Benzobicyclo octene system

The observed interatomic distance from the center of the aromatic ring to the C2-oxygen atom (CR to C2-0 ranges from 3.53 to 3.76 ii, with a mean value of 3.68 A, The benzobicyclo[2.2.2]octene system gives a reasonably good CR to C2-0 distance (3.78 A). As might be expected, compounds VII and VIII, in which the oxygen atom is built into a somewhat strained structure, provide a much less accurate CR to C2-0 distance,... 

Synthesis. The synthesis of the amphetamine and methamphetamine derivatives in the benzobicyclo[2.2.2]-octene system has been described elsewhere (141 and references cited therein). To be able to study certain of the pharmacological aspects of these compounds, 3H-derivatives were prepared of NM-X and NM-N by reducing the N-formyl derivatives of the amphetamine analogs NH-X and NH-N with lithium aluminum tritiide (142). 

Evaluation of Some Bicyclic Systems as Conformationally-Defined Phenylethylamines. X-Ray Crystallography. Perhaps the ultimate test of the suitability of a chemical structure for preparing conformationally-defined analogs would be their ability to produce biological effects identical to those of the parent compound. Since this ideal is rarely achieved, and since a "wrong" conformer should be inactive, it is useful to have other criteria with which to evaluate these systems. The bicyclic molecules to be examined in the present study are compounds I-VIII (Figure 7), benzobicyclo[2.2.2]octenes, benzobicyclo [2.2.1]heptenes, and 1,2,3,4-tetrahydro-l,4-epoxynaphthalenes. A number of structural parameters... 

Building the C-2 oxygen atom into the bicyclo-[2.2.1] ring system seriously distorts x, the O-C-C-N dihedral angle. As shown in Figure 10, rhe benzobicyclo [2. 2. 2 ] octenes provide excellent values for (endo, 59° exo, 56°), but VII forms an 83° angle. 

CNDO/2 Calculations on Bicyclic Systems. Calculation of the energy differences between the exo-and endo-isomers in either the benzobicyclo[2.2.2]octene or benzobicyclo[2.2.l]heptene system (e.g., I, II,... 

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