organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

3-Carb­­oxy-2-meth­oxy­phenyl­boronic acid

aWarsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland
*Correspondence e-mail: serek@ch.pw.edu.pl

(Received 9 September 2008; accepted 15 September 2008; online 20 September 2008)

The mol­ecular structure of the title compound, 3-COOH-2-CH3O—C6H3B(OH)2 or C8H9BO5, is stabilized in part due to the presence of an intra­molecular O—H⋯O hydrogen bond. In the crystal structure, mol­ecules are linked by inter­molecular O—H⋯O hydrogen bonds, generating a two-dimensional sheet structure aligned parallel to the (11[\overline{2}]) plane.

Related literature

For structures of other carboxy­phenyl­boronic acids, see: SeethaLekshmi & Pedireddi (2007[SeethaLekshmi, N. & Pedireddi, V. R. (2007). Cryst. Growth Des. 7, 944-949.]); Soundararajan et al. (1993[Soundararajan, S., Duesler, E. N. & Hageman, J. H. (1993). Acta Cryst. C49, 690-693.]). For the application of carboxy­phenyl­boronic acids in crystal engineering, see: (Aakeröy et al., 2005[Aakeröy, C. B., Desper, J. & Levin, B. (2005). CrystEngComm, 7, 102-107.]; SeethaLekshmi & Pedireddi, 2006[SeethaLekshmi, N. & Pedireddi, V. R. (2006). Inorg. Chem. 45, 2400-2402.]). For structural characterization of related ortho-alk­oxy aryl­boronic acids, see: Dabrowski et al. (2006[Dabrowski, M., Lulinski, S., Serwatowski, J. & Szczerbinska, M. (2006). Acta Cryst. C62, o702-o704.]); Dąbrowski et al. (2008[Dąbrowski, M., Luliński, S. & Serwatowski, J. (2008). Acta Cryst. E64, o414-o415.]); Yang et al. (2005[Yang, Y., Escobedo, J. O., Wong, A., Schowalter, C. M., Touchy, M. C., Jiao, L., Crowe, W. E., Fronczek, F. R. & Strongin, R. M. (2005). J. Org. Chem. 70, 6907-6912.]). For the synthesis of the title compound, see: (Kurach et al., 2008[Kurach, P., Luliński, S. & Serwatowski, J. (2008). Eur. J. Org. Chem. 3171-3178.]).

[Scheme 1]

Experimental

Crystal data
  • C8H9BO5

  • Mr = 195.96

  • Triclinic, [P \overline 1]

  • a = 4.8451 (5) Å

  • b = 7.7564 (7) Å

  • c = 12.1064 (9) Å

  • α = 79.476 (7)°

  • β = 79.575 (7)°

  • γ = 76.125 (8)°

  • V = 429.75 (7) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100 (2) K

  • 0.32 × 0.20 × 0.14 mm

Data collection
  • Kuma KM4 CCD diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction 2005[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd., Abingdon, Oxfordshire, England.]) Tmin = 0.95, Tmax = 0.98

  • 12229 measured reflections

  • 2106 independent reflections

  • 1526 reflections with I > 2σ(I)

  • Rint = 0.018

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.101

  • S = 1.05

  • 2106 reflections

  • 163 parameters

  • All H-atom parameters refined

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Selected geometric parameters (Å, °)

B1—O2 1.3443 (15)
B1—O3 1.3461 (16)
B1—C9 1.5661 (17)
C6—O8 1.2607 (13)
C6—O7 1.3044 (14)
O2—B1—C9—C14 18.65 (16)
C5—O4—C10—C9 93.35 (12)
O8—C6—C11—C10 177.57 (10)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O3i 0.802 (19) 1.96 (2) 2.7572 (13) 172.6 (18)
O3—H3⋯O4 0.84 (2) 2.06 (2) 2.7283 (12) 136.8 (19)
O3—H3⋯O2ii 0.84 (2) 2.45 (2) 3.0538 (14) 130.2 (19)
O7—H8⋯O8iii 1.03 (2) 1.60 (2) 2.6255 (11) 177.0 (16)
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) x-1, y, z; (iii) -x, -y+1, -z.

Data collection: CrysAlis CCD (Oxford Diffraction (2005[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd., Abingdon, Oxfordshire, England.]); cell refinement: CrysAlis RED (Oxford Diffraction (2005[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd., Abingdon, Oxfordshire, England.]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

The presence of a carboxyl group in a molecule of arylboronic acid provides an increased potential for extended supramolecular organization (SeethaLekshmi & Pedireddi, 2007). The promising properties of carboxyphenylboronic acids in crystal engineering (Aakeröy et al., 2005; SeethaLekshmi & Pedireddi, 2006) prompted us to determine the structure of the title compound, (I).

The molecular structure of (I) shows the boronic groups possesses an exo-endo conformation and is slightly twisted with respect to the benzene ring (Table 1). The methoxy group is twisted almost perpendicularly with respect to the aromatic ring. The endo-oriented OH group is engaged in an intramolecular O—H···O hydrogen bonds with the methoxy O atom, resulting in the formation of a six-membered ring. This motif is generally typical of structures of ortho-alkoxyarylboronic acids (Yang et al., 2005; Dąbrowski et al., 2006). The carboxyl group is almost coplanar with respect to the benzene ring. The molecules are linked via almost linear O—H···O bridges in a "head-to-head, tail-to-tail" fashion, i.e., equivalent groups interact with each other forming two alternate centrosymmetric dimeric motifs, Table 2. As a result, an infinite, zigzag chain is formed (Fig. 2). The chain structure resembles the situation found for the related 2-methoxy-1,3-phenylenediboronic acid (Dąbrowski et al., 2008), where single molecules are linked via homomeric (SeethaLekshmi & Pedireddi, 2007) hydrogen-bonding interactions of non-equivalent boronic groups.

The 1D supramolecular architecture extends through cross-linking weak O—H···O bonds between twisted boronic groups. As a result a 2D array is formed, aligned parallel to the (11–2) plane. In conclusion, the intermolecular hydrogen-bonding interactions of boronic and carboxyl groups result in the formation of the infinite chain structure. Chains are interconnected by means of weaker hydrogen-bonds, thus forming the layer structure.

Related literature top

For structures of other carboxyphenylboronic acids, see: SeethaLekshmi & Pedireddi (2007); Soundararajan et al. (1993). For the application of carboxyphenylboronic acids in crystal engineering, see: (Aakeröy et al., 2005; SeethaLekshmi & Pedireddi, 2006). For structural characterization of related ortho-alkoxy arylboronic acids, see: Dabrowski et al. (2006); Dąbrowski et al. (2008); Yang et al. (2005). For the synthesis of the title compound, see: (Kurach et al., 2008).

Experimental top

The compund was prepared according to the published procedure (Kurach et al., 2008). Crystals suitable for single-crystal X-ray diffraction analysis were grown by slow evaporation of a solution of the acid (0.15 g) in ethyl acetate/acetone (10 ml, 1:1).

Refinement top

All hydrogen atoms were located in difference syntheses and refined freely so that O-H = 0.802 (19) - 1.03 (2) Å and C-H = 0.942 (17) - 1.029 (17) Å.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction (2005); cell refinement: CrysAlis RED (Oxford Diffraction (2005); data reduction: CrysAlis RED (Oxford Diffraction (2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing the atom-labelling scheme. The intramolecular hydrogen bond is shown as a dashed lines. Displacement ellipsoids for all non-H atoms are drawn at the 50% probability level.
[Figure 2] Fig. 2. The hydrogen-bonding pattern for (I). Hydrogen bonds are shown as dashed lines.
'3-carboxy-2-methoxyphenylboronic acid' top
Crystal data top
C8H9BO5V = 429.75 (7) Å3
Mr = 195.96Z = 2
Triclinic, P1F(000) = 204
Hall symbol: -P 1Dx = 1.514 Mg m3
a = 4.8451 (5) ÅMelting point: 429-432 K K
b = 7.7564 (7) ÅMo Kα radiation, λ = 0.71073 Å
c = 12.1064 (9) ŵ = 0.12 mm1
α = 79.476 (7)°T = 100 K
β = 79.575 (7)°Prismatic, colourless
γ = 76.125 (8)°0.32 × 0.20 × 0.14 mm
Data collection top
Kuma KM4 CCD
diffractometer
2106 independent reflections
Radiation source: fine-focus sealed tube1526 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.018
Detector resolution: 8.6479 pixels mm-1θmax = 28.6°, θmin = 3.0°
ω scanh = 66
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction 2005)
k = 1010
Tmin = 0.95, Tmax = 0.98l = 1616
12229 measured reflections
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101All H-atom parameters refined
S = 1.05 w = 1/[σ^2^(Fo^2^) + (0.0643P)^2^]
where P = (Fo^2^ + 2Fc^2^)/3
2106 reflections(Δ/σ)max = 0.001
163 parametersΔρmax = 0.35 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C8H9BO5γ = 76.125 (8)°
Mr = 195.96V = 429.75 (7) Å3
Triclinic, P1Z = 2
a = 4.8451 (5) ÅMo Kα radiation
b = 7.7564 (7) ŵ = 0.12 mm1
c = 12.1064 (9) ÅT = 100 K
α = 79.476 (7)°0.32 × 0.20 × 0.14 mm
β = 79.575 (7)°
Data collection top
Kuma KM4 CCD
diffractometer
2106 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction 2005)
1526 reflections with I > 2σ(I)
Tmin = 0.95, Tmax = 0.98Rint = 0.018
12229 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.101All H-atom parameters refined
S = 1.05Δρmax = 0.35 e Å3
2106 reflectionsΔρmin = 0.26 e Å3
163 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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
B10.5522 (3)0.79514 (18)0.40716 (11)0.0168 (3)
O20.77114 (19)0.78932 (13)0.46290 (7)0.0247 (2)
O30.3223 (2)0.93263 (13)0.41255 (8)0.0295 (3)
O40.20761 (17)0.81061 (11)0.23177 (7)0.0181 (2)
C50.3211 (3)0.92945 (19)0.13926 (12)0.0300 (3)
C60.2362 (2)0.50663 (16)0.11119 (9)0.0165 (3)
O70.04150 (18)0.65037 (11)0.08598 (7)0.0199 (2)
O80.27658 (18)0.36943 (11)0.06341 (7)0.0216 (2)
C90.5714 (2)0.63677 (16)0.34035 (9)0.0168 (3)
C100.3987 (2)0.65025 (15)0.25686 (9)0.0147 (3)
C110.4152 (2)0.50426 (15)0.20035 (9)0.0162 (3)
C120.6083 (3)0.34441 (17)0.22948 (10)0.0200 (3)
C130.7810 (3)0.32923 (17)0.31153 (11)0.0232 (3)
C140.7620 (3)0.47419 (17)0.36588 (10)0.0204 (3)
H20.729 (4)0.869 (2)0.5008 (16)0.052 (5)*
H30.204 (5)0.903 (3)0.3808 (19)0.083 (7)*
H5A0.506 (4)0.956 (2)0.1564 (13)0.043 (4)*
H5B0.187 (3)1.040 (2)0.1310 (13)0.043 (4)*
H5C0.361 (3)0.8735 (19)0.0712 (13)0.031 (4)*
H80.080 (4)0.638 (2)0.0276 (16)0.067 (6)*
H120.612 (3)0.245 (2)0.1950 (12)0.025 (4)*
H130.906 (3)0.217 (2)0.3314 (12)0.030 (4)*
H140.878 (3)0.4602 (18)0.4239 (11)0.024 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
B10.0178 (7)0.0218 (7)0.0127 (6)0.0063 (5)0.0035 (5)0.0036 (5)
O20.0229 (5)0.0308 (5)0.0255 (5)0.0031 (4)0.0095 (4)0.0147 (4)
O30.0305 (5)0.0277 (5)0.0376 (6)0.0014 (4)0.0205 (4)0.0182 (4)
O40.0218 (4)0.0159 (4)0.0178 (4)0.0018 (3)0.0072 (3)0.0040 (3)
C50.0408 (8)0.0200 (7)0.0276 (7)0.0065 (6)0.0072 (6)0.0031 (6)
C60.0174 (6)0.0191 (6)0.0147 (6)0.0076 (5)0.0012 (4)0.0034 (5)
O70.0212 (4)0.0209 (5)0.0201 (4)0.0022 (4)0.0103 (3)0.0048 (3)
O80.0280 (5)0.0219 (5)0.0193 (4)0.0088 (4)0.0060 (4)0.0069 (4)
C90.0156 (6)0.0220 (6)0.0139 (6)0.0063 (5)0.0025 (4)0.0023 (5)
C100.0146 (5)0.0156 (6)0.0142 (5)0.0042 (4)0.0012 (4)0.0024 (4)
C110.0167 (6)0.0179 (6)0.0149 (6)0.0062 (5)0.0007 (4)0.0028 (5)
C120.0215 (6)0.0169 (6)0.0222 (6)0.0051 (5)0.0012 (5)0.0045 (5)
C130.0210 (6)0.0197 (6)0.0257 (7)0.0013 (5)0.0036 (5)0.0007 (5)
C140.0178 (6)0.0273 (7)0.0164 (6)0.0054 (5)0.0049 (5)0.0002 (5)
Geometric parameters (Å, º) top
B1—O21.3443 (15)C6—C111.4971 (16)
B1—O31.3461 (16)O7—H81.03 (2)
B1—C91.5661 (17)C9—C141.3933 (17)
O2—H20.802 (19)C9—C101.3993 (16)
O3—H30.84 (2)C10—C111.4059 (16)
O4—C101.3813 (14)C11—C121.3931 (17)
O4—C51.4317 (15)C12—C131.3825 (18)
C5—H5A1.029 (17)C12—H120.938 (15)
C5—H5B0.942 (17)C13—C141.3799 (18)
C5—H5C0.968 (15)C13—H130.955 (15)
C6—O81.2607 (13)C14—H140.951 (14)
C6—O71.3044 (14)
O2—B1—O3119.64 (11)C14—C9—B1119.41 (10)
O2—B1—C9118.18 (11)C10—C9—B1122.49 (10)
O3—B1—C9122.16 (10)O4—C10—C9118.38 (10)
B1—O2—H2109.5 (13)O4—C10—C11120.37 (10)
B1—O3—H3104.3 (15)C9—C10—C11121.25 (11)
C10—O4—C5113.51 (10)C12—C11—C10118.37 (10)
O4—C5—H5A110.1 (9)C12—C11—C6116.96 (10)
O4—C5—H5B109.1 (10)C10—C11—C6124.66 (10)
H5A—C5—H5B107.3 (13)C13—C12—C11121.05 (11)
O4—C5—H5C108.6 (9)C13—C12—H12120.4 (9)
H5A—C5—H5C110.3 (13)C11—C12—H12118.5 (9)
H5B—C5—H5C111.4 (13)C14—C13—C12119.70 (12)
O8—C6—O7122.02 (10)C14—C13—H13121.3 (9)
O8—C6—C11119.10 (10)C12—C13—H13118.9 (9)
O7—C6—C11118.88 (10)C13—C14—C9121.55 (11)
C6—O7—H8114.0 (10)C13—C14—H14118.6 (8)
C14—C9—C10118.08 (11)C9—C14—H14119.8 (8)
O2—B1—C9—C1418.65 (16)O4—C10—C11—C60.00 (17)
O3—B1—C9—C14159.62 (11)C9—C10—C11—C6179.25 (10)
O2—B1—C9—C10162.83 (11)O8—C6—C11—C123.26 (16)
O3—B1—C9—C1018.89 (18)O7—C6—C11—C12176.22 (10)
C5—O4—C10—C993.35 (12)O8—C6—C11—C10177.57 (10)
C5—O4—C10—C1187.38 (13)O7—C6—C11—C102.95 (16)
C14—C9—C10—O4179.50 (10)C10—C11—C12—C130.30 (18)
B1—C9—C10—O40.96 (16)C6—C11—C12—C13179.52 (11)
C14—C9—C10—C110.24 (17)C11—C12—C13—C140.18 (19)
B1—C9—C10—C11178.30 (10)C12—C13—C14—C90.16 (19)
O4—C10—C11—C12179.16 (10)C10—C9—C14—C130.37 (17)
C9—C10—C11—C120.09 (17)B1—C9—C14—C13178.22 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O3i0.802 (19)1.96 (2)2.7572 (13)172.6 (18)
O3—H3···O40.84 (2)2.06 (2)2.7283 (12)136.8 (19)
O3—H3···O2ii0.84 (2)2.45 (2)3.0538 (14)130.2 (19)
O7—H8···O8iii1.03 (2)1.60 (2)2.6255 (11)177.0 (16)
Symmetry codes: (i) x+1, y+2, z+1; (ii) x1, y, z; (iii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC8H9BO5
Mr195.96
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)4.8451 (5), 7.7564 (7), 12.1064 (9)
α, β, γ (°)79.476 (7), 79.575 (7), 76.125 (8)
V3)429.75 (7)
Z2
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.32 × 0.20 × 0.14
Data collection
DiffractometerKuma KM4 CCD
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction 2005)
Tmin, Tmax0.95, 0.98
No. of measured, independent and
observed [I > 2σ(I)] reflections
12229, 2106, 1526
Rint0.018
(sin θ/λ)max1)0.674
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.101, 1.05
No. of reflections2106
No. of parameters163
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.35, 0.26

Computer programs: CrysAlis CCD (Oxford Diffraction (2005), CrysAlis RED (Oxford Diffraction (2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
B1—O21.3443 (15)C6—O81.2607 (13)
B1—O31.3461 (16)C6—O71.3044 (14)
B1—C91.5661 (17)
O2—B1—C9—C1418.65 (16)O8—C6—C11—C10177.57 (10)
C5—O4—C10—C993.35 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O3i0.802 (19)1.96 (2)2.7572 (13)172.6 (18)
O3—H3···O40.84 (2)2.06 (2)2.7283 (12)136.8 (19)
O3—H3···O2ii0.84 (2)2.45 (2)3.0538 (14)130.2 (19)
O7—H8···O8iii1.03 (2)1.60 (2)2.6255 (11)177.0 (16)
Symmetry codes: (i) x+1, y+2, z+1; (ii) x1, y, z; (iii) x, y+1, z.
 

Acknowledgements

The X-ray measurements were undertaken in the Crystallographic Unit of the Physical Chemistry Laboratory at the Chemistry Department of the University of Warsaw. This work was supported by the Warsaw University of Technology and by the Polish Ministry of Science and Higher Education (grant No. N N205 055633).

References

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