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(2E)-1-(Pyridin-2-yl)-3-(2,4,6-trimethoxyphenyl)prop-2-en-1-one
Hoong-Kun Fun,Suchada Chantrapromma,Thitipone Suwunwong
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811039110
Abstract: The title heteroaryl chalcone derivative, C17H17NO4, is a condensation product of 2-acetylpyridine and 2,4,6-trimethoxybenzaldehyde. The molecule is roughly planar, the dihedral angle between the pyridine and benzene rings being 5.51 (10)°. All the three methoxy groups are almost co-planar with the bound benzene ring [r.m.s. deviation of 0.0306 (2) ]. A weak C—H...O intramolecular interaction involving one of the ortho-methoxy groups generates an S(6) ring motif. In the crystal, the molecules are linked by weak C—H...O interactions into anti-parallel face-to-face pairs. Adjacent pairs are further connected into sheets parallel to the ab plane.
(E)-1-(4-Bromophenyl)-3-(2,4,6-trimethoxyphenyl)prop-2-en-1-oneThis paper is dedicated to the late Her Royal Highness Princess Galyani Vadhana Krom Luang Naradhiwas Rajanagarindra for her patronage of Science in Thailand.  [cached]
Suchada Chantrapromma,Thitipone Suwunwong,Chatchanok Karalai,Hoong-Kun Fun
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809010496
Abstract: The molecule of the title chalcone derivative, C18H17BrO4, is twisted, the dihedral angle between the 4-bromophenyl and 2,4,6-trimethoxyphenyl rings being 39.17 (6)°. The three methoxy groups are oriented in two different conformations whereby two methoxy groups are coplanar, whereas the third is twisted with respect to the attached benzene ring [C—O—C—C torsion angles of 2.84 (18), 2.80 (18) and 9.31 (18)°]. Weak intramolecular C—H...O interactions generate two S(5) and one S(6) ring motifs. In the crystal structure, molecules are linked into supramolecular sheets parallel to the bc plane by weak C—H...O interactions. These sheets are stacked along the a axis. The crystal structure is further stabilized by weak C—H...π interactions.
(E)-3-(6-Nitrobenzo[d][1,3]dioxol-5-yl)-1-(2,4,6-trimethoxyphenyl)prop-2-en-1-one
Hossein Loghmani-Khouzani,Noorsaadah Abdul Rahman,Ward T. Robinson,Marzieh Yaeghoobi
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809036435
Abstract: In the molecule of the title compound, C19H17NO8, the benzodioxole unit is oriented at a dihedral angle of 61.45 (6)° with respect to the methoxy-substituted phenyl ring. The nitro group is not co-planar to the benzene ring to which it is attached, making a dihedral angle of 31.86 (17)°. In the crystal structure, intermolecular C—H...O interactions link the molecules into chains through R22(8) ring motifs. The π...π contacts between the benzodioxole rings, [centroid–centroid distances = 3.7610 (9), 3.6613 (9) and 3.7975 (9) ] may further stabilize the structure.
(E)-1-[4-(Prop-2-yn-1-yloxy)phenyl]-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one  [cached]
S. Ranjith,A. Thirunarayanan,S. Raja,P. Rajakumar
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810031193
Abstract: The molecule of the title chalcone derivative, C21H20O5, consists of two substituted aromatic rings bridged by a prop-2-en-1-one group. The dihedral angle between the two benzene rings is 28.7 (7)°. In the crystal, molecules are linked into C(10) chains running along the a axis by intermolecular C—H...O hydrogen bonds, and the chains are cross-linked via C—H...π interactions.
A second polymorph of (2E)-1-(4-fluorophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one  [cached]
Jerry P. Jasinski,Ray J. Butcher,K. Veena,B. Narayana
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809028517
Abstract: The crystal structure of the title compound, C18H17FO4, reported here is a polymorph of the structure first reported by Patil et al. [Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. A (2007), 461, 123–130]. It is a chalcone analog and consists of substituted phenyl rings bonded at the opposite ends of a propenone group, the biologically active region. The dihedral angle between the mean planes of the aromatic rings within the 4-fluorophenyl and trimethoxyphenyl groups is 28.7 (1)° compared to 20.8 (6)° in the published structure. The angles between the mean plane of the prop-2-ene-1-one group and the mean plane of aromatic rings within the 4-fluorophenyl and trimethoxyphenyl groups are 30.3 (4) and 7.4 (7)°, respectively, in contast to 10.7 (3) and 12.36° for the polymorph. While the two 3-methoxy groups are in the plane of the trimethoxy-substituted ring, the 4-methoxy group is in a synclinical [ sc = 78.1 (2)°] or anticlinical [+ac = 104.0 (4)°] position, compared to a +sc [53.0 (4)°] or ac [ 132.4 (7)°] position. While no classical hydrogen bonds are present, weak intermolecular C—H...π-ring interactions are observed which contribute to the stability of the crystal packing. The two polymorphs crystallize in the same space group, P21/c, but have different cell parameters for the a, b and c axes and the β angle. A comparison of the molecular geometries of both polymorphs to a geometry optimized density functional theory (DFT) calculation at the B3-LYP/6–311+G(d,p) level for each structure provides additional support to these observations.
(E)-1-(2,4,6-Trimethoxyphenyl)pent-1-en-3-one  [cached]
Alain Collas,Frank Blockhuys
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810034641
Abstract: The title compound, C14H18O4, was obtained unintentionally as the major product of an attempted synthesis of (E,E)-2,5-bis[2-(2,4,6-trimethoxyphenyl)ethenyl]pyrazine. The crystal packing features layers based on two weak C—H...O hydrogen bonds involving the O atom of the carbonyl group and two Omethoxy...Cmethoxy interactions [3.109 (2) ]. The sheets are interconnected via methoxy–methoxy dimers and C—H...π interactions.
(1E,4E)-1,5-Bis(2,4,6-trimethoxyphenyl)penta-1,4-dien-3-one  [cached]
Pumsak Ruanwas,Suchada Chantrapromma,Hoong-Kun Fun
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536810049299
Abstract: There are two crystallographically independent molecules in the asymmetric unit of the title bischalcone derivative, C23H26O7. The molecules are unsymmetrical and almost planar: the dihedral angle between two benzene rings is 1.04 (7)° in one molecule and 2.31 (7)° in the other. The central penta-1,4-dien-3-one fragment makes dihedral angles of 7.61 (7) and 6.82 (7)° with the two adjacent benzene rings in one molecule, while the corresponding values are 7.85 (7) and 9.42 (6)° in the other. In both molecules, the three methoxy groups of the two 2,4,6-trimethoxyphenyl units are coplanar with the attached benzene rings [C—O—C—C- torsion angles of 1.5 (2), 7.2 (2) and 4.1 (2)° in one molecule and 0.7 (2), 5.5 (2) and 0.6 (2)° in the other]. The molecular conformations are stabilized by weak intramolecular C—H...O interactions generating two S(6) ring motifs. In the crystal, molecules are linked by weak intermolecular C—H...O interactions into zigzag chains parallel to the c axis. The crystal structure is further stabilized by C—H...π interactions and π–π interactions with centroid–centroid distances of 3.6433 (8) .
Tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP): Efficient Catalysts for the Cyanosilylation and Cyanocarbonation of Aldehydes and Ketones  [PDF]
Satoru Matsukawa,Izumi Sekine,Ayumi Iitsuka
Molecules , 2009, DOI: 10.3390/molecules14093353
Abstract: A variety of aldehydes and ketones were transformed to their corresponding cyanohydrin silyl ethers in good to excellent yields in the presence of 1-5 mol% of tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP). Cyanohydrin carbonates were also readily prepared using 5-10 mol% of TTMPP as an organocatalyst.
(E)-1-(2-Furyl)-3-(2,4,6-trimethoxyphenyl)prop-2-en-1-one  [cached]
Hoong-Kun Fun,Thitipone Suwunwong,Suchada Chantrapromma,Chatchanok Karalai
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810035762
Abstract: In the title heteroaryl chalcone derivative, C16H16O5, the dihedral angle between the furan and benzene rings is 14.45 (6)°. The three methoxy groups are almost coplanar with their attached benzene ring [C—C—O—C torsion angles = 2.07 (17), 5.04 (17) and 2.85 (16)°]. An intramolecular C—H...O hydrogen bond occurs. In the crystal, adjacent molecules are linked into X-shaped chains along the c axis by weak C—H...O(enone) interactions. These chains are stacked along the b axis. C...O [3.3308 (13)–3.4123 (14) ] short contacts are also observed.
(E)-1-(4-Methoxyphenyl)-3-(2,4,6-trimethoxyphenyl)prop-2-en-1-one
Yuepiao Cai,Zhankun Wang,Zhe Li,Meiling Zhang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811017788
Abstract: In the title compound, C19H20O5, the dihedral angle between the two aromatic rings is 18.23 (4)°. The crystal structure exhibits only weak C—H...π and C—H...O contacts between the molecules.
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