Crystal structures of potassium trifluorido(4-methoxyphenyl)borate and potassium trifluorido(4-fluorophenyl)borate

Abstract

The title compounds, K+·C7H7BF3O−, (I), and K+·C6H4BF4−, (II), are molecular salts containingpara-substituted phenyltrifluoridoborate anions. In each compound, the B atom adopts a distorted tetrahedral BCF3geometry. Despite their different compositions and space groups, the irregular KF8coordination polyhedra of the potassium cations in the structures are almost identical. These polyhedra share faces and edges, generating infinite (010) layers in (I) and infinite (001) layers in (II). In (I), adjacent layers are stacked in anAAA… fashion, whereas in (II), they are stacked in anABAB… sequence.