Supramolecular Architectures in 5,5′-Substituted Hydantoins: Crystal Structures and Hirshfeld Surface Analyses

A series of three 5,5'-substituted hydantoin derivatives (1-3) were synthesized, and their crystal structures were solved using single-crystal synchrotron/powder-crystal X-ray diffraction data with a detailed analysis oil Hirshfeld surfaces and fingerprint plots facilitating a comparison of intermolecular interactions in building different supramolecular architectures. A comparison of supramolecular assembly in the compounds with that in similar 5,5'-substituted hydantoins in the Cambridge Structural Database (CSD) has been presented. The crystal packing in compounds 1-3 containing complementary hydrogen bonding groups, i.e. the amino NH donors and carbonyl 0 acceptors, exhibits three types of supramolecular synthons. In the dipropyl substituted hydantoin (1), intermolecular N-H center dot center dot center dot O hydrogen bonds with only one carbonyl O atom acting as a double acceptor generate a one-dimensional C-1(1)(4)C-1(1)(4)[R-2(2)(8)] network propagating along the [100] direction, while in 3, a 5-spiro fused hydantoin, the cyclic R-2(2)(8) motifs self-organize through pairs of N-H center dot center dot center dot O hydrogen bonds to form a C-2(2)(9)[R-2(2)(8)][R-2(2)(8)] framework running along the [1-10] direction. The molecular assembly in 2. with a dibutyl substitution at the hydantoin C-5 position, produces R-4(4)(17) synthons, which are edge-fused to form two-dimensional molecular sheets in the (100) plane. The formation of a supramolecular architecture built with an R-4(4)(17) synthon is unprecedented among the substituted hydantoin structures in the CSD.