Anthonisamy Devaraj

Synthesis of highly diversified 1,2,3-triazole derivatives via domino [3 + 2] azide cycloaddition and denitration reaction sequence

In this paper, an elegant synthesis of 1,2,3-triazole derivatives via domino [3 + 2] azide cycloaddition and denitration reaction sequence under catalyst free conditions has been described. Treatment of Baylis–Hillman adducts and their cyclic derivatives from nitroolefins with sodium azide in the absence of catalyst smoothly afforded the 1,2,3-triazole derivatives in excellent yields.

(E)-Methyl 2-benzyl-3-o-tolyl­acrylate

In the title compound, C18H18O2, the methyl acrylate substituent adopts an extended E conformation with all torsion angles close to 180°. The mean plane of the acrylate unit and the phenyl ring are approximately orthogonal to each other, making a dihedral angle of 81.40 (6)°. The position of the carbonyl group with respect to the olefinic double bond is typically S-trans. The crystal packing is stabilized by intermolecular C—H⋯π interactions.

Methyl 4'-(3-bromo-phen-yl)-3'-(2,5-di-methyl-benz-yl)-1'-methyl-2-oxo-spiro-[indo-line-3,2'-pyrrolidine]-3'-carboxyl-ate.

In the title compound, C29H29BrN2O3, the indole ring system is essentially planar (r.m.s. deviation = 0.079 Å) and makes a dihedral angle of 85.23 (10)° with the mean plane of the 4-methylpyrrolidine ring. This ring adopts an envelope conformation with the N atom at the flap. The pyrrolidine ring of the indole ring system adopts a twisted conformation on the C—C(=O) bond. The molecular structure is stabilized by an intramolecular C—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked via pairs of C—H⋯O hydrogen bonds, forming inversion dimers with an R 2 2(14) ring motif. These dimers are further linked by N—H⋯O and C—H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to (10-1).

Methyl (2Z)-2-bromo­methyl-3-(2,4-dichloro­phen­yl)prop-2-enoate

In the title compound C11H9BrCl2O2, which represents the Z isomer, the methylacrylate moiety is essentially planar within 0.039 (2) Å and has an extended trans configuration. The benzene ring makes a dihedral angle of 28.3 (1)° with the mean plane of the methylacrylate moiety. The crystal packing is characterized by C—H⋯O hydrogen bonding and halogen–halogen interactions [Cl⋯Cl = 3.486 (3) Å], resulting in the formation of R 2 2(11) ring motifs and connecting the molecules into chains propagating along the b axis.

Methyl (E)-2-[(2-nitro­phen­oxy)meth­yl]-3-phenyl­acrylate

The title compound, C17H15NO5, adopts an E conformation with respect to the C=C double bond of the phenylacrylate unit. The phenyl ring and methyl acrylate group of the phenylacrylate unit are disordered over two sets of sites with site-occupancy ratios of 0.705 (5):0.295 (5) and 0.683 (3):0.317 (3), respectively. The mean plane through the benzene ring of the phenyl acrylate makes dihedral angles of 88.4 (8) (major component) and 86.7 (8)° (minor component) with the nitrophenoxy ring; the dihedral angle between the two components is 3.64 (6)°. Intramolecular C—H⋯O interactions stabilise the molecular structure. In the crystal, C—H⋯O interactions result in a chain of molecules running along the b axis.

2-[(6-Nitro-1,3-benzodioxol-5-yl)methyl-idene]malononitrile.

In the title compound, C11H5N3O4, the nitro group is rotated by 29.91 (16)° out of the plane of the adjacent aryl ring. The 1,3-benzodioxole ring is nearly planar, with a maximium deviation of 0.0562 (10) Å. The dioxolene ring adopts an envelope conformation on the O—C—O C atom. In the crystal, molecules are linked via C—H⋯O interactions, resulting in R 2 2(6) and R 2 2(12) graph-set motifs.

Methyl 3′-(2,5-di­methyl­benz­yl)-1′-methyl-2-oxo-4′-phenyl­spiro­[indoline-3,2′-pyrrolidine]-3′-carboxyl­ate chloro­form monosolvate

In the title solvate, C29H30N2O3·CHCl3, the dihedral angle between the indole ring system (r.m.s. deviation = 0.050 Å) and the 4-methylpyrrolidine ring is 88.88 (8)°. The latter ring adopts an envelope conformation with the N atom as the flap. Its mean plane makes dihedral angles of 86.94 (11) and 42.08 (9)° with the phenyl and dimethylbenzene rings, respectively. The molecular conformation is stabilized by intramolecular C—H⋯O hydrogen bonds, which generate S(6) and S(9) ring motifs. The chloroform solvent molecule is linked to the organic molecule by a C—H⋯O hydrogen bond involving the carbonyl O atom of the carboxylate group. In the crystal, molecules are linked via bifurcated N—H⋯(N,O) and C—H⋯O hydrogen bonds, forming chains propagating along [001].

Methyl 3′-benzyl-4′-(2-chloro­phen­yl)-1′-methyl-2-oxo­spiro­[indoline-3,2′-pyrrolidine]-3′-carboxyl­ate

In the title compound, C27H25ClN2O3, the methylpyrrolidine ring adopts an envelope conformation with the N atom at the flap. The mean plane of the pyrrolidine ring makes dihedral angles of 82.1 (1), 84.4 (1) and 79.8 (1)°, respectively, with the adjacent benzene ring, the mean plane of the indoline ring system and the phenyl ring. The molecular structure is stabilized by intramolecular C—H⋯O hydrogen bonds. In the crystal, molecules are linked into chains along [101] by N—H⋯O hydrogen bonds. C—H⋯π interactions are observed between the chains.

2,2'-Diisopropoxy-5,5'-methyl-enedi-benz-alde-hyde.

Molecules of the title compound, C21H24O4, are located on a twofold rotation axis running through the central methylene C atom. The aldehyde group is coplanar with the benzene ring [C—C—C—O = 175.7 (4) °].

(E)-3-(1,3-Benzodioxol-5-yl)-2-{[N-(2-formylphenyl)-4-methylbenzenesulfon-amido]methyl}prop-2-enenitrile.

In the title compound, C25H20N2O5S, the benzodioxole ring system is essentially planar [maximum deviation = 0.021 (2) Å] and forms dihedral angles of 85.2 (1) and 74.2 (1)°, respectively, with the formyl benzene and sulfonyl-bound benzene rings. In the crystal, C—H⋯O hydrogen bonds generate C(8) chains along [100] and R33(19) ring motifs. In addition, a weak π–π interaction [centroid–centroid distance = 3.937 (3) Å] is also observed.