3,8-Diaza-bicyclo[3.2.1]octane

A colorless fluid boiling 178-180° with piperazine-like smell, which quickly adsorbs carbon dioxide when exposed to air.^[2]

The ring-system of 3,8-Diaza-bicyclo[3.2.1]octane is at once related to piperazine and to nortropine, both progenitors of many compounds of physiological importance, synthesis of 3,8-Diaza-bicyclo[3.2.1]octane seemed likely to be rewarding.^[1]

From 3-bentyl-3,8-diazabicyclooctane[3.2.1] (V). A solution of 20 g of 3-benzyl-3,8-diazabicyclooctane [3.2.1] in 400 ml of absolute ethanol was hydrogenated in the presence of 10 g. of 10% palladium on charcoal in an autoclave at 60° and 40 atm. pressure. After 3 hr., heating was stopped and the solution allowed to cool to room temperature. Then the catalyst was filtered off, the alcohol removed at atmospheric pressure, and the concentrated solution was distilled; yield 8.8 g. of 3,8-Diaza-bicyclo[3.2.1]octane (80%) ; b.p. 176-178'. The product easily adsorbed carbon dioxide when exposed to air. A sample was distilled again and the fraction boiling at 78-80°/40 mm. was collected and immediately analyzed.^[2]

[1] SAMUEL W. BLACKMAN   RICHARD B. The Synthesis of 3,8-Diazabicyclo[3.2.1]octane and Some of Its N-Substituted Derivatives[J]. The Journal of Organic Chemistry, 1961, 26 8: 2750-2755. DOI:10.1021/jo01066a032.
[2] GIORGIO CIGNARELLA   EMILIO O  GIANGIACOMO NATHANSOHN. Bicyclic Homologs of Piperazine. II. Synthesis of 3,8-Diazabicyclo[3.2.1]octane. New Synthesis of 8-Methyl-3,8-diazabicyclo[3.2.1]octane[J]. The Journal of Organic Chemistry, 1961, 26 8: 2747-2750. DOI:10.1021/jo01066a031.