Crystal structure of L-leucyl-L-isoleucine 2,2,2-tri­fluoro­ethanol monosolvate

Hydro­phobic dipeptides with either L-Leu or L-Phe constitute a rather heterogeneous group of crystal structures. Some form materials with large water-filled channels, but there is also a pronounced tendency to incorporate organic solvent mol­ecules, which then act as acceptors for one of the three H atoms of the charged N-terminal amino group. L-Leu-L-Ile has uniquely been obtained as two distinct hydrates, but has so far failed to co-crystallize with a simple alcohol. The present structure of C12H24N2O3·CF3CH2OH, which crystallizes with two dipeptide and two solvent mol­ecules in the asymmetric unit, demonstrates that when 2,2,2-tri­fluoro­ethanol is used as a solvent, its high capacity as a hydrogen-bond donor leads to formation of an alcohol solvate.