209. Zur Kenntnis des Kohlenstoffringes. (40. Mitteilung)). Über die Schmelzpunkte in der Reihe der Polymethylen‐Kohlenwasserstoffe von Cyclo‐propan bis Cyclo‐octadecan

Interplay of thermochemistry and Structural Chemistry, the journal (volume 17, 2006) and the discipline

“…Disentangling enthalpy and entropy (including symmetry effects) is a worthy endeavor. Similar strong dependence on the number of methylene groups on melting points of cycloalkanes has also been shown [194] and is a related challenge to explain.…”

A tandem denitration-deoxygenation of .alpha.-nitro ketones via (p-tolylsulfonyl)hydrazones with lithium aluminum hydride: a practical synthesis of (Z)-9-tricosene, the sex pheromone of the housefly (Musca domestica)

“…The organic layer was dried with Na2S04, the solvent was removed by distillation, and the crude product was purified by short chromatography, over silica gel, using n-pentane as eluent. (Z)-19-Nitro-9-tricosen-18-one (21). A mixture of 19 (6.65 g, 25 mmol) and 1-nitropentane (20) (2.92 g, 25 mmol) was mechanically stirred for 5 min and then cooled in an ice bath.…”

“…The solvent was removed under reduced pressure to afford the crude -nitro ketone 21 (8.57 g), which does not need purification. However, after chromatography (cyclohexane-ethyl acetate, 8:2) 8.1 g (857c) of the pure (Z)-19-nitro-9-tricosen-18-one (21) was obtained as an oil: IR (neat) v 1730 (CO), 1552 (N02); NMR b 0.9 (2t, 6 H, J = 6.8 Hz), 1.1-2.12 (m, 32 H), 2.55 (m, 2 H), 5.08-5.15 (m, 1 H, J = 4.7 Hz), 5.28-5.42 (m, 2 H). Anal.…”

The Chemistry of Eight-Membered Carbocycles.

“…Cyclooctane has been prepared many times by hydrogenation of various cyclic olefins as proof of the existence of the eight-membered ring. It was included in the studies made on homologous series of cyclic paraffins in terms of melting point (134), parachor and compressibility (124), infrared and Raman spectra (67, 80), and heats of combustion (135,146). Heats of combustion measurements of the series cyclopentane to cycloóctane (146) showed that cycloóctane is of about the same stability as cyclopentane and cycloheptane but 9.6 kcal./mole less stable than cyclohexane.…”