Crystal structures of N,N-dimethyl-(2-(2,2-diphen-yl)-2-prop-2-yn-yloxy)acet-oxy)ethyl-amine and N,N-dimethyl-(2-(2,2-diphen-yl)-2-prop-2-yn-yl--oxy)acet-oxy)ethyl-ammonium 2,4,6-tri-nitro-phenolate.

The N,N-di-methyl-ethylamminium unit in N,N-dimethyl-[2-(2,2-diphen-yl)-2-prop-2-ynyloxyacet-oxy]ethyl-amine, C21H23NO3 (I), is disordered over two sets of atomic sites having occupancies of 0.880 (3) and 0. 120 (3), but there are no direction-specific inter-actions between the mol-ecules of (I). The cation in N,N-dimethyl-[2-(2,2-diphen-yl)-2-prop-2-ynyloxyacet-oxy]ethyl-ammonium 2,4,6-tri-nitro-phenolate (picrate), C21H24NO3+·C6H2N3O7- (II), shows a similar type of disorder, with occupancies of 0.654 (11) and 0.346 (11), although the overall conformation of the cation in (II) is different from that in the neutral (I). The component ions are are linked by an almost planar three-centre N-H⋯(O)2 hydrogen bond, and the ion pairs are further linked by a combination of three C-H⋯O hydrogen bonds to form sheets. Comparisons are made with some related structures.