Synthesis of <i>c</i><i>yclo</i>-2,4,6-Triarsa-1,3,5-triazanes from <i>c</i><i>yclo</i>-2,4-Diarsa-1,3-diazanes Demonstrating the General Influence of Substituent Steric Strain on the Relative Stability of Pnictazane Oligomers
作者:Neil Burford、Jeff C. Landry、Michael J. Ferguson、Robert McDonald
DOI:10.1021/ic050532m
日期:2005.8.1
Dipp) have been transformed into the corresponding 2,4,6-trichloro-cyclo-2,4,6-triarsa-1,3,5-triazanes on reaction with GaCl(3) followed by 4-(dimethylamino)pyridine (DMAP). The nitrogen bound Dmp and Dipp substituents impose "medium" substituent steric strain on the heterocycles influencing the relative thermodynamic stability of potential oligomers in favor of the trimers. This ring expansion disproportionation
2,4-二氯-1,3-二芳基-环-2,4-二氮杂-1,3-二氮杂(芳基= 2,6-二甲基苯基Dmp或2,6-二异丙基苯基Dipp)已被转化为相应的2,4,6-trichloro-cyclo-2,4,6-triarsa-1,3,5-triazanes与GaCl(3),然后是4-(二甲基氨基)吡啶(DMAP)反应。氮结合的Dmp和Dipp取代基在杂环上施加“中等”取代基空间应变,影响潜在的低聚物的相对热力学稳定性,有利于三聚体。该环膨胀歧化反应通过氯离子的提取和中间体2,4-二氯-1,3,5-三(2,6-二异丙基苯基)-环-2,4-二氮杂-1,3,5-引发。已经分离并在结构上表征了三氮烷-6-四氯镓酸砷。随后与4-(二甲基氨基)吡啶(DMAP)的反应影响从没食子酸根阴离子释放氯离子,并在三聚体中随后形成共价As-Cl键。这些观察结果与磷衍生物的观察结果相似,证明了这种新的合成方法在环戊烷化学的发展和多样化方面的普遍适用性。