Syntheses and molecular structures of 2- [1′- N-(alkyl)imino-2′,2′,2′-trifluoroethyl] phenols

Abstract

N-(Alkyl)imino derivatives of trifluoroacetyl phenol of the general formula 1,2-C 6H 4[C(=NR)CF 3] [OH] (R = H, 3a; Me, 3b; nPr, 3c; iPr, 3d; CH 2CH 2NH 2, 3e; CH 2CH 2CH 2NH 2, 3f; CH 2CH 2CH 2CH 2NH 2, 3g; CH 2CH 2OH, 3h; CH 2CH 2NMe 2, 3i) were synthesized from 2- trifluoroacetyl phenol and the corresponding primary amines RNH 2. The molecular structures of 3b [monoclinic, P2 1/ n, a = 6.641(3), b= 18.044(8), c = 7.716(3) Å, β = 99.95(4)°], 3d [orthorhombic, P2 12 12 1, a = 7.784(2), b = 9.291(2), c = 15.942(4) Å] and 3i [mono- clinic, P2 1/ n, a = 8.660(2), b = 18.135(2), c = 13.300(2) Å, β = 99.83 (2)°] were determined. In the solid state, 3b, 3d and 3i exist exclusively as E isomers with intermolecular hydrogen bridges, whereas according to the 1H and 19F NMR spectra in chloroform solution, compounds 3b, 3c and 3d isomerize to give a mixture of 66% Z and 34% E isomers.