A Robust Thiourea Synthon for Crystal Engineering

• Published in: Crystal growth & design Vol. 10; no. 8; pp. 3757 - 3762
• Main Authors: Paisner, Kathryn, Zakharov, Lev N, Doxsee, Kenneth M
• Format: Journal Article
• Language: English
• Published: Washington,DC American Chemical Society 04-08-2010
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of crystal growth; physics of crystal growth; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Crystal growth; Crystal engineering; Piperazines; Sulfoxides; Thioureas; Intermolecular interaction; Hydrogen bonds; Solvate; Thiourea; Dimers; Interaction potentials; Intramolecular hydrogen bond; Intramolecular interaction; Crystal structure; Synthon
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/cg100589n

Crystallographic characterization of a series of bis-thiourea derivatives derived from N,N′-bis(3-aminopropyl)piperazine revealed a highly conserved intramolecular hydrogen bonding pattern, with intramolecular S(6) [or, in one case, S(8)] hydrogen bonding interactions between each heterocyclic nitrogen atom and one proton of the adjacent propylthioureido substituent. These intramolecular hydrogen-bonding interactions lend an overall spiral-like structure to the molecules, rather reminiscent of the form of a spiral galaxy. These monomeric units assemble into infinite chains via the formation of intermolecular R2 2(8) cyclic thiourea dimers, with the exception of a phenyl derivative, which crystallized as a monomeric bis(dimethyl sulfoxide) solvate. The S(6) intramolecular hydrogen bond motif was maintained in the phenylthioureido derivatives of both N-(3-aminopropyl)morpholine and 3,3′-diamino-N-methyl-dipropylamine. The robustness of the “spiral galaxy” motif and its apparent ability to direct intermolecular interactions suggest its potential utility as a useful new synthon for solid-state design.