Crystal structures of N-tert-butyl-3-(4-fluoro­phenyl)-5-oxo-4-[2-(tri­fluoro­meth­oxy)phen­yl]-2,5-di­hydro­furan-2-carboxamide and 4-(2H-1,3-benzodioxol-5-yl)-N-cyclo­hexyl-5-oxo-3-[4-(tri­fluoro­meth­yl)phen­yl]-2,5-di­hydro­furan-2-carboxamide

The title compounds, C(22)H(19)F(4)NO(4), (I), and C(25)H(22)F(3)NO(5), (II), each contain a central nearly planar di­hydro­furan­one ring. The r.m.s. deviation from planarity of these rings is 0.015 Å in (I) and 0.027 Å in (II). The mol­ecules are T-shaped, with the major conformational difference being the O—C—C—O torsion angle [−178.9 (1) in (I) and 37.7 (2)° in (II)]. In the crystal of (I), mol­ecules are linked by N—H⋯O hydrogen bonds, forming chains along [001] while in (II) mol­ecules are linked by N—H⋯O hydrogen bonds, forming chains along [010]. In (II), the tri­fluoro­methyl substituent is disordered over two sets of sites, with refined occupancies of 0.751 (3) and 0.249 (3).