Molecular structure of the 1:1 inclusion complex of monensin A lithium salt with acetonitrile

✍ Scribed by Adam Huczyński; Małgorzata Ratajczak-Sitarz; Andrzej Katrusiak; Bogumil Brzezinski

• Book ID: 103837662
• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 593 KB
• Volume: 871
• Category: Article
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2006.07.046

✦ Synopsis

Crystal structure of the inclusion crystal of monensin A lithium salt with acetonitrile, Li(C 36 H 61 O 11 )AECH 3 CN, has been studied by Xray diffraction, FT-IR spectroscopy and PM5 semiempirical methods. Monensin A lithium salt:acetonitrile (1:1) complex is isostructural with the previously studied crystals of monensin A sodium salt:acetonitrile (1:1) complex. The crystal space group is P2 1 2 1 2 1 with a = 12.6937( 9), b = 16.7689(12), c = 18.4927( 12) and Z = 4. The LiAO bond lengths are between 2.022(5) and 2.633(5) A ˚. The oxygen atoms of the carboxylate group are involved in two intramolecular hydrogen bonds of different strength: O(11)AHAEAEAEO(1) of 2.582(2)A ånd O( 10)AHAEAEAEO(2) of 2.636(2) A ˚. These two hydrogen bonds bind two ends of the monensin molecule, which in this way forms a pseudo cyclic structure wrapped around the Li + cation. The IR spectrum of the crystal confirms the results obtained by the X-ray study and provides spectroscopic evidence for the formation of the inclusion complex. The calculated structure of the monensin A lithium salt and the structural parameters are comparable with those determined by X-rays.