Hirshfeld surface analysis of new phosphoramidates. Issue 3 (21st May 2013)

• Record Type: Journal Article
• Authors: Tarahhomi, Atekeh; Pourayoubi, Mehrdad; Golen, James A.; Zargaran, Poorya; Elahi, Behrouz; Rheingold, Arnold L.; Leyva Ramírez, Marco A.; Mancilla Percino, Teresa
• Is Part Of: Acta crystallographica. Volume 69:Issue 3(2013:Jun.)
• Page Start: 260
• Page End: 270
• Publication Date: 2013-05-21
• DOI: 10.1107/S2052519213009445
• Languages: English
• ISSNs: 2052-5206

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Hirshfeld surfaces and two‐dimensional fingerprint plots are used to visualize and analyze intermolecular interactions in six new phosphoramidate structures, [2, 6‐F<sub>2</sub>—C<sub>6</sub>H<sub>3</sub>C(O)NH]P(O)[<italic>X</italic>]<sub>2</sub> {<italic>X</italic> = N(C<sub>2</sub>H<sub>5</sub>)<sub>2</sub> (1), [<italic>X</italic>]<sub>2</sub> = NHCH<sub>2</sub>C(CH<sub>3</sub>)<sub>2</sub>CH<sub>2</sub>NH and with one CH<sub>3</sub>OH solvated molecule (2)}, [C<sub>6</sub>H<sub>5</sub>O]<sub>2</sub>P(O)<italic>Y</italic> [<italic>Y</italic> = NC<sub>4</sub>H<sub>8</sub>O (3), NHC<sub>6</sub>H<sub>4</sub>(3‐Br) (4)] and [<italic>Z</italic>]<sub>2</sub>P(O)OP(O)[<italic>Z</italic>]<sub>2</sub> [<italic>Z</italic> = N(CH<sub>3</sub>)(CH<sub>2</sub>C<sub>6</sub>H<sub>5</sub>) (5), NHC<sub>6</sub>H<sub>4</sub>(4‐CH<sub>3</sub>) (6)]. Study of the short intermolecular contacts in structures (1)–(6) by Hirshfeld surfaces demonstrate that the O atom of P=O is a better H‐atom acceptor than the O atom of C=O for (1) and (2), and also relative to the O atom of the C<sub>6</sub>H<sub>5</sub>O group for (3) and (4), and relative to the bridge O atom of the P(O)OP(O) segment for (5) and (6). The results confirm that the crystal packing is related to the kind of substituent linked to the P atom. Compounds (1), (2), (4) and (6), with characteristic N—H...O hydrogen bonds, show a pair of intense spikes (including the intermolecular H...O contacts) in the fingerprint plots, summarizing the major features of each structure in the related two‐dimensional plot. For (3) and (5), without any N—H unit, the two short spikes are observed for (3) but are absent for (5). The upper <italic>d</italic><sub>e</sub> and <italic>d</italic><sub>i</sub> values (distances to the Hirshfeld surfaces for the nearest atoms outside and inside) in the fingerprint plots are more compact in (3) than in (4), and in (5) than in (6), reflecting the more efficient packing in (3) and (5). The tertiary N atoms of (3) and (5) do not take part in any intermolecular contacts involving H atoms. Moreover, structures (3)–(6) show greater contribution from C...H contacts relative to O...H contacts. Finally, Hirshfeld surfaces and fingerprint plots are employed for a comparison of the two independent molecules in the asymmetric unit of (1) and also, for a comparison of (6), in the orthorhombic crystal system, with the previously reported monoclinic polymorph (Pourayoubi, Fadaei <italic>et al.</italic>, 2012).</p> </abstract>