85963-67-3Relevant academic research and scientific papers
2,4-Dioxa-, 2,4,9-Trioxa-, 2,4-Dioxa-9-aza-, 2-Oxa-4,9-diaza-, and 2,4,9-Triazaadamantanes
Quast, Helmut,Berneth, Claus-Peter
, p. 1345 - 1363 (2007/10/02)
The reaction of the trihalides 7a, b with sodium cyanide in dimethylformamide afforded the cyclopropanedicarbonitrile 9 instead of of the tricarbonitrile 7c which had been designed as a precursor to 2,4,9-triazaadamantanes.Both the photolysis and thermolysis of the remarkably stable triazide 13c proceeded in an ill-defined way, producing unidentifiable products among which neither the triazaadamantane 6a nor hydrolysis products of the triimine 14 could be detected.The readily cyclizing triketone 3l was obtained from the reaction of the tricarbonyl chloride 3k with an excess of lithium dimethylcuprate followed by careful work-up.It proved to be the key to several novel heteroadamantanes: Thus, methoxide brought about an intramolecular aldol addition and cyclization of 3l to the 2,4-dioxaadamantane 15.An excess of liquid ammonia converted 3l into the 2,4-dioxa-9-azaadamantane 16a almost quantitatively.The same ring system (16b) was formed in the reaction of 3l with 12 mol of hydrazine hydrate.In contrast, the reaction of 3l with a very large excess of hydrazine hydrate afforded the 2-oxa-4,9-diazaadamantane 16c.Finally, 3l reacted with dry hydrazine in ethanol to yield the 2,4,9-triazaadamantane 16d.The structures of the new compounds were established by IR and NMR spectroscopy.Analysis of the complex 1H NMR multiplets of the methylene protons of 15 and 16a - c by LAOCOON III shows that they arise exclusively from W-couplings of 2 - 3 Hz and geminal couplings.
