In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1... more In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C21H19F4N3O2S, (I), 1-(4-chlorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C21H19ClF3N3O2S, (II), and 1-(3-methylphenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C22H22F3N3O2S, (III), the reduced pyridine ring adopts a half-chair conformation with the methylsulfonyl substituent occupying an equatorial site. Although compounds (I) and (II) are not isostructural, having the space groups Pbca and P212121, respectively, their molecular conformations are very similar, but the conformation of compound (III) differs from those of (I) and (II) in the relative orientation of the N-benzyl and methylsulfonyl substituents. In compounds (II) and (III), but not in (I), the trifluoromethyl groups are disordered over two sets of atomic sites. Molecules of (I) are link...
Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond... more Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond-donor NH unit in pyrazole by a potential hydrogen-bond-acceptor O atom in isoxazole. It is thus of interest to compare the hydrogen-bonding characteristics of these rings. (4-Fluorophenyl)pyrazole undergoes protonation in the presence of 2,4,6-trinitrophenol to yield the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate, C9H8FN2(+)·C6H2N3O7(-), (I), whereas there is no proton transfer between 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide and 3,5-dinitrobenzoic acid, whose reaction gives the 1:1 cocrystal, C11H13N3O3S·C7H4N2O6, (II). The bond lengths in salt (I) provide evidence for aromatic-type delocalization in the pyrazolium ring and for extensive delocalization of the negative charge into the ring of the trinitrophenolate anion. The O atoms of one of the nitro groups in the trinitrophenolate anion are disordered over two sets of atomic sites having occupanci...
Four compounds are reported, all of which lie along a versatile reaction pathway which leads from... more Four compounds are reported, all of which lie along a versatile reaction pathway which leads from simple carbonyl compounds to terphenyls. (2E)-1-(2,4-Dichlorophenyl)-3- [4-(prop-1-en-2-yl)phenyl]prop-2-en-1-one, C18H14Cl2O, (I), prepared from 4-(prop-1-en-2-yl)benzaldehyde and 2,4-dichloroacetophenone, exhibits disorder over two sets of atomic sites having occupancies of 0.664 (6) and 0.336 (6). The related chalcone (2E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one reacts with acetone to produce (5RS)-3-(4-chlorophenyl)-5-[4-(propan-2-yl)phenyl]cyclohex-2-en-1-one, C21H21ClO, (II), which exhibits enantiomeric disorder with occupancies at the reference site of 0.662 (4) and 0.338 (4) for the (5R) and (5S) forms; the same chalcone reacts with methyl 3-oxobutanoate to give methyl (1RS,6SR)-4-(4-chlorophenyl)-6-[4-(propan-2-yl)phenyl]-2-oxocyclohex-3-ene-1-carboxylate, C23H23ClO3, (III), where the reference site contains both (1R,6S) and (1S,6R) forms with occupancies of 0.923 ...
Acta crystallographica. Section E, Structure reports online, 2014
In the title compound, C22H19ClN2O3S, the dihedral angle between the mean planes of the thio-phen... more In the title compound, C22H19ClN2O3S, the dihedral angle between the mean planes of the thio-phene ring and the chloro-phenyl and hy-droxy-phenyl rings are 70.1 (1) and 40.2 (4)°, respectively. The benzene rings are twisted with respect to each other by 88.9 (3)°. The imine bond lies in an E conformation. Intra-molecular O-H⋯N and N-H⋯O hydrogen bonds each generate S(6) ring motifs. In the crystal, weak C-H⋯O inter-actions link the mol-ecules, forming chains along the c axis and zigzag chains along the b axis, generating sheets lying parallel to (100).
Acta Crystallographica Section E Structure Reports Online, 2013
The title compound, C19H19N3O2, crystallizes with two independent molecules (AandB) in the asymme... more The title compound, C19H19N3O2, crystallizes with two independent molecules (AandB) in the asymmetric unit. In moleculeA, the pyrazole ring adopts a slightly disordered half-chair conformation while inBit is planar [r.m.s. deviation = 0.0386 (15) Å]. The dihedral angle between the mean planes of the two phenyl rings is 56.2 (8) inAand 38.2 (3)° inB. TheN-phenyl substituent on the pyrazole ring is twisted by 46.5 (2) inAand 58.6 (4)° inBwhile the extended phenyl ring is twisted by 82.2 (8) inAand 87.5 (9)° inB. The mean plane of the amide group forms an angle of 74.8 (3) inAand 67.7 (1)° inBwith respect to the phenyl ring. In addition, the amide group is rotated by 51.4 (1) inAand 53.6 (2)° inBfrom the the mean plane of the pyrazole ring. In the crystal, the two molecules are linkedviaN—H...O hydrogen bonds, supported by weak C—H...O interactions, forming dimers enclosing anR22(10) ring motif. The dimers are linkedviaC—H...O interactions, forming a three-dimensional structure.
Acta Crystallographica Section E Structure Reports Online, 2007
In the title compound, C17H12Br3Cl2NO, the mean planes of the 3,5-dibromo-4-phenyl and 2,4-dichlo... more In the title compound, C17H12Br3Cl2NO, the mean planes of the 3,5-dibromo-4-phenyl and 2,4-dichlorophenyl groups make a dihedral angle of 72.4 (2)°. The dihedral angles between the 2-bromoprop-2-en-1-one group and the two phenyl ring groups (3,5-dibromo-4-phenyl and 2,4-dichlorophenyl) are 71.1 (1) and 10.9 (4)°, respectively. The crystal packing is stabilized by intermolecular N—H...O hydrogen-bond interactions between the ethylamino H atom and the propyl ketone O atom, with the 3,5-dibromo-4-phenyl rings linked in chains in an alternate inverted pattern parallel and oblique to the ac face and diagonally along the a axis of the unit cell. An intramolecular hydrogen bond between the ethyl amino H atom and the 5-Br atom from the 3,5-dibromo-4-phenyl group helps stabilize the molecular conformation.
Acta Crystallographica Section E Structure Reports Online, 2007
In the title molecule, C19H19Cl2NO2, the angle between the mean planes of the 2,4-dichlorophenyl ... more In the title molecule, C19H19Cl2NO2, the angle between the mean planes of the 2,4-dichlorophenyl and 2-hydroxyphenyl groups is 81.8 (2)°. The ketone oxygen of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichlorophenyl group [torsion angle = −75.7 (2)°]. The two diethyl extensions from the 4-(diethylamino)-2-hydroxyphenyl group are twisted in anti- and syn-periplanar conformations. Crystal packing is stabilized by intermolecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and H atoms from both the 2-hydroxyphenyl ring and the hydroxy group; these hydrogen bonds link the molecules into chains along the diagonal of the bc face of the unit cell. The 2-hydroxyphenyl rings are stacked obliquely parallel to the ab face while the 2,4-dichlorophenyl rings are stacked obliquely parallel to the bc face of the unit cell, each in an inverted conformation. Additional intermolecular packing interactions occur between π orbital...
Acta Crystallographica Section E Structure Reports Online, 2007
In the title molecule, C18H14Cl4O2, the angle between the mean planes of the 3,5-dichloro-4-metho... more In the title molecule, C18H14Cl4O2, the angle between the mean planes of the 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups is 47.6 (2)°. The 4-methoxy group, with a torsion angle of 91.9 (9)°, is twisted away from the plane of the 3,5-dichloro-2,6-dimethylphenyl ring in an anticlinal conformation. The ketone O atom of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichlorophenyl group [torsion angle = 45.5 (11)°]. The crystal packing is stabilized by intermolecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and an H atom from a nearby 2,4-dichlorophenyl group, which link the molecules into chains along the a axis. The 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups are aligned obliquely parallel to the ac face, with the benzene rings stacked obliquely along the b axis for both groups.
In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1... more In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C21H19F4N3O2S, (I), 1-(4-chlorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C21H19ClF3N3O2S, (II), and 1-(3-methylphenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C22H22F3N3O2S, (III), the reduced pyridine ring adopts a half-chair conformation with the methylsulfonyl substituent occupying an equatorial site. Although compounds (I) and (II) are not isostructural, having the space groups Pbca and P212121, respectively, their molecular conformations are very similar, but the conformation of compound (III) differs from those of (I) and (II) in the relative orientation of the N-benzyl and methylsulfonyl substituents. In compounds (II) and (III), but not in (I), the trifluoromethyl groups are disordered over two sets of atomic sites. Molecules of (I) are link...
Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond... more Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond-donor NH unit in pyrazole by a potential hydrogen-bond-acceptor O atom in isoxazole. It is thus of interest to compare the hydrogen-bonding characteristics of these rings. (4-Fluorophenyl)pyrazole undergoes protonation in the presence of 2,4,6-trinitrophenol to yield the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate, C9H8FN2(+)·C6H2N3O7(-), (I), whereas there is no proton transfer between 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide and 3,5-dinitrobenzoic acid, whose reaction gives the 1:1 cocrystal, C11H13N3O3S·C7H4N2O6, (II). The bond lengths in salt (I) provide evidence for aromatic-type delocalization in the pyrazolium ring and for extensive delocalization of the negative charge into the ring of the trinitrophenolate anion. The O atoms of one of the nitro groups in the trinitrophenolate anion are disordered over two sets of atomic sites having occupanci...
Four compounds are reported, all of which lie along a versatile reaction pathway which leads from... more Four compounds are reported, all of which lie along a versatile reaction pathway which leads from simple carbonyl compounds to terphenyls. (2E)-1-(2,4-Dichlorophenyl)-3- [4-(prop-1-en-2-yl)phenyl]prop-2-en-1-one, C18H14Cl2O, (I), prepared from 4-(prop-1-en-2-yl)benzaldehyde and 2,4-dichloroacetophenone, exhibits disorder over two sets of atomic sites having occupancies of 0.664 (6) and 0.336 (6). The related chalcone (2E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)prop-2-en-1-one reacts with acetone to produce (5RS)-3-(4-chlorophenyl)-5-[4-(propan-2-yl)phenyl]cyclohex-2-en-1-one, C21H21ClO, (II), which exhibits enantiomeric disorder with occupancies at the reference site of 0.662 (4) and 0.338 (4) for the (5R) and (5S) forms; the same chalcone reacts with methyl 3-oxobutanoate to give methyl (1RS,6SR)-4-(4-chlorophenyl)-6-[4-(propan-2-yl)phenyl]-2-oxocyclohex-3-ene-1-carboxylate, C23H23ClO3, (III), where the reference site contains both (1R,6S) and (1S,6R) forms with occupancies of 0.923 ...
Acta crystallographica. Section E, Structure reports online, 2014
In the title compound, C22H19ClN2O3S, the dihedral angle between the mean planes of the thio-phen... more In the title compound, C22H19ClN2O3S, the dihedral angle between the mean planes of the thio-phene ring and the chloro-phenyl and hy-droxy-phenyl rings are 70.1 (1) and 40.2 (4)°, respectively. The benzene rings are twisted with respect to each other by 88.9 (3)°. The imine bond lies in an E conformation. Intra-molecular O-H⋯N and N-H⋯O hydrogen bonds each generate S(6) ring motifs. In the crystal, weak C-H⋯O inter-actions link the mol-ecules, forming chains along the c axis and zigzag chains along the b axis, generating sheets lying parallel to (100).
Acta Crystallographica Section E Structure Reports Online, 2013
The title compound, C19H19N3O2, crystallizes with two independent molecules (AandB) in the asymme... more The title compound, C19H19N3O2, crystallizes with two independent molecules (AandB) in the asymmetric unit. In moleculeA, the pyrazole ring adopts a slightly disordered half-chair conformation while inBit is planar [r.m.s. deviation = 0.0386 (15) Å]. The dihedral angle between the mean planes of the two phenyl rings is 56.2 (8) inAand 38.2 (3)° inB. TheN-phenyl substituent on the pyrazole ring is twisted by 46.5 (2) inAand 58.6 (4)° inBwhile the extended phenyl ring is twisted by 82.2 (8) inAand 87.5 (9)° inB. The mean plane of the amide group forms an angle of 74.8 (3) inAand 67.7 (1)° inBwith respect to the phenyl ring. In addition, the amide group is rotated by 51.4 (1) inAand 53.6 (2)° inBfrom the the mean plane of the pyrazole ring. In the crystal, the two molecules are linkedviaN—H...O hydrogen bonds, supported by weak C—H...O interactions, forming dimers enclosing anR22(10) ring motif. The dimers are linkedviaC—H...O interactions, forming a three-dimensional structure.
Acta Crystallographica Section E Structure Reports Online, 2007
In the title compound, C17H12Br3Cl2NO, the mean planes of the 3,5-dibromo-4-phenyl and 2,4-dichlo... more In the title compound, C17H12Br3Cl2NO, the mean planes of the 3,5-dibromo-4-phenyl and 2,4-dichlorophenyl groups make a dihedral angle of 72.4 (2)°. The dihedral angles between the 2-bromoprop-2-en-1-one group and the two phenyl ring groups (3,5-dibromo-4-phenyl and 2,4-dichlorophenyl) are 71.1 (1) and 10.9 (4)°, respectively. The crystal packing is stabilized by intermolecular N—H...O hydrogen-bond interactions between the ethylamino H atom and the propyl ketone O atom, with the 3,5-dibromo-4-phenyl rings linked in chains in an alternate inverted pattern parallel and oblique to the ac face and diagonally along the a axis of the unit cell. An intramolecular hydrogen bond between the ethyl amino H atom and the 5-Br atom from the 3,5-dibromo-4-phenyl group helps stabilize the molecular conformation.
Acta Crystallographica Section E Structure Reports Online, 2007
In the title molecule, C19H19Cl2NO2, the angle between the mean planes of the 2,4-dichlorophenyl ... more In the title molecule, C19H19Cl2NO2, the angle between the mean planes of the 2,4-dichlorophenyl and 2-hydroxyphenyl groups is 81.8 (2)°. The ketone oxygen of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichlorophenyl group [torsion angle = −75.7 (2)°]. The two diethyl extensions from the 4-(diethylamino)-2-hydroxyphenyl group are twisted in anti- and syn-periplanar conformations. Crystal packing is stabilized by intermolecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and H atoms from both the 2-hydroxyphenyl ring and the hydroxy group; these hydrogen bonds link the molecules into chains along the diagonal of the bc face of the unit cell. The 2-hydroxyphenyl rings are stacked obliquely parallel to the ab face while the 2,4-dichlorophenyl rings are stacked obliquely parallel to the bc face of the unit cell, each in an inverted conformation. Additional intermolecular packing interactions occur between π orbital...
Acta Crystallographica Section E Structure Reports Online, 2007
In the title molecule, C18H14Cl4O2, the angle between the mean planes of the 3,5-dichloro-4-metho... more In the title molecule, C18H14Cl4O2, the angle between the mean planes of the 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups is 47.6 (2)°. The 4-methoxy group, with a torsion angle of 91.9 (9)°, is twisted away from the plane of the 3,5-dichloro-2,6-dimethylphenyl ring in an anticlinal conformation. The ketone O atom of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichlorophenyl group [torsion angle = 45.5 (11)°]. The crystal packing is stabilized by intermolecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and an H atom from a nearby 2,4-dichlorophenyl group, which link the molecules into chains along the a axis. The 3,5-dichloro-4-methoxy-2,6-dimethylphenyl and 2,4-dichlorophenyl groups are aligned obliquely parallel to the ac face, with the benzene rings stacked obliquely along the b axis for both groups.
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