Methyl 4-(4-bromo-anilino)-2',5-dioxo-5H-spiro-[furan-2,3'-indoline]-3-carboxyl-ate

In the title compound, C₁₉H₁₃BrN₂O₅, the spiro furan ring is almost planar with a maximum deviation of 0.034 (2) Å. The indole unit and the furan ring are normal to each other, making a dihedral angle of 87.82 (8) °. The mol­ecular structure is stabilized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol­ecules are linked via pairs of N—H⋯O hydrogen bonds, forming inversion dimers enclosing R²₂(8) ring motifs.

Methyl 4-anilino-2',5-dioxo-1',2'-di-hydro-5H-spiro-[furan-2,3'-indole]-3-carboxyl-ate

In the title compound, C₁₉H₁₄N₂O₅, the spiro junction links an oxindole moeity and a furan ring, which subtend a dihedral angle of 83.49 (6)°. The mol­ecular structure features an N—H⋯O hydrogen bond, which generates an S(6) ring motif. The crystal packing is governed by two N—H⋯O inter­actions, one of which generates a centrosymmetric R₂²(14) dimer. The other N—H⋯O inter­action along with a C—H⋯O hydrogen bond contributes to the formation of a C₂²[R₂²(9)] dimeric chain running along the b-axis direction.

Multicomponent assembly of 2-amino-4-substituted 4H-chromenes using cyclic Michael donors

An efficient one-pot synthesis has been disclosed to access a series of 2-amino-4-substituted 4H-chromenes from salicylaldehyde, malononitrile, and a few cyclic nucleophiles using indium trichloride as a catalyst. This methodology affords high yields of products in a shorter reaction time.