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Crystal structure of 3-(2,2-di-bromo-acet-yl)-4-hy-droxy-2H-chromen-2-one.

Brahmia A, Ghouili A, Ben Hassen R - Acta Crystallogr E Crystallogr Commun (2015)

Bottom Line: The title compound, C11H6Br2O4, is a new coumarin derivative obtained from the reaction of 3-acetyl-4-hy-droxy-2H-chromen-2-one with bromine in acetic acid.The hy-droxyl group in involved in an intra-molecular O-H⋯O hydrogen bond.In the crystal, π-π inter-actions between the rings of the bicycle [inter-centroid distances = 3.498 (2) and 3.539 (2) Å] pack mol-ecules into stacks along the b axis, and weak inter-molecular C-H⋯O hydrogen bonds further link these stacks into layers parallel to the ab plane.

View Article: PubMed Central - HTML - PubMed

Affiliation: Unité de Chimie des Matériaux et de l'Environnement UR11ES25, ISSBAT, Université de Tunis-El Manar, 9, Avenue Dr. Zoheir SAFI, 1006 Tunis, Tunisia.

ABSTRACT
The title compound, C11H6Br2O4, is a new coumarin derivative obtained from the reaction of 3-acetyl-4-hy-droxy-2H-chromen-2-one with bromine in acetic acid. The hy-droxyl group in involved in an intra-molecular O-H⋯O hydrogen bond. In the crystal, π-π inter-actions between the rings of the bicycle [inter-centroid distances = 3.498 (2) and 3.539 (2) Å] pack mol-ecules into stacks along the b axis, and weak inter-molecular C-H⋯O hydrogen bonds further link these stacks into layers parallel to the ab plane.

No MeSH data available.


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The mol­ecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Intra­molecular hydrogen bonds are shown as dashed lines.
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fig1: The mol­ecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Intra­molecular hydrogen bonds are shown as dashed lines.

Mentions: In the title compound (Fig. 1 ▸), the hy­droxy group is involved in formation of an intra­molecular O—H⋯O hydrogen bond (Table 1 ▸). In fact, the O3—H5 distance of 0.94 (7) Å has decreased from 1.02 (3) Å, observed in the starting reagent 3-acetyl-4-hy­droxy-2H-chromen-2-one (Lyssenko & Anti­pin, 2001 ▸). The H5⋯O4 distance of 1.65 (7) Å is elongated compared with its value in the parent compound [1.45 (3) Å], and the O3—H5⋯O4 angle of 147 (6)° is significantly smaller than that found for the starting reagent [161 (2)°]. This trend has already been observed in the fluorinated compound 2-di­fluoro­acetyl-1,3-cyclo­hexa­dione (Grieco et al., 2011 ▸), in which the O3—H5 and H5⋯O4 distances are even more affected (0.908 and 1.658 Å respectively). These observations can be easily understood from the point of view of the strong attractive effect of the halogen atoms due to their high electronegativities. All these geometrical parameters are in good agreement with the significant attractor effect of the halogen atoms, which affects the lone pairs of the oxygen atom O4, leading to a decrease of the attractor effect of O4 in the H5⋯O4 hydrogen bond and, consequently, an increase in the H5⋯O4 distance.


Crystal structure of 3-(2,2-di-bromo-acet-yl)-4-hy-droxy-2H-chromen-2-one.

Brahmia A, Ghouili A, Ben Hassen R - Acta Crystallogr E Crystallogr Commun (2015)

The mol­ecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Intra­molecular hydrogen bonds are shown as dashed lines.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4384588&req=5

fig1: The mol­ecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Intra­molecular hydrogen bonds are shown as dashed lines.
Mentions: In the title compound (Fig. 1 ▸), the hy­droxy group is involved in formation of an intra­molecular O—H⋯O hydrogen bond (Table 1 ▸). In fact, the O3—H5 distance of 0.94 (7) Å has decreased from 1.02 (3) Å, observed in the starting reagent 3-acetyl-4-hy­droxy-2H-chromen-2-one (Lyssenko & Anti­pin, 2001 ▸). The H5⋯O4 distance of 1.65 (7) Å is elongated compared with its value in the parent compound [1.45 (3) Å], and the O3—H5⋯O4 angle of 147 (6)° is significantly smaller than that found for the starting reagent [161 (2)°]. This trend has already been observed in the fluorinated compound 2-di­fluoro­acetyl-1,3-cyclo­hexa­dione (Grieco et al., 2011 ▸), in which the O3—H5 and H5⋯O4 distances are even more affected (0.908 and 1.658 Å respectively). These observations can be easily understood from the point of view of the strong attractive effect of the halogen atoms due to their high electronegativities. All these geometrical parameters are in good agreement with the significant attractor effect of the halogen atoms, which affects the lone pairs of the oxygen atom O4, leading to a decrease of the attractor effect of O4 in the H5⋯O4 hydrogen bond and, consequently, an increase in the H5⋯O4 distance.

Bottom Line: The title compound, C11H6Br2O4, is a new coumarin derivative obtained from the reaction of 3-acetyl-4-hy-droxy-2H-chromen-2-one with bromine in acetic acid.The hy-droxyl group in involved in an intra-molecular O-H⋯O hydrogen bond.In the crystal, π-π inter-actions between the rings of the bicycle [inter-centroid distances = 3.498 (2) and 3.539 (2) Å] pack mol-ecules into stacks along the b axis, and weak inter-molecular C-H⋯O hydrogen bonds further link these stacks into layers parallel to the ab plane.

View Article: PubMed Central - HTML - PubMed

Affiliation: Unité de Chimie des Matériaux et de l'Environnement UR11ES25, ISSBAT, Université de Tunis-El Manar, 9, Avenue Dr. Zoheir SAFI, 1006 Tunis, Tunisia.

ABSTRACT
The title compound, C11H6Br2O4, is a new coumarin derivative obtained from the reaction of 3-acetyl-4-hy-droxy-2H-chromen-2-one with bromine in acetic acid. The hy-droxyl group in involved in an intra-molecular O-H⋯O hydrogen bond. In the crystal, π-π inter-actions between the rings of the bicycle [inter-centroid distances = 3.498 (2) and 3.539 (2) Å] pack mol-ecules into stacks along the b axis, and weak inter-molecular C-H⋯O hydrogen bonds further link these stacks into layers parallel to the ab plane.

No MeSH data available.


Related in: MedlinePlus