Darstellung enantiomerenreiner 3-Oxa-2,7-diazabicyclo[3.3.0]octane und ihre Umwandlung in andere bicyclische Ringsysteme/Preparation of Pure Enantiomeric 3-Oxa-2,7-diazabicyclo[3.3.0]octanes and their Conversion to Other Bicyclic Ring-Systems
作者:Hans Günter Aurich、Michael Soeberdt
DOI:10.1515/znb-1999-0117
日期:1999.1.1
methylhydroxylamine afforded nitrones 6 (Me- N(O)=CH-CHR1-N(CH2Ph)CH2-CH=CR2R3) which underwent an intramolecular 1,3-dipolar cycloaddition providing 3-oxa-2,7-diazabicyclo[3.3.0]octanes, e.g. (1R,5R,8S)-7-benzyl-2,8- dimethyl-3-oxa-2,7-diazabicyclo[3.3.0]octane 7a (R1 = Me, R2 = R3 = H) and (1R,4R,5R,8S)- 7-benzyl-2,8-dimethyl-4-phenyl-3-oxa-2,7-diazabicyclo[3.3.0]-octane 7b (R1 = Me, R2 = Ph, R3 = H).
纯对映体 (S)-N-苄基丙氨醇 (R1 = Me) 和 (S)-N-苄基缬氨醇 (R1 = i-Pr) 与 Br-CH2-CH = CR2R3 (R2 = R3 = H;R2 = Ph, R3 = H;R2 = R3 = Ph)。Swern 氧化,然后用甲基羟胺处理得到硝酮 6(Me-N(O)=CH-CHR1-N(CH2Ph)CH2-CH=CR2R3),其经过分子内 1,3-偶极环加成反应得到 3-oxa-2,7 -二氮杂双环[3.3.0]辛烷,例如(1R,5R,8S)-7-苄基-2,8-二甲基-3-氧杂-2,7-二氮杂双环[3.3.0]辛烷7a (R1 = Me, R2 = R3 = H) 和 (1R,4R,5R,8S)-7-苄基-2,8-二甲基-4-苯基-3-氧杂-2,7-二氮杂双环[3.3.0]-辛烷 7b (R1 =我,R2 = Ph,R3 = H)。7a 和 7b 的还原性开环