ISSN:
1600-5740
Quelle:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Thema:
Chemie und Pharmazie
,
Geologie und Paläontologie
,
Physik
Notizen:
The structure of N-methyl-2-pyrrolidone (NMP; 1-methyl-2-pyrrolidinone) was determined at 168 K. Crystal data: m.p. 249 K, monoclinic P21/c, a = 6.221 (3), b = 12.076 (2), c = 7.529 (4) Å, β = 111.03 (2)°, V = 527.9 (4) Å3, Z = 4, Dx = 1.247 Mg m−3, μ = 0.082 mm−1, R = 0.058 for 1190 unique reflections. It adopts a slightly puckered ring conformation in the solid state, which is intermediate between a twist and an envelope conformation. The N-methyl group takes part in two almost linear intermolecular C—H...O hydrogen bonds to neighbouring keto groups [d(H...O) = 2.57 (2)/ 2.65 (2) Å, d(C...O) = 3.552 (2)/3.482 (2) Å, angle (C—H...O) = 160 (1)/148 (2)°], which cause a notable deviation from its usually preferred conformation with one C—H bond being almost eclipsed to the adjacent N—C amide bond. These findings are substantiated by force-field and high-level ab initio calculations on isolated NMP molecules.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1107/S0108768196008300
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