Strained Small Ring Compounds: Bridgehead Substituted Bicyclo [2.1.1]hexanes

Synthesis, Structure, and Conformational Dynamics of Bridgehead-Substituted Nitrosamines. Di-1-adamantylnitrosamine and Di-1-norbornylnitrosamine

“…Deviation from planarity at the amino nitrogen is negligible for 1 and 4 , very slight for 2 , and slight for 5 . We speculate that increased effective electronegativity of the 1-norbornyl bridgehead group may account for the slightly nonplanar amino nitrogen of 2 and that ring strain associated with having an sp 2 center in a six-membered ring accounts for the slight pyramidalization in 5 . It appears that large alkyl substituents in R 2 NNO do not result in significant deconjugation (twisting) of the NNO π system .…”

Adamantane: Consequences of the Diamondoid Structure

“…Again the "strangeness" of adamantanes is evident (Table V). The moments calculated from the refraction at the sodium D-line (P" -Ed) in the usual manner are considerably larger than any ob- served for acyclic or alicyclic halides: e.g., /-butyl chloride, µ = 2.13 D.; l-chlorobicyclo [2.2.1 Jheptane, µ = 2.17 D. (144); cyclohexyl bromide, µ = 2.2 D. If an estimated value for the total induced polarization, including an atomic polarization term (137,138) is used in the calculations (Pm -Pe+a), the moments have the expected values (Table V). Why these compounds should display an unusually high atomic polarization is not known at present.…”

Methylenecyclohexenes: inversion barriers from the far-infrared spectra

“…With the preferred procedure 3-cyclohexen-1-methyltosylate was refluxed with LiBr in acetone (7) giving the desired bromide in 74% yield (bp 72"C/12 Torr, lit. (6) bp 100-12O0Cj35 Torr).…”