Pseudoacids. II. 2-Acylbenzoic Acid Derivatives

Abstract

Structures of derivatives of cyclic o-acylbenzoic acids, including the chloride, endo- and exocyclic amides, esters and anhydrides, are examined. 3-Chloro-1(3H)-isobenzofuranone (1), orthorhombic, Pbca, a = 11.616 (5), b = 8.120 (3), c = 15.640 (9) Å; 3-methoxy-3-phenyl-1(3H)-isobenzofuranone (3), orthorhombic, P212121, a = 6.923 (2), b = 8.291 (4), c = 21.551 (8) Å; 3-hydroxy-3-phenyl-N-propyl-1(3H)-isoindolone (4), orthorhombic, P212121, a = 8.662 (4), b = 9.551 (7), c = 17.649 (14) Å; 3-(N-morpholino)-1(3H)-isobenzofuranone (5), triclinic, P1¯, a = 6.172 (4), b = 11.163 (7), c = 17.33 (2) Å, α = 105.91 (6), β = 99.85 (6), γ = 97.57 (5)°; 3-(2′-benzoylbenzoyloxy)-3-phenyl-1(3H)-isobenzofuranone (7), triclinic, P1¯, a = 9.694 (3), b = 10.505 (4), c = 11.163 (4) Å, α = 80.58 (3), β = 80.41 (3), γ = 76.49 (3)°; bis[1(3H)-isobenzofuranone-3-yl]ether (8), monoclinic, I2/a, a = 15.31 (2), b = 6.111 (12), c = 28.30 (5) Å, β = 101.61 (12)°. An open oxoacid tertiary amide is also described: N-morpholino 2′-benzoylbenzamide (6): monoclinic, P21/c, a = 6.844 (4), b = 15.696 (8), c = 14.154 (7) Å, β = 99.43 (4)°. Pseudoacid derivatives form planar isobenzofuran and isoindole rings, and the former aldehyde/ketone carbon–heteroatom endocyclic and exocyclic bond distances show bond length variations which correlate with the relative basicities of the attached groups. Structures of both endocyclic and exocyclic nitrogen pseudoamides are reported as well as examples of the normal–pseudoanhydride and the dipseudoanhydride.