Radhakrishnan Sureshbabu

Lewis Acid-Mediated Michaelis−Arbuzov Reaction at Room Temperature: A Facile Preparation of Arylmethyl/Heteroarylmethyl Phosphonates

A facile preparation of arylmethyl and heteroarylmethyl phosphonate esters was achieved involving a Lewis acid mediated Michaelis-Arbuzov reaction at room temperature. Interaction of arylmethyl halides/alcohols with triethyl phosphite in the presence of Lewis acid at room temperature afforded phosphonate esters in good yields.

Synthesis of 3-Indolylpyrroles via Base-Mediated Cycloaddition of TOSMIC with Activated Indole-2/3-vinylenes

Abstract A synthesis of various types of 3-indolylpyrroles is reported involving a base-mediated 1,3-dipolar cycloaddition of TOSMIC with activated indole-2/3-vinylenes.

Diethyl 3,4-bis(acetoxy-meth-yl)thieno[2,3-b]thio-phene-2,5-dicarboxyl-ate.

In the title compound, C18H20O8S2, the dihedral angle between the two thiophene rings is 2.33 (7)°. The methyl C atoms of the ester groups are disordered over two positions; the site-occupancy factors of the terminal methyl C atoms are 0.632 (18):0.368 (18) and 0.623 (17):0.377 (17). The molecular structure is stabilized by weak intramolecular C—H⋯O interactions and the crystal structure is stabilized through weak intermolecular C—H⋯O interactions.

Ethyl 2-[N-(2-formylphenyl)benzenesulfonamido]acetate

In the molecule of the title compound, C17H17NO5S, the two aromatic rings are oriented at an angle of 30.13 (10)°. The ethyl acetate group assumes an extended conformation. Molecules are linked into C(7) chains running along the a axis by intermolecular C—H⋯O hydrogen bonds, and the chains are crosslinked via C—H⋯π interactions, with the sulfonyl-bound phenyl ring acting as an acceptor.

Diethyl 3,4-bis­(2,5-dimethoxy­benz­yl)thieno[2,3-b]thio­phene-2,5-di­car­boxylate

In the title compound, C30H32O8S2, the dihedral angle between the two benzene rings is 18.8 (1)°. The molecular structure is stabilized by weak intramolecular C—H⋯O hydrogen bonds. In the crystal structure, the molecules are linked via weak intermolecular C—H⋯O hydrogen bonds and π–π interactions between two benzene rings [centroid–centroid distance = 3.672 (1) Å].

2,5-Dimethyl-1-phenyl­sulfonyl-1H-pyrrole-3,4-dicarbaldehyde

In the title compound, C14H13NO4S, the mean planes of the pyrrole and phenyl rings form a dihedral angle of 88.7 (1)°. The aldehyde groups are slightly twisted from the pyrrole plane. In the crystal structure, molecules are linked into a three-dimensional framework by C—H⋯O hydrogen bonds.

Ethyl 2-acetoxy-methyl-1-phenyl-sulfonyl-1H-indole-3-carboxyl-ate.

In the title compound, C20H19NO6S, the phenyl ring of the phenylsulfonyl group makes a dihedral angle of 83.35 (5)° with the indole ring system. The molecular structure exhibits a number of short intramolecular C—H⋯O contacts.

4-Bromo­meth­yl-1-phenyl­sulfon­yl-1H-indole

In the title molecule, C15H12BrNO2S, the indole mean plane and phenyl ring are nearly orthogonal to each other, forming a dihedral angle of 88.19 (13)°. The Br atom is disordered over two close positions with occupancies of 0.56 (4) and 0.44 (4). The crystal packing exhibits weak intermolecular C—H⋯π interactions.

Ethyl 2-(3,4-dimethoxy­benz­yl)-1-phenyl­sulfonyl-1H-indole-3-carboxyl­ate

In the title compound, C26H25NO6S, the phenyl ring forms a dihedral angle of 82.5 (1)° with the indole ring system. The molecular structure is stabilized by weak intramolecular C—H⋯O interactions and the crystal structure is stabilized by weak intermolecular C—H⋯O interactions.

Trimethyl 1-(2-methyl-1-phenylsulfonyl-1H-indol-3-yl)propane-1,2,3-tricarbox-ylate.

In the title compound, C24H25NO8S, the indole unit is planar and makes a dihedral angle of 79.73 (11)° with the phenyl ring of the sulfonyl substituent. The molecules in the unit cell are stabilized by C—H⋯O and C—H⋯π intermolecular interactions in addition to van der Waals forces.