Synthesis and Reactions of 3- and 3,7-Substituted Bicyclo[3.3.1]nonanes

Abstract

The readily available e«do-7-aminomethylbicyclo[3.3.1]nonan-3-one serves as a convenient precursor for a variety of 3-and 3,7-substituted bicyclo[3.3.1]nonanes. The individual steps generally proceed in high yield.New compounds which are made available include endo-3-bicyclo[3.3.1] nonylmethylamine, iV,jV-dimethyl-7methylene-endo -3-bicyclo [3.3.1] nonylamine, 7-methylenebicyclo [3.3.1] non-2-ene, and endo-3-bicyclo [3.3.1]nonylcarbonitrile. l-Methyl-2-oxaadamantane was also prepared. In addition, novel routes are provided for the indicated substances, 3-methylenebicyclo [3.3.1] nonane, endo-3-methylbicyclo [3.3.1] nonane, 3-methylbicyclo- [3.3.1] non-2-ene, and 3-bicyclo[3.3.l]nonylcarboxylic acid.Various methods have been employed for the preparation of bicyclo [3.3.1 [nonanes, in which acyclic or monocyclic materials serve as the immediate precrusors.2 Included in some of the newer approaches is the ring opening of suitably substituted adamantanes, which generally leads to 3,7-disubstituted derivatives.2•3 Recently, in this category, l-V,V-dichloroaminoadamantane was found4 to provide endo-7-aminomethylbicyclo[3.3.1]nonan-3-one (1) in good yield from rearrangement by aluminum chloride with subsequent

Versatile intermediates for heteroatom-substituted adamantane derivatives

“…The refluxing of the bicyclic diene with formic acid provided another possible route. 20 The number of side products, somewhat more plentiful than expected, made this an unacceptable procedure.…”

“…Refluxing was continued for 18 h with sporadic magnetic stirring due to the fact that the brittle salt intermediate adhered to the bottom of the flask quite tenaciously. After cooling, the supernatant liquid was decanted, the residue was thoroughly washed four times with reagent grade dry benzene, and the solvent was removed under reduced pressure (20 Torr and then 0.2 Torr). Hydrolysis of the residue was accomplished by the addition of 1.11. of ice water and stirring was continued for 3.5 h at 0-2 °C.…”

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22) Opening at the less substituted carbon has been called the "normal" mode while opening at the more substituted carbon has been called the "abnormal" mode (cf. ref [18][19][20]. Since this terminology is backwards for carbocation reactions, its use here would be confusing.

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Adamantanes and related compounds. XII. Diazotization of endo-7-aminomethylbicyclo[3.3.1]nonan-3-ols and endo-7-aminomethylbicyclo[3.3.1]non-2-ene

“…In related studies,8 diazotization of 1 yielded 4-protoadamantanone and 3-methylbicyclo[3.3.1]non-2-en-7-one (5). endo-3-Aminomethylbicyclo[3.3.1] nonane (6)…”