)
N1—H1···I10.82 (4)2.85 (4)3.320 (2)119 (3)
O1—H1A···O20.84 (1)1.975 (12)2.807 (3)173 (5)
O1—H1B···Cl1i0.83 (1)2.75 (3)3.382 (3)134 (4)
O2—H2A···Cl10.84 (1)2.435 (16)3.237 (2)160 (3)
O2—H2B···Cl1ii0.84 (1)2.379 (12)3.211 (2)170 (3)
Symmetry codes: (i) x, y, z1; (ii) x, y+1, z+1.
 

Acknowledgements

This work was supported by funding from the South Dakota 2010 Initiative, Center for Research and Development of Light-Activated Materials. Purchase of the X-ray diffractometer was made possible with funds from the National Science Foundation (EPS-0554609).

References

First citationBruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationJaniak, C. (2000). J. Chem. Soc. Dalton Trans. pp. 3885–3896.  Web of Science CrossRef Google Scholar
First citationLucas, H. J. & Kennedy, E. R. (1943). Org. Synth. Coll. Vol. II, pp. 351–352.  Google Scholar
First citationMacrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSandmeyer, T. (1884). Ber. Dtsch. Chem. Ges. 17, 1633–1635.  CrossRef Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSon, J.-H. & Hoefelmeyer, J. D. (2008). Acta Cryst. E64, o2077.  Web of Science CrossRef IUCr Journals Google Scholar

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