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Redetermined structure of β-DL-me­thio­nine at 105 K: an example of the importance of freely refining the positions of the amino-group H atoms

aDepartment of Chemistry, University of Oslo, PO Box 1033 Blindern, N-0315 Oslo, Norway
*Correspondence e-mail: c.h.gorbitz@kjemi.uio.no

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 23 September 2014; accepted 8 October 2014; online 15 October 2014)

Diffraction data were taken from the contribution named `β-DL-Me­thio­nine at 105 K′ by Alagar et al. [Acta Cryst. (2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]). E61, o1165–o1167]. Refinement of the coordinates of the three amino H atoms, previously constrained to an idealized geometry, shows that the amino group is in fact rotated 13.5° from the perfectly staggered orientation. This apparently modest change has a profound impact on the calculated hydrogen-bond geometries.

1. Chemical context

Upon comparing the hydrogen-bond geometries of the high-temperature α-phase of the amino acid racemate DL-me­thio­nine (Görbitz et al., 2014[Görbitz, C. H., Qi, L., Mai, N. T. K. & Kristiansen, H. (2014). Acta Cryst. E70, 337-340.]) with the best published structure of the β-phase [Alagar et al., 2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]; refcode DLMETA05 in the Cambridge Structural Database (CSD), Version 5.35; Allen, 2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]], we noted that H⋯O distances surprisingly appeared to get shorter at 340 K than at 105 K. This was judged to be an artefact resulting from different ways of handling the amino H atoms. Alagar et al. (2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]) used an idealized geometry and a perfectly staggered orientation for this group in their refinement; while we found a 14° counterclockwise rotation (for the L-enanti­omer) that served to give three shorter and more linear inter­actions. The experimental and structural data of Alagar et al. (2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]), with coordinates for the D-enanti­omer as the asymmetric unit, were subsequently downloaded and refined again with free amino H atoms, thus increasing the number of parameters from 82 (nine parameters for nine atoms + scale factor) to 91. In the improved structural model displayed in Fig. 1[link] [R(F) = 0.0377 versus 0.411 and wR(F2) = 0.0918 versus 0.1001], the amino group is shifted slightly away from the staggered orientation through a 13.5° clockwise rotation (for the D-enanti­omer), Table 1[link].

[Scheme 1]

Table 1
Selected torsion angles (°)

N1—C2—C3—C4 54.4 (2) C1—C2—N1—H1 46.5 (17)
C1—C2—C3—C4 173.53 (15) C1—C2—N1—H2 −75.3 (15)
C2—C3—C4—S1 179.23 (12) C1—C2—N1—H3 167.4 (15)
C3—C4—S1—C5 175.03 (14)    
[Figure 1]
Figure 1
(a) The structure of DL-me­thio­nine, (I)[link], viewed approximately along the N1—C2 bond vector, with 50% probability thermal displacement ellipsoids. The racemate contains mol­ecules of both hands; the one depicted here is the D-enanti­omer. Carboxyl­ate groups of three neighboring amino acids accepting hydrogen bonds are shown in a lighter tone. O2i is at (−x, y + [{1\over 2}], −z + [{1\over 2}]), O2ii at (x + [{1\over 2}], −y, z) and Oiii at (x + [{1\over 2}], −y + 1, z), see Table 2[link]. Compared to the previously published structure shown in capped sticks representation in (b) (Alagar et al., 2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]), the amino group has been rotated clockwise by about 13.5° to give shorter and more linear hydrogen bonds.

2. Supra­molecular features

The hydrogen-bond geometries listed in Table 2[link] show that the free refinement of amino-group H atoms gives close to linear N—H⋯O inter­actions with substanti­ally shorter H⋯O distances. There are no significant changes for geometric parameters involving only C, N and O atoms. This example demonstrates that in order not to unduly bias the statistics of hydrogen-bond geometries in the CSD, it is imperative that H atoms of amino groups and other hydrogen-bond donating functional groups whenever possible are refined in a normal manner and not constrained to theoretical positions. The data set used here (Alagar et al., 2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]) is of good, but not excellent quality. Nevertheless, H atoms can be refined with decent accuracy [standard uncertainties (s.u.'s) = 0.03 Å for N—H distances], allowing experimental determination of hydrogen-bond geometries. In the event that s.u.'s get much higher and/or N—H distances are clearly unreasonably short or long, a rigid rotation refinement of the group (e.g. by an AFIX 37 command in SHELXL; Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) should be performed. The results of such a refinement for (I)[link], which adds just a single refinement parameter compared to DLMETA05, but reaches the same R factor as for (I)[link], are included in Table 2[link]. The listed values are very close to those of the unconstrained refinement, but are obviously devoid of s.u.'s for geometric parameters involving H atoms.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A Parameter DLMETA05a (I)-rigidb (I)
N1—H1⋯O2i N—H 0.89 0.91 0.88 (3)
  H⋯O 1.93 1.88 1.91 (3)
  N⋯O 2.788 (2) 2.787 (2) 2.788 (2)
  N—H⋯O 162 173 174 (2)
N1—H2⋯O1ii N—H 0.89 0.91 0.94 (3)
  H⋯O 2.02 1.92 1.89 (3)
  N⋯O 2.814 (2) 2.815 (2) 2.815 (2)
  N—H⋯O 148 167 169 (2)
N1—H3⋯O1iii N—H 0.89 0.91 0.92 (3)
  H⋯O 2.02 1.91 1.91 (3)
  N⋯O 2.794 (2) 2.795 (2) 2.795 (2)
  N—H⋯O 144 163 161 (2)
Symmetry codes: (i) −x, y + [{1\over 2}], −z + [{1\over 2}]; (ii) x + [{1\over 2}], −y, z; (iii) x + [{1\over 2}], −y + 1, z. Notes: (a) Alagar et al. (2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]), 82 parameters; atoms H1, H2 and H3 were called H1A, H1B and H1C, respectively, by the original authors; the labels used in the CSD entry DLMETA05 have been retained here. (b) Rigid rotation refinement of (I)[link], 83 parameters. 0.91 Å is the standard N—H bond length in SHELXL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) at 105 K.

Under other circumstances restraints on covalent geometry may be employed. Accordingly, we have found that it is often useful to restrain O—H bond distances and H—O—H bond angles (through the 1–3 distances) during refinement of water mol­ecules in crystal hydrates. For a single mol­ecule with atom labels H1W—O1W—H2W, the appropriate SHELXL commands would be DFIX 0.85 0.02 O1W H1W O1W H2W and DFIX 1.35 0.03 H1W H2W (the s.u.'s of 0.02 and 0.03 Å being subject to discussion). Similar approaches may be used for groups like –OH and –NH2 for which AFIX 37 commands (or equivalent) are not applicable.

3. Experimental

For crystallization details, see Alagar et al. (2005[Alagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165-o1167.]). Crystal data, data collection and structure refinement details are summarized in Table 3[link].

Table 3
Experimental details

Crystal data
Chemical formula C5H11NO2S
Mr 149.21
Crystal system, space group Monoclinic, I2/a
Temperature (K) 105
a, b, c (Å) 9.877 (2), 4.6915 (10), 32.603 (6)
β (°) 106.25 (1)
V3) 1450.4 (5)
Z 8
Radiation type Mo Kα
μ (mm−1) 0.38
Crystal size (mm) 0.32 × 0.24 × 0.22
 
Data collection
Diffractometer Bruker SMART CCD area detector
Absorption correction Multi-scan (SADABS; Bruker, 1998[Bruker (1998). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.85, 0.92
No. of measured, independent and observed [I > 2σ(I)] reflections 6469, 1436, 1373
Rint 0.023
(sin θ/λ)max−1) 0.623
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.092, 1.26
No. of reflections 1436
No. of parameters 91
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.35, −0.23
Computer programs: SMART-NT and SAINT-NT (Bruker, 1999[Bruker (1999). SMART-NT and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS97, SHELXL2013 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Coordinates were refined for amino H atoms; other H atoms were positioned with idealized geometry, with fixed C—H = 0.98 (meth­yl), 0.99 (methyl­ene) or 1.00 Å (methine). Uiso(H) values were set at 1.2Ueq of the carrier atom or at 1.5Ueq for methyl and amino groups.

Supporting information


Chemical context [Appropriate title?] top

Upon comparing the hydrogen-bond geometries of the high-temperature α-phase of the amino acid racemate DL-me­thio­nine (Görbitz et al., 2014) with the best published structure of the β-phase [Alagar et al., 2005; refcode DLMETA05 in the Cambridge Structural Database (CSD), Version 5.35; Allen, 2002], we noted that H···O distances surprisingly appeared to get shorter at 340 K than at 105 K. This was judged to be an artefact resulting from different ways of handling the amino H atoms. Alagar et al. (2005) used an idealized geometry and a perfectly staggered orientation for this group in their refinement; while we found a ~14° counterclockwise rotation (for the L-enanti­omer) that served to give three shorter and more linear inter­actions. The experimental and structural data of Alagar et al. (2005), with coordinates for the D-enanti­omer as the asymmetric unit, were subsequently downloaded and refined again with free amino H atoms, thus increasing the number of parameters from 82 (nine parameters for nine atoms + scale factor) to 91. In the improved structural model displayed in Fig. 1 [R(F) = 0.0377 versus 0.411 and wR(F2) = 0.0918 versus 0.1001], the amino group is shifted slightly away from the staggered orientation through a ~13.5° clockwise rotation (for the D-enanti­omer). As seen from Table 1, this change gives close to linear N—H···O inter­actions with substanti­ally shorter H···O distances. There are no significant changes for geometric parameters involving only C, N and O atoms. Selected torsion angles are given in Table 2.

Supra­molecular features [Appropriate title?] top

This example demonstrates that in order not to unduly bias the statistics of hydrogen-bond geometries in the CSD, it is imperative that H atoms of amino groups and other hydrogen-bond donating functional groups whenever possible are refined in a normal manner and not constrained to theoretical positions. The data set used here (Alagar et al., 2005) is of good, but not excellent quality. Nevertheless, H atoms can be refined with decent accuracy [standard uncertainties (s.u.'s) = 0.03 Å for N—H distances], allowing experimental determination of hydrogen-bond geometries. In the event that s.u.'s get much higher and/or N—H distances are clearly unreasonably short or long, a rigid rotation refinement of the group (e.g. by an AFIX 37 command in SHELXL; Sheldrick, 2008) should be performed. The results of such a refinement for (I), which adds just a single refinement parameter compared to DLMETA05, but reaches the same R factor as for (I), are included in Table 3. The listed values are very close to those of the unconstrained refinement, but are obviously devoid of s.u.'s for geometric parameters involving H atoms.

Under other circumstances restraints on covalent geometry may be employed. Accordingly, we have found that it is often useful to restrain O—H bond distances and H—O—H bond angles (through the 1–3 distances) during refinement of water molecules in crystal hydrates. For a single molecule with atom labels H1W—O1W—H2W, the appropriate SHELXL commands would be DFIX 0.85 0.02 O1W H1W O1W H2W and DFIX 1.35 0.03 H1W H2W (the s.u.'s of 0.02 and 0.03 Å being subject to discussion). Similar approaches may be used for groups like –OH and –NH2 for which AFIX 37 commands (or equivalent) are not applicable.

Synthesis and crystallization top

For synthesis detaisl, see Alagar et al. (2005).

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 3. Coordinates were refined for amino H atoms; other H atoms were positioned with idealized geometry, with fixed C—H = 0.98 (methyl), 0.99 (methyl­ene) or 1.00 Å (methine). Uiso(H) values were set at 1.2Ueq of the carrier atom or at 1.5Ueq for methyl and amino groups.

Related literature top

For related literature, see: Alagar et al. (2005); Allen (2002); Görbitz et al. (2014); Sheldrick (2008).

Computing details top

Data collection: SMART-NT (Bruker, 1999); cell refinement: SAINT-NT (Bruker, 1999); data reduction: SAINT-NT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008).

Figures top
(a) The structure of DL-methionine, (I), viewed approximately along the N1—C2 bond vector, with 50% probability thermal displacement ellipsoids. The racemate contains molecules of both hands; the one depicted here is the D-enantiomer. Carboxylate groups of three neighboring amino acids accepting hydrogen bonds are shown in a lighter tone. O2i is at (-x, y+1/2, -z+1/2, O2ii at (x+1/2, -y, z) and Oiii at (x+1/2, -y+1, z), see Table 1. Compared to the previously published structure shown in capped sticks representation in (b) (Alagar et al., 2005), the amino group has been rotated clockwise by about 13.5° to give shorter and more linear hydrogen bonds.
2-Amino-4-(methylsulfanyl)butanoic acid top
Crystal data top
C5H11NO2SF(000) = 640
Mr = 149.21Dx = 1.367 Mg m3
Monoclinic, I2/aMo Kα radiation, λ = 0.71073 Å
a = 9.877 (2) ÅCell parameters from 1012 reflections
b = 4.6915 (10) Åθ = 2.6–26.1°
c = 32.603 (6) ŵ = 0.38 mm1
β = 106.25 (1)°T = 105 K
V = 1450.4 (5) Å3Block, colourless
Z = 80.32 × 0.24 × 0.22 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
1436 independent reflections
Radiation source: fine-focus sealed tube1373 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 8.3 pixels mm-1θmax = 26.3°, θmin = 2.6°
Sets of exposures each taken over 0.5° ω rotation scansh = 1211
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
k = 05
Tmin = 0.85, Tmax = 0.92l = 040
6469 measured reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.092 w = 1/[σ2(Fo2) + (0.0233P)2 + 2.4782P]
where P = (Fo2 + 2Fc2)/3
S = 1.26(Δ/σ)max = 0.001
1436 reflectionsΔρmax = 0.35 e Å3
91 parametersΔρmin = 0.23 e Å3
Crystal data top
C5H11NO2SV = 1450.4 (5) Å3
Mr = 149.21Z = 8
Monoclinic, I2/aMo Kα radiation
a = 9.877 (2) ŵ = 0.38 mm1
b = 4.6915 (10) ÅT = 105 K
c = 32.603 (6) Å0.32 × 0.24 × 0.22 mm
β = 106.25 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
1436 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
1373 reflections with I > 2σ(I)
Tmin = 0.85, Tmax = 0.92Rint = 0.023
6469 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.092H atoms treated by a mixture of independent and constrained refinement
S = 1.26Δρmax = 0.35 e Å3
1436 reflectionsΔρmin = 0.23 e Å3
91 parameters
Special details top

Experimental. Diffraction data and experimental conditions are taken from Alagar et al. (2005), CSD refcode DLMETA05.

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 amino H atom coordinates.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.39652 (6)0.15681 (12)0.44292 (2)0.03291 (18)
O10.14523 (13)0.2025 (3)0.31403 (4)0.0240 (3)
O20.01841 (13)0.0810 (3)0.28411 (4)0.0216 (3)
N10.19296 (17)0.3000 (3)0.29733 (5)0.0193 (3)
H10.142 (3)0.332 (5)0.2710 (8)0.029*
H20.238 (2)0.122 (6)0.2999 (7)0.029*
H30.263 (2)0.436 (5)0.3054 (7)0.029*
C10.03289 (18)0.1301 (4)0.30562 (5)0.0185 (4)
C20.09967 (18)0.3087 (4)0.32589 (5)0.0183 (4)
H40.07190.51030.32940.022*
C30.17639 (19)0.1831 (4)0.36982 (5)0.0214 (4)
H50.11480.20380.38890.026*
H60.19110.02320.36640.026*
C40.3196 (2)0.3214 (4)0.39143 (6)0.0246 (4)
H70.30680.52810.39520.030*
H80.38370.29730.37310.030*
C50.5659 (2)0.3326 (5)0.45830 (7)0.0350 (5)
H90.62080.26270.48640.053*
H100.61690.29160.43710.053*
H110.55210.53880.45970.053*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0351 (3)0.0337 (3)0.0231 (3)0.0067 (2)0.0031 (2)0.0074 (2)
O10.0225 (7)0.0168 (6)0.0333 (7)0.0012 (5)0.0089 (5)0.0003 (5)
O20.0253 (7)0.0156 (6)0.0222 (6)0.0010 (5)0.0037 (5)0.0028 (5)
N10.0207 (7)0.0169 (8)0.0190 (7)0.0010 (6)0.0035 (6)0.0008 (6)
C10.0213 (8)0.0138 (8)0.0181 (8)0.0006 (7)0.0019 (7)0.0034 (6)
C20.0212 (8)0.0128 (8)0.0208 (8)0.0005 (7)0.0059 (7)0.0008 (7)
C30.0248 (9)0.0186 (9)0.0197 (8)0.0008 (7)0.0043 (7)0.0002 (7)
C40.0273 (10)0.0216 (9)0.0213 (9)0.0016 (8)0.0007 (7)0.0017 (7)
C50.0309 (11)0.0416 (13)0.0272 (10)0.0024 (9)0.0008 (8)0.0012 (9)
Geometric parameters (Å, º) top
S1—C51.806 (2)C2—H41.0000
S1—C41.8104 (19)C3—C41.536 (2)
O1—C11.262 (2)C3—H50.9900
O2—C11.245 (2)C3—H60.9900
N1—C21.483 (2)C4—H70.9900
N1—H10.88 (3)C4—H80.9900
N1—H20.94 (3)C5—H90.9800
N1—H30.92 (3)C5—H100.9800
C1—C21.539 (2)C5—H110.9800
C2—C31.538 (2)
C5—S1—C4100.27 (10)C4—C3—H5108.6
C2—N1—H1108.9 (15)C2—C3—H5108.6
C2—N1—H2109.2 (14)C4—C3—H6108.6
H1—N1—H2111 (2)C2—C3—H6108.6
C2—N1—H3110.5 (14)H5—C3—H6107.6
H1—N1—H3110 (2)C3—C4—S1109.80 (13)
H2—N1—H3107 (2)C3—C4—H7109.7
O2—C1—O1125.67 (17)S1—C4—H7109.7
O2—C1—C2117.19 (15)C3—C4—H8109.7
O1—C1—C2117.03 (15)S1—C4—H8109.7
N1—C2—C3110.09 (14)H7—C4—H8108.2
N1—C2—C1108.59 (14)S1—C5—H9109.5
C3—C2—C1109.25 (14)S1—C5—H10109.5
N1—C2—H4109.6H9—C5—H10109.5
C3—C2—H4109.6S1—C5—H11109.5
C1—C2—H4109.6H9—C5—H11109.5
C4—C3—C2114.57 (15)H10—C5—H11109.5
N1—C2—C3—C454.4 (2)O2—C1—C2—C387.60 (18)
C1—C2—C3—C4173.53 (15)O1—C1—C2—C388.98 (18)
C2—C3—C4—S1179.23 (12)C1—C2—N1—H146.5 (17)
C3—C4—S1—C5175.03 (14)C1—C2—N1—H275.3 (15)
O2—C1—C2—N132.5 (2)C1—C2—N1—H3167.4 (15)
O1—C1—C2—N1150.93 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.88 (3)1.91 (3)2.788 (2)175 (3)
N1—H2···O1ii0.94 (3)1.89 (3)2.815 (2)169 (2)
N1—H3···O1iii0.92 (2)1.91 (2)2.795 (2)161 (2)
C2—H4···O2iv1.002.433.244 (2)138
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x+1/2, y, z; (iii) x+1/2, y+1, z; (iv) x, y+1, z.
Selected torsion angles (º) top
N1—C2—C3—C454.4 (2)C1—C2—N1—H146.5 (17)
C1—C2—C3—C4173.53 (15)C1—C2—N1—H275.3 (15)
C2—C3—C4—S1179.23 (12)C1—C2—N1—H3167.4 (15)
C3—C4—S1—C5175.03 (14)
Hydrogen-bond geometry (Å, °) top
D—H···AParameterDLMETA05a(I)-rigidb(I)
N1—H1···O2iN—H0.890.910.88 (3)
H···O1.931.881.91 (3)
N···O2.788 (2)2.787 (2)2.788 (2)
N—H···O162173174 (2)
N1—H2···O1iiN—H0.890.910.94 (3)
H···O2.021.921.89 (3)
N···O2.814 (2)2.815 (2)2.815 (2)
N—H···O148167169 (2)
N1—H3···O1iiiN—H0.890.910.92 (3)
H···O2.021.911.91 (3)
N···O2.794 (2)2.795 (2)2.795 (2)
N—H···O144163161 (2)
Symmetry codes: (i) -x, y+1/2, -z+1/2; (ii) x+1/2, -y, z; (iii) x+1/2, -y+1, z. Notes: (a) Alagar et al. (2005), 82 parameters; atoms H1, H2 and H3 were called H1A, H1B and H1C, respectively, by the original authors; the labels used in the CSD entry DLMETA05 have been retained here. (b) Rigid rotation refinement of (I), 83 parameters. 0.91 Å is the standard N—H bond length in SHELXL (Sheldrick, 2008) at 105 K.

Experimental details

Crystal data
Chemical formulaC5H11NO2S
Mr149.21
Crystal system, space groupMonoclinic, I2/a
Temperature (K)105
a, b, c (Å)9.877 (2), 4.6915 (10), 32.603 (6)
β (°) 106.25 (1)
V3)1450.4 (5)
Z8
Radiation typeMo Kα
µ (mm1)0.38
Crystal size (mm)0.32 × 0.24 × 0.22
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1998)
Tmin, Tmax0.85, 0.92
No. of measured, independent and
observed [I > 2σ(I)] reflections
6469, 1436, 1373
Rint0.023
(sin θ/λ)max1)0.623
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.092, 1.26
No. of reflections1436
No. of parameters91
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.35, 0.23

Computer programs: SMART-NT (Bruker, 1999), SAINT-NT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

References

First citationAlagar, M., Krishnakumar, R. V., Mostad, A. & Natarajan, S. (2005). Acta Cryst. E61, o1165–o1167.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationAllen, F. H. (2002). Acta Cryst. B58, 380–388.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationBruker (1998). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (1999). SMART-NT and SAINT-NT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationGörbitz, C. H., Qi, L., Mai, N. T. K. & Kristiansen, H. (2014). Acta Cryst. E70, 337–340.  CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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