NOVEL 9,9-DIOL SYSTEMS STARTING FROM A 3,7- DIAZABICYCLO[3.3.1]NONAN-9-ONE NUCLEUS-SINGLE CRYSTAL X-RAY DIFFRACTION ANALYSIS OF 3-(2-PROPYL)-7-BENZYL-3,7-DIAZABICY CL0[3.3.1]NONAN-9,9-DIOL HYDROBROMIDE, 3-(2-PROPY L)-7-[3,4-DIMETHOXYBENZYL)-3,7-DIAZABICY CLO[3.3.1]NONAN-9,9-DIOL HYDROBROMIDE, AND 3,7-DIISOPROPYL-3,7-DIAZABICY CLO[3.3.1]NONAN-9,9-DIOL DIHYDROCHLORIDE
作者:Sameer Tyagi、K. Darrell Berlin、M. Bilayet Hossain、Cindy Sinars、Dick Van Der Helm、Subbiah Sangiah
DOI:10.1080/10426509708044224
日期:1997.4.1
Attempts to make inorganic metal complexes of 3,7-diazabicyclo[3.3.1]nonan-9-ones and metal bromides in fresh, reagent-grade, undried THF generated rare 9,9-diols. Treatment of the ketones with anhydrous HBr(g) in anhydrous ether gave hydrobromides with the proton on nitrogen and with the carbonyl group Intact. The hydrobromides were extremely hygroscopic and exhibited a strong propensity to form the corresponding 9,9-diol system. The mechanism of formation of the diols is discussed as well as a rationale for the stability of such diols via H-bonding in the solid state. The X-ray diffraction analyses of 3-(2-propyl)-7-benzyl-3,7-diazabicyclo[3.3.1]nonan-9,9-diol hydrobromide, 3-(2-propyl)-7-(3,4-dimethoxybenzyl)-3,7-diazabicyclo[3.3.1]nonan-9,9-diol hydrobromide, and 3,7-diisopropyl-3,7-diazabicyclo[3.3.1]nonan-9,9-diol dihydrochloride revealed a proton on N(3) and all bicyclic systems as chair-chair conformations in the solid state. The dihydrochloride was, of course, also protonated on N(7). This is the first systematic study of this type of 9,9-diol of the 3,7-diazabicyclo[3.3.1]nonane system and the corresponding carbonyl-containing hydrobromides with the proton on a nitrogen atom [N(3)].