3-(Di-phenyl-amino)-isobenzo-furan-1(3H)-one

3-Amino-4-(diphenylamino)-1H-2-benzopyran-1-one

Various synthetic methodologies to obtain 3,4-diaminoisocumarin nucleus have been reported and described. However, mechanistic analysis based on experimental evidence is lacking. Herein, we report the synthesis of the novel 3-amino-4-(diphenylamino)-1H-2-benzopyran-1-one using a two-step methodology with a new mechanistic proposal to explain the formation of the latter based on previously reported precursors and the established conditions. This compound was afforded in 80% yield.

Crystal structure of (±)-3-[(benzo[d][1,3]dioxol-5-yl)meth-yl]-2-(3,4,5-tri-meth-oxy-phen-yl)-1,3-thia-zolidin-4-one

In the title thia-zolidine-4-one derivative, C20H21NO6S, the central thia-zolidine ring is essentially planar (r.m.s. deviation for all non-H atoms = 0.0287 Å) and forms a dihedral angle of 88.25 (5)° with the meth-oxy-substituted benzene ring and 74.21 (4)° with the 1,3-benzodioxole ring. The heterocyclic ring (with two O atoms) fused to benzene ring adopts an envelope conformation with the non-ring-junction C atom as the flap. In the crystal, the mol-ecules are linked into chains along [001] through weak C-H⋯O inter-actions, forming R (4) 4(28) edge-fused rings.