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In the crystal structure of the title compound, C20H14O2·1.5C3H7NO, one of the hydroxyl groups forms a hydrogen bond to the dimethyl­formamide (DMF) mol­ecule that lies on a general position and the other a hydrogen bond to the DMF mol­ecule that lies on a twofold rotation axis. The naphthyl residues are almost perpendicular to each other.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805030369/bt6743sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536805030369/bt6743Isup2.hkl
Contains datablock I

CCDC reference: 287483

Key indicators

  • Single-crystal X-ray study
  • T = 295 K
  • Mean [sigma](C-C) = 0.005 Å
  • Disorder in solvent or counterion
  • R factor = 0.099
  • wR factor = 0.254
  • Data-to-parameter ratio = 13.3

checkCIF/PLATON results

No syntax errors found



Alert level C RFACR01_ALERT_3_C The value of the weighted R factor is > 0.25 Weighted R factor given 0.254 PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings Differ .... ? PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............ 0.50 Ratio PLAT220_ALERT_2_C Large Non-Solvent C Ueq(max)/Ueq(min) ... 2.77 Ratio PLAT241_ALERT_2_C Check High Ueq as Compared to Neighbors for C19 PLAT244_ALERT_4_C Low 'Solvent' Ueq as Compared to Neighbors for N2 PLAT244_ALERT_4_C Low 'Solvent' Ueq as Compared to Neighbors for N1 PLAT302_ALERT_4_C Anion/Solvent Disorder ......................... 23.00 Perc. PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ... 5 PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 2 C3 H7 N O
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 11 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 4 ALERT type 4 Improvement, methodology, query or suggestion

Comment top

A number of solvates and clathrates of 1,1'-bi-2-naphthol have been structurally verified, as noted from a search of the Cambridge Structural Database (Version 5.26; Allen, 2002). The reagent itself exists in the racemic and optically active (+) and (-) forms. The title 1.5DMF solvate, (I), was originally reported in space group Cc (Hirano et al., 2003), but PLATON (Spek, 2003) suggests a centre of inversion in the crystal structure; this is confirmed in the present re-investigation of (I) (Fig. 1). In the higher-symmetric space group C2/c, one of the two DMF solvates is disordered over a twofold rotation axis.

The two aromatic systems of (I) enclose a dihedral angle of 88.4 (1)°. One of the hydroxy groups forms a hydrogen bond to the ordered DMF (which lies on a general position) and the other to the disordered DMF (which lies on a twofold rotation axis). Apart from these two hydrogen bonds (Table 1), there are no other important intermolecular interactions in the crystal. Racemic 1,1'-bi-2-naphthol crystallizes in the non-centrosymmetric space group Iba2 (Gridunova et al., 1982; Mori et al., 1993; Toda et al., 1997, Nieger, 1999) and also has the two naphthol residues in an almost perpendicular orientation.

Experimental top

Racemic 1,1'-bi-2-naphthol (0.29 g, 1 mmol) was dissolved in a mixed solvent system of water (5 ml) and dimethylformamide (5 ml). This solution was added to an ethanol solution (10 ml) of 2-aminopyrimidine (0.19 g, 2 mmol). Evaporation of the solvent over several weeks gave colourless block-shaped crystals of (I). The diffraction measurements represent the best of six sets of measurements; the crystals were not strongly diffracting in any of the attempts.

Refinement top

One DMF molecule is disordered over a twofold rotation axis. A number of restraints were imposed on this molecule, as follows: C24—O4 = 1.25 (1), C24—N2 = 1.35 (1), N2—C25 = N2—C26 = 1.45 (1), O4···C25 = 2.71 (1), C24···C25 = C24···C26 = 2.43 (2) and C25···C26 = 2.51 (2) Å. The displacement parameters of these atoms were restrained to an approximate isotropic behaviour; furthermore, these atoms were restrained to lie in a common plane. H atoms were generated geometrically (O—H = 0.82, C—Haromatic = 0.93 and C—Hmethyl = 0.96 Å), and were included in the refinement in the riding-model approximation, with Uiso(H) = 1.2Ueq(C,O), or 1.5Ueq(C) for methyl groups.

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Figures top
[Figure 1] Fig. 1. A plot of (I), with displacement ellipsoids drawn at the 30% probability level. H atoms are shown as spheres of arbitrary radii.
Racemic 1,1'-bi-2-naphthol dimethylformamide sesquisolvate top
Crystal data top
C20H14O2·1.5C3H7NOF(000) = 1680
Mr = 395.96Dx = 1.222 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2122 reflections
a = 14.250 (1) Åθ = 2.4–20.7°
b = 10.806 (1) ŵ = 0.08 mm1
c = 28.126 (2) ÅT = 295 K
β = 96.374 (1)°Block, colourless
V = 4304.1 (6) Å30.42 × 0.18 × 0.15 mm
Z = 8
Data collection top
Bruker APEX CCD area-detector
diffractometer
3000 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.029
Graphite monochromatorθmax = 25.0°, θmin = 2.4°
ω and ϕ scansh = 1616
11051 measured reflectionsk = 128
3790 independent reflectionsl = 3333
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)] = 0.099Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.254H-atom parameters constrained
S = 1.18 w = 1/[σ2(Fo2) + (0.1082P)2 + 6.5323P]
where P = (Fo2 + 2Fc2)/3
3790 reflections(Δ/σ)max = 0.001
286 parametersΔρmax = 0.46 e Å3
40 restraintsΔρmin = 0.36 e Å3
Crystal data top
C20H14O2·1.5C3H7NOV = 4304.1 (6) Å3
Mr = 395.96Z = 8
Monoclinic, C2/cMo Kα radiation
a = 14.250 (1) ŵ = 0.08 mm1
b = 10.806 (1) ÅT = 295 K
c = 28.126 (2) Å0.42 × 0.18 × 0.15 mm
β = 96.374 (1)°
Data collection top
Bruker APEX CCD area-detector
diffractometer
3000 reflections with I > 2σ(I)
11051 measured reflectionsRint = 0.029
3790 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.09940 restraints
wR(F2) = 0.254H-atom parameters constrained
S = 1.18Δρmax = 0.46 e Å3
3790 reflectionsΔρmin = 0.36 e Å3
286 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.5386 (2)0.6903 (3)0.5587 (1)0.070 (1)
O20.4730 (2)0.7629 (2)0.6736 (1)0.058 (1)
O30.5401 (3)0.8198 (5)0.4778 (1)0.118 (2)
O40.50000.9273 (4)0.75000.106 (2)
N10.6382 (3)0.9121 (4)0.4317 (1)0.065 (1)
N20.50001.1334 (5)0.75000.082 (2)
C10.4445 (2)0.5759 (3)0.6056 (1)0.036 (1)
C20.4549 (3)0.6346 (4)0.5632 (1)0.049 (1)
C30.3801 (3)0.6374 (4)0.5258 (1)0.063 (1)
C40.2973 (3)0.5809 (4)0.5310 (1)0.059 (1)
C50.2825 (2)0.5184 (3)0.5734 (1)0.046 (1)
C60.3570 (2)0.5168 (3)0.6114 (1)0.037 (1)
C70.3406 (3)0.4560 (4)0.6539 (1)0.049 (1)
C80.2563 (3)0.3997 (4)0.6586 (2)0.069 (1)
C90.1839 (3)0.4008 (4)0.6211 (2)0.068 (1)
C100.1968 (3)0.4591 (4)0.5798 (2)0.059 (1)
C110.5235 (2)0.5726 (3)0.6449 (1)0.036 (1)
C120.5351 (2)0.6656 (3)0.6780 (1)0.040 (1)
C130.6088 (3)0.6625 (4)0.7159 (1)0.053 (1)
C140.6715 (3)0.5681 (4)0.7196 (1)0.055 (1)
C150.6643 (3)0.4705 (4)0.6864 (1)0.050 (1)
C160.5887 (2)0.4722 (3)0.6487 (1)0.042 (1)
C170.5815 (3)0.3738 (4)0.6154 (2)0.057 (1)
C180.6466 (4)0.2800 (5)0.6193 (2)0.087 (2)
C190.7197 (4)0.2781 (6)0.6557 (2)0.099 (2)
C200.7289 (3)0.3714 (5)0.6883 (2)0.079 (2)
C210.6120 (5)0.8212 (6)0.4580 (2)0.100 (2)
C220.5824 (5)1.0214 (7)0.4251 (3)0.126 (3)
C230.7238 (6)0.9074 (8)0.4094 (3)0.147 (3)
C240.4962 (5)1.0288 (7)0.7700 (3)0.094 (3)0.50
C250.510 (1)1.125 (1)0.6967 (3)0.180 (7)0.50
C260.4978 (6)1.2613 (8)0.7627 (5)0.129 (6)0.50
H10.53630.72390.53250.084*
H20.48540.81080.69610.069*
H30.38790.67840.49750.076*
H40.24880.58350.50600.071*
H70.38820.45410.67930.059*
H80.24720.36030.68720.083*
H90.12690.36160.62440.081*
H100.14780.46020.55500.071*
H130.61430.72570.73850.063*
H140.72020.56780.74450.066*
H170.53230.37260.59080.069*
H180.64130.21640.59690.104*
H190.76280.21310.65800.119*
H200.77900.36980.71250.095*
H210.65130.75240.46190.120*
H22a0.53201.00810.40000.189*
H22b0.62111.08880.41660.189*
H22c0.55651.04100.45430.189*
H23a0.76290.84150.42320.220*
H23b0.75680.98460.41430.220*
H23c0.70900.89310.37570.220*
H240.48991.02820.80260.113*0.50
H25a0.55701.06450.69150.269*0.50
H25b0.52731.20380.68520.269*0.50
H25c0.45021.09980.67990.269*0.50
H26a0.44201.29900.74670.194*0.50
H26b0.55271.30210.75340.194*0.50
H26c0.49711.26870.79670.194*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.061 (2)0.097 (2)0.051 (2)0.031 (2)0.0004 (1)0.022 (2)
O20.066 (2)0.046 (2)0.058 (2)0.010 (1)0.009 (1)0.013 (1)
O30.111 (3)0.169 (5)0.072 (2)0.066 (3)0.009 (2)0.033 (3)
O40.173 (5)0.043 (3)0.093 (4)0.0000.022 (3)0.000
N10.066 (2)0.069 (3)0.061 (2)0.005 (2)0.015 (2)0.010 (2)
N20.106 (4)0.041 (3)0.100 (4)0.0000.021 (3)0.000
C10.039 (2)0.031 (2)0.037 (2)0.001 (1)0.000 (1)0.003 (1)
C20.047 (2)0.053 (2)0.044 (2)0.008 (2)0.003 (2)0.003 (2)
C30.068 (3)0.083 (3)0.036 (2)0.007 (2)0.008 (2)0.009 (2)
C40.048 (2)0.075 (3)0.048 (2)0.004 (2)0.016 (2)0.002 (2)
C50.040 (2)0.046 (2)0.049 (2)0.002 (2)0.004 (2)0.010 (2)
C60.037 (2)0.030 (2)0.044 (2)0.002 (1)0.003 (2)0.006 (1)
C70.043 (2)0.048 (2)0.055 (2)0.009 (2)0.002 (2)0.005 (2)
C80.071 (3)0.066 (3)0.073 (3)0.021 (2)0.017 (2)0.006 (2)
C90.043 (2)0.072 (3)0.089 (3)0.021 (2)0.011 (2)0.007 (3)
C100.038 (2)0.062 (3)0.074 (3)0.008 (2)0.008 (2)0.018 (2)
C110.035 (2)0.038 (2)0.034 (2)0.005 (1)0.004 (1)0.003 (1)
C120.038 (2)0.037 (2)0.045 (2)0.004 (2)0.002 (2)0.006 (2)
C130.052 (2)0.059 (3)0.044 (2)0.013 (2)0.005 (2)0.004 (2)
C140.041 (2)0.074 (3)0.045 (2)0.001 (2)0.012 (2)0.013 (2)
C150.041 (2)0.059 (2)0.048 (2)0.007 (2)0.001 (2)0.015 (2)
C160.040 (2)0.041 (2)0.044 (2)0.002 (2)0.006 (2)0.008 (2)
C170.062 (3)0.051 (2)0.059 (2)0.009 (2)0.004 (2)0.003 (2)
C180.107 (4)0.065 (3)0.087 (4)0.035 (3)0.011 (3)0.006 (3)
C190.106 (4)0.085 (4)0.106 (5)0.060 (3)0.006 (4)0.010 (3)
C200.064 (3)0.097 (4)0.072 (3)0.031 (3)0.004 (2)0.020 (3)
C210.127 (5)0.091 (4)0.077 (4)0.021 (4)0.005 (4)0.005 (3)
C220.112 (5)0.141 (6)0.121 (6)0.032 (5)0.002 (4)0.040 (5)
C230.127 (6)0.166 (8)0.161 (7)0.002 (5)0.079 (6)0.026 (6)
C240.142 (8)0.079 (6)0.060 (5)0.005 (6)0.008 (6)0.017 (5)
C250.22 (1)0.16 (1)0.16 (1)0.010 (9)0.037 (9)0.011 (9)
C260.181 (9)0.088 (7)0.12 (1)0.005 (8)0.032 (8)0.003 (6)
Geometric parameters (Å, º) top
O1—C21.355 (4)C18—C191.378 (8)
O2—C121.371 (4)C19—C201.360 (8)
O3—C211.220 (7)O1—H10.82
O4—C241.236 (7)O2—H20.82
N1—C211.308 (7)C3—H30.93
N1—C221.424 (7)C4—H40.93
N1—C231.434 (7)C7—H70.93
N2—C241.267 (7)C8—H80.93
N2—C261.429 (8)C9—H90.93
N2—C251.522 (9)C10—H100.93
C1—C21.374 (5)C13—H130.93
C1—C61.426 (5)C14—H140.93
C1—C111.487 (4)C17—H170.93
C2—C31.412 (5)C18—H180.93
C3—C41.351 (6)C19—H190.93
C4—C51.405 (6)C20—H200.93
C5—C101.409 (5)C21—H210.93
C5—C61.420 (5)C22—H22a0.96
C6—C71.407 (5)C22—H22b0.96
C7—C81.367 (5)C22—H22c0.96
C8—C91.392 (7)C23—H23a0.96
C9—C101.352 (6)C23—H23b0.96
C11—C121.368 (5)C23—H23c0.96
C11—C161.424 (5)C24—H240.93
C12—C131.412 (5)C25—H25a0.96
C13—C141.352 (6)C25—H25b0.96
C14—C151.405 (6)C25—H25c0.96
C15—C201.410 (6)C26—H26a0.96
C15—C161.425 (5)C26—H26b0.96
C16—C171.413 (5)C26—H26c0.96
C17—C181.370 (6)
C21—N1—C22120.4 (5)C4—C3—H3119.8
C21—N1—C23122.0 (6)C2—C3—H3119.8
C22—N1—C23117.5 (6)C3—C4—H4119.2
C24—N2—C26138.5 (7)C5—C4—H4119.2
C24—N2—C25113.2 (7)C8—C7—H7119.3
C26—N2—C25108.3 (8)C6—C7—H7119.3
C2—C1—C6119.0 (3)C7—C8—H8119.7
C2—C1—C11120.6 (3)C9—C8—H8119.7
C6—C1—C11120.4 (3)C10—C9—H9120.1
O1—C2—C1117.9 (3)C8—C9—H9120.1
O1—C2—C3121.3 (3)C9—C10—H10119.2
C1—C2—C3120.8 (3)C5—C10—H10119.2
C4—C3—C2120.4 (4)C14—C13—H13119.8
C10—C5—C4122.8 (3)C12—C13—H13119.8
C10—C5—C6118.9 (4)C13—C14—H14119.4
C4—C5—C6118.3 (3)C15—C14—H14119.4
C7—C6—C5117.7 (3)C18—C17—H17119.8
C7—C6—C1122.3 (3)C16—C17—H17119.8
C5—C6—C1119.9 (3)C19—C18—H18119.3
C8—C7—C6121.4 (4)C17—C18—H18119.3
C3—C4—C5121.6 (3)C20—C19—H19120.1
C7—C8—C9120.5 (4)C18—C19—H19120.1
C10—C9—C8119.7 (4)C19—C20—H20119.2
C9—C10—C5121.7 (4)C15—C20—H20119.2
C12—C11—C16118.7 (3)O3—C21—H21117.5
C12—C11—C1120.8 (3)N1—C21—H21117.5
C16—C11—C1120.5 (3)N1—C22—H22a109.5
C11—C12—O2118.4 (3)N1—C22—H22b109.5
C11—C12—C13121.3 (3)H22a—C22—H22b109.5
O2—C12—C13120.3 (3)N1—C22—H22c109.5
C14—C13—C12120.4 (4)H22a—C22—H22c109.5
C13—C14—C15121.1 (3)H22b—C22—H22c109.5
C14—C15—C20123.1 (4)N1—C23—H23a109.5
C14—C15—C16118.6 (3)N1—C23—H23b109.5
C20—C15—C16118.3 (4)H23a—C23—H23b109.5
C17—C16—C15118.4 (3)N1—C23—H23c109.5
C17—C16—C11121.7 (3)H23a—C23—H23c109.5
C15—C16—C11119.9 (3)H23b—C23—H23c109.5
C18—C17—C16120.4 (4)O4—C24—H24117.2
C19—C18—C17121.3 (5)N2—C24—H24117.2
C20—C19—C18119.9 (5)N2—C26—H26a109.5
C19—C20—C15121.6 (5)N2—C26—H26b109.5
O3—C21—N1125.0 (7)H26a—C26—H26b109.5
O4—C24—N2125.7 (7)N2—C26—H26c109.5
C2—O1—H1109.5H26a—C26—H26c109.5
C12—O2—H2109.5H26b—C26—H26c109.5
C6—C1—C2—O1179.8 (3)C16—C11—C12—O2179.0 (3)
C11—C1—C2—O10.9 (5)C1—C11—C12—O21.1 (5)
C6—C1—C2—C30.4 (6)C16—C11—C12—C131.1 (5)
C11—C1—C2—C3179.7 (4)C1—C11—C12—C13178.8 (3)
O1—C2—C3—C4179.8 (4)C11—C12—C13—C141.7 (5)
C1—C2—C3—C40.8 (7)O2—C12—C13—C14178.4 (3)
C2—C3—C4—C50.2 (7)C12—C13—C14—C150.9 (6)
C3—C4—C5—C10179.7 (4)C13—C14—C15—C20178.8 (4)
C3—C4—C5—C60.8 (6)C13—C14—C15—C160.5 (6)
C10—C5—C6—C70.2 (5)C14—C15—C16—C17179.9 (4)
C4—C5—C6—C7178.7 (3)C20—C15—C16—C170.8 (5)
C10—C5—C6—C1179.8 (3)C14—C15—C16—C111.0 (5)
C4—C5—C6—C11.2 (5)C20—C15—C16—C11178.3 (4)
C2—C1—C6—C7179.3 (3)C12—C11—C16—C17179.3 (3)
C11—C1—C6—C71.3 (5)C1—C11—C16—C170.8 (5)
C2—C1—C6—C50.6 (5)C12—C11—C16—C150.3 (5)
C11—C1—C6—C5178.7 (3)C1—C11—C16—C15179.8 (3)
C5—C6—C7—C80.3 (6)C15—C16—C17—C180.7 (6)
C1—C6—C7—C8179.8 (4)C11—C16—C17—C18178.3 (4)
C6—C7—C8—C90.2 (7)C16—C17—C18—C190.7 (8)
C7—C8—C9—C100.6 (7)C17—C18—C19—C200.8 (9)
C8—C9—C10—C50.7 (7)C18—C19—C20—C150.9 (9)
C4—C5—C10—C9179.2 (4)C14—C15—C20—C19179.8 (5)
C6—C5—C10—C90.2 (6)C16—C15—C20—C190.9 (7)
C2—C1—C11—C1288.1 (4)C22—N1—C21—O31.4 (9)
C6—C1—C11—C1292.6 (4)C23—N1—C21—O3179.9 (6)
C2—C1—C11—C1692.0 (4)C26—N2—C24—O4179.8 (5)
C6—C1—C11—C1687.3 (4)C25—N2—C24—O40.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O30.821.862.674 (5)172
O2—H2···O40.821.962.781 (4)174

Experimental details

Crystal data
Chemical formulaC20H14O2·1.5C3H7NO
Mr395.96
Crystal system, space groupMonoclinic, C2/c
Temperature (K)295
a, b, c (Å)14.250 (1), 10.806 (1), 28.126 (2)
β (°) 96.374 (1)
V3)4304.1 (6)
Z8
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.42 × 0.18 × 0.15
Data collection
DiffractometerBruker APEX CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
11051, 3790, 3000
Rint0.029
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.099, 0.254, 1.18
No. of reflections3790
No. of parameters286
No. of restraints40
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.46, 0.36

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEPII (Johnson, 1976), SHELXL97.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O30.821.862.674 (5)172
O2—H2···O40.821.962.781 (4)174
 

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