837 research outputs found
The structure of triphenylgermanium hydroxide
C18H~6GeO, Mr = 320.9, triclinic, Pi, a =
15.408 (6), b = 19.974 (7), c = 23.264 (11) A, a =
107.78 (4), 13 = 1.03.54 (4), y= 101.51 (3) °, V =
6338 (5)/~3, Z = 16, Dx = 1.34 g cm -3, a(Mo Ka) =
0.71073A, /z = 19.1cm-1, F(000)=2624, T=
293 K, R = 0.055 for 6846 observed reflections. The
eight independent molecules in the asymmetric unit
form two independent O--H...O hydrogen-bonded
tetramers with the O atoms in a flattened tetrahedral
arrangement [hydrogen-bond distances in the range
2.609 (11) to 2.657 (11)A]. The Ge atoms are tetrahedrally
coordinated with mean Gc O 1.791 (7) and
Gc C 1.931 (8) A
Regio- and stereospecific assembly of dispiro[indoline-3,3′-pyrrolizine-1′,5′′-thiazolidines] from simple precursors using a one-pot procedure : synthesis, spectroscopic and structural characterization, and a proposed mechanism of formation
The authors thank 'Centro de Instrumentación Científico-Técnica of Universidad de Jaén' for data collection. The authors thank COLCIENCIAS, Universidad del Valle, the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) and the Universidad de Jaén for financial support. JQ thanks the AUIP for a scholarship granted for a stay at the Universidad de Jaén.The synthesis and characterization of three new dispiro[indoline-3,3′-pyrrolizine-1′,5′′-thiazolidine] compounds are reported, together with the crystal structures of two of them. (3RS,1′SR,2′SR,7a′SR)-2′-(4-Chlorophenyl)-1-hexyl-2′′-sulfanylidene-5′,6′,7′,7a′-tetrahydro-2′H-dispiro[indoline-3,3′-pyrrolizine-1′,5′′-thiazolidine]-2,4′′-dione, C28H30ClN3O2S2, (I), (3RS,1′SR,2′SR,7a′SR)-2′-(4-chlorophenyl)-1-benzyl-5-methyl-2′′-sulfanylidene-5′,6′,7′,7a′-tetrahydro-2′H-dispiro[indoline-3,3′-pyrrolizine-1′,5′′-thiazolidine]-2,4′′-dione, C30H26ClN3O2S2, (II), and (3RS,1′SR,2′SR,7a′SR)-2′-(4-chlorophenyl)-5-fluoro-2′′-sulfanylidene-5′,6′,7′,7a′-tetrahydro-2′H-dispiro[indoline-3,3′-pyrrolizine-1′,5′′-thiazolidine]-2,4′′-dione, C22H17ClFN3O2S2, (III), were each isolated as a single regioisomer using a one-pot reaction involving L -proline, a substituted isatin and (Z)-5-(4-chlorobenzylidene)-2-sulfanylidenethiazolidin-4-one [5-(4-chlorobenzylidene)rhodanine]. The compositions of (I)–(III) were established by elemental analysis, complemented by high-resolution mass spectrometry in the case of (I); their constitutions, including the definition of the regiochemistry, were established using NMR spectroscopy, and the relative configurations at the four stereogenic centres were established using single-crystal X-ray structure analysis. A possible reaction mechanism for the formation of (I)–(III) is proposed, based on the detailed stereochemistry. The molecules of (I) are linked into simple chains by a single N—H⋯N hydrogen bond, those of (II) are linked into a chain of rings by a combination of N—H⋯O and C—H⋯S=C hydrogen bonds, and those of (III) are linked into sheets by a combination of N—H⋯N and N—H⋯S=C hydrogen bonds.Publisher PDFPeer reviewe
O-H...π(arene) intermolecular hydrogen bonding in the structure of 1,1,2-triphenylethanol
The 1,1,2-triphenylethanol molecule, Ph2(PhCH2)COH
(I), forms centrosymmetric dimers in the solid state.
The shortest O-..O separation, 5.837 (3)A,, is too long
for any O--H..-O hydrogen-bond formation. Instead,
there are O--H~..π(arene) interactions between the
hydroxyl group of one molecule and a phenyl group of
a centrosymmetrically related molecule. The O...C and
H-..C distances between the hydroxyl group and the
closest phenyl-ring C atom are 3.525 (4) and 2.73 (4)~,,
respectively. These intermolecular contacts are the only
driving force towards dimer formation in the solid state
(1'-Benzoylferrocenyl)diphenylmethanol; a Centrosymmetric R⁴₄(16) Dimer Generated by C-H...O Hydrogen Bonding
In (1'-benzoylferrocenyl)diphenylmethanol, [(PhCOC₅H₄)Fe(C₅H₄)]CPh₂OH, (C₃₀H₂₄FeO₂), there is an intramolecular O-H...O hydrogen bond with O...O 2.891 (2) Å: the ferrocenyl unit adopts an eclipsed conformation and the molecules are linked into centrosymmetric dimers by C-H...O hydrogen bonds with C...O 3.357 (3) Å, to generate a cyclic R⁴₄(16) motif
Structures of 1-ferrocenyl-1-phenylethanol, ferrocenyl(diphenyl)methanol and ferrocene-1,1'-diylbis(diphenylmethanol)
Racemic 1-ferrocenyl- 1-phenylethanol, [(CsHs)Fe-
(CsHa)]CPhMeOH (I), crystallizes as discrete molecules
which are not involved in hydrogen bondinog; the shortest
intermolecular O-..O contact is 3.768(3) A and the hydroxyl
H atom is orientated towards the unsubstituted cyclopentadienyl ring. Ferrocenyl(diphenyl)methanol,
[(CsHs)Fe(CsHa)]CPh2OH (II) is hydrogen bonded to
form centrosynunetric dimers with O...O 2.816(1) and
H...O 2.52 ]k. Ferrocene-l,l~-diylbis(diphenylmeth -
anol), Fe[(CsHa)C(Ph)2COH]2 (III) crystallizes as a
dimeric aggregate with the Fe atoms on twofold crystallographic symmetry axes and the four O atoms defining a folded trapezium with O...O 2.762(2), 2.714(2)
and 2.865(2) A,. The four hydroxyl groups are disordered
equally over two orientations such that there are two halfoccupancy H-atom sites between each hydrogen-bonded
oxygen pair
Hydrogen-bonding patterns in ferrocene derivatives: structures of 1,1'-diphenyl-1,1'-(1,1'-ferrocenediyl)diethanol and 1,1'-(1,1'-ferrocenediyl)diethanol
Racemic 1, l'-diphenyl- 1,1'-( 1, l'-ferrocenediyl)diethanol,
[Fe{(CsH4)C(Ph)MeOH}2] (I), crystallizes as hydrogen-
bonded dimeric aggregates with the Fe atoms on
twofold crystallographic axes and the four O atoms defining
a folded trapezium with O...O distances of 2.784 (2)
(x2), 2.877(3) and 2.795 (4)A. The four hydroxyl H
atoms are disordered equally over two orientations such
that there are two half-occupancy H-atom sites between
each hydrogen-bonded O-atom pair. Racemic 1,1'-(1, l'-
ferrocenediyl)diethanol, [Fe{(CsH4)C(H)MeOH}2] (II),crystallizes as hydrogen-bonded centrosymmetric dimers,
with O...O distances of 2.778 (2) and 2.764 (2) A and ordered hydroxyl H atoms. In (I), the dimers are formed
from either two RR or two SS molecules, while in (II) the
dimers each contain one RR and one SS molecule
Synthesis of N-substituted 3-(2-aryl-2-oxoethyl)-3-hydroxyindolin-2-ones and their conversion to N-substituted (E)-3-(2-aryl-2-oxoethylidene)indolin-2-ones : synthetic sequence, spectroscopic characterization and structures of four 3-hydroxy compounds and five oxoethylidene products
The authors thank `Centro de Instrumentación Científico-Técnica' of Universidad de Jaén and its staff for data collection. They also thank Universidad del Valle, Universidad Pedagógica y Tecnológica de Colombia (project SGI-2829), Universidad de Jaén and the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain), for financial support. DB also thanks the Asociación Universitaria Iberoamericana de Postgrado for financial support.An operationally simple and time-efficient approach has been developed for the synthesis of racemic N-substituted 3-(2-aryl-2-oxoethyl)-3-hydroxyindolin-2-ones by a piperidine-catalysed aldol reaction between aryl methyl ketones and N-alkylisatins. These aldol products were used successfully as strategic intermediates for the preparation of N-substituted (E)-3-(2-hetaryl-2-oxoethylidene)indolin-2-ones by a stereoselective dehydration reaction under acidic conditions. The products have all been fully characterized by 1H and 13C NMR spectroscopy, by mass spectrometry and, for a representative selection, by crystal structure analysis. In each of (RS)-1-benzyl-3-hydroxy-3-[2-(4-methoxyphenyl)-2-oxoethyl]indolin-2-one, C24H21NO4, (Ic), and (RS)-1-benzyl-3-{2-[4-(dimethylamino)phenyl]-2-oxoethyl}-3-hydroxyindolin-2-one, C25H24N2O3, (Id), inversion-related pairs of molecules are linked by O—H⋯O hydrogen bonds to form R22(10) rings, which are further linked into chains of rings by a combination of C—H⋯O and C—H⋯π(arene) hydrogen bonds in (Ic) and by C—H⋯π(arene) hydrogen bonds in (Id). The molecules of (RS)-1-benzyl-3-hydroxy-3-[2-oxo-2-(pyridin-4-yl)ethyl]indolin-2-one, C22H18N2O3, (Ie), are linked into a three-dimensional framework structure by a combination of O—H⋯N, C—H⋯O and C—H⋯π(arene) hydrogen bonds. (RS)-3-[2-(Benzo[d][1,3]dioxol-5-yl)-2-oxoethyl]-1-benzyl-3-hydroxyindolin-2-one, C24H19NO5, (If), crystallizes with Z′ = 2 in the space group P and the molecules are linked into complex sheets by a combination of O—H⋯O, C—H⋯O and C—H⋯π(arene) hydrogen bonds. In each of (E)-1-benzyl-3-[2-(4-fluorophenyl)-2-oxoethylidene]indolin-2-one, C23H16FNO2, (IIa), and (E)-1-benzyl-3-[2-oxo-2-(thiophen-2-yl)ethylidene]indolin-2-one, C21H15NO2S, (IIg), the molecules are linked into simple chains by a single C—H⋯O hydrogen bond, while those of (E)-1-benzyl-3-[2-oxo-2-(pyridin-4-yl)ethylidene]indolin-2-one, C22H16N2O2, (IIe), are linked by three C—H⋯O hydrogen bonds to form sheets which are further linked into a three-dimensional structure by C—H⋯π(arene) hydrogen bonds. There are no hydrogen bonds in the structures of either (E)-1-benzyl-3-[2-(4-methoxyphenyl)-2-oxoethylidene]indolin-2-one, C24H19NO3, (IIc), or (E)-1-benzyl-5-chloro-3-[2-(4-chlorophenyl)-2-oxoethylidene]indolin-2-one, C23H15Cl2NO2, (IIh), but the molecules of (IIh) are linked into chains of π-stacked dimers by a combination of C—Cl⋯π(arene) and aromatic π–π stacking interactionPublisher PDFPeer reviewe
C–H.I− interactions in ferrocene derivatives: structures of (Ferrocenylmethyl)triphenylphosphonium iodide and 1,1'-ferrocenediylbis(methyltriphenylphosphonium iodide) dichloromethane solvate (1/1)
The cations in (ferrocenylmethyl)triphenylphosphonium
iodide, [{(C5H5)Fe(C5Ha)}CH2P(C6Hs)3]+.I -, (1), and
in 1, l'-ferrocenediylbis(methyltriphenylphosphonium
iodide) dichloromethane solvate, [Fe{(C5H4)CH2-
P(C6H5)3}212+.2I-.CH2C12, (2), are involved in three dimensional networks of C--H. • .I- interactions between
phenyl C--H groups and I- anions. In (1), the cation resides
in a general position while one I- anion is on a
twofold axis and a second I- anion is at an inversion
centre. The shortest C...I- distances are 3.886 (2) and
3.989 (2)A to the I- ion which resides on an inversion
centre. The cation in (2) has approximate mirror symmetry
and lies in a general position in the unit cell along
with its two I- anions. The shortest C--.I- interactions
are 3.810 (4) and 3.886 (5) A,
4-Styrylquinolines from cyclocondensation reactions between (2-aminophenyl)chalcones and 1,3-diketones : crystal structures and regiochemistry
Funding for this research was provided by: Vicerrectoría de Investigación y Extensión de la Universidad Industrial de Santander (proyecto No. 2497, to AP); Universidad de Jaén, the Consejería de Economía, Innovación, Ciencia y Empleo (Junta de Andalucía, Spain) and Centro de Instrumentación Científico–Técnica of the Universidad de Jaén (UJA) (to JC).Structures are reported for two matched sets of substituted 4-styrylquinolines which were prepared by the formation of the heterocyclic ring in cyclocondensation reactions between 1-(2-aminophenyl)-3-arylprop-2-en-1-ones with 1,3-dicarbonyl compounds. (E)-3-Acetyl-4-[2-(4-methoxyphenyl)ethenyl]-2-methylquinoline, C21H19NO2, (I), (E)-3-acetyl-4-[2-(4-bromophenyl)ethenyl]-2-methylquinoline, C20H16BrNO, (II), and (E)-3-acetyl-2-methyl-4-{2-[4-(trifluoromethyl)phenyl]ethenyl}quinoline, C21H16F3NO, (III), are isomorphous and in each structure the molecules are linked by a single C—H...O hydrogen bond to form C(6) chains. In (I), but not in (II) or (III), this is augmented by a C—H...π(arene) hydrogen bond to form a chain of rings; hence, (I)–(III) are not strictly isostructural. By contrast with (I)–(III), no two of ethyl (E)-4-[2-(4-methoxyphenyl)ethenyl]-2-methylquinoline-3-carboxylate, C22H21NO3, (IV), ethyl (E)-4-[2-(4-bromophenyl)ethenyl]-2-methylquinoline-3-carboxylate, C21H18BrNO2, (V), and ethyl (E)-2-methyl-4-{2-[4-(trifluoromethyl)phenyl]ethenyl}quinoline-3-carboxylate, C22H18F3NO2, (VI), are isomorphous. The molecules of (IV) are linked by a single C—H...O hydrogen bond to form C(13) chains, but cyclic centrosymmetric dimers are formed in both (V) and (VI). The dimer in (V) contains a C—H...π(pyridyl) hydrogen bond, while that in (VI) contains two independent C—H...O hydrogen bonds. Comparisons are made with some related structures, and both the regiochemistry and the mechanism of the heterocyclic ring formation are discussed.Publisher PDFPeer reviewe
Crystal structures of two C,N-disubstituted acetamides: 2-(4-chlorophenyl)-N-(2-iodophenyl)acetamide and 2-(4-chlorophenyl)-N-(pyrazin-2-yl)acetamide
BN thanks the UGC (India) for financial assistance through a BSR one-time grant for the purchase of chemicals.In the crystal of 2-(4-chlorophenyl)-N-(2-iodophenyl)acetamide, C14H11ClINO, molecules are linked by a combination of N—H⋯O and C—H⋯O hydrogen bonds to form a C(4)C(4)[R21(7)] chain of rings and chains of this type are linked by a combination of C—Cl⋯π(arene) and C—I⋯π(arene) interactions to form deeply puckered twofold interwoven sheets. In the crystal of 2-(4-chlorophenyl)-N-(pyrazin-2-yl)acetamide, C12H10ClN3O, molecules are linked into complex sheets by N—H⋯N, C—H⋯N and C—H⋯O hydrogen bonds, and by C—H⋯π(arene) interactions.Publisher PDFPeer reviewe
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