5,10-dibromo-3,12-dihydro-3,3,12,12-tetramethylindeno<1,2-a>indene | 230958-05-1

• 分子结构分类: 有机化合物 - 苯类化合物 - 茚和异茚
• 英文名称: 5,10-dibromo-3,12-dihydro-3,3,12,12-tetramethylindeno<1,2-a>indene
• 英文别名: 2,7-Dibromo-9,9,10,10-tetramethylindeno[1,2-a]indene
• CAS: 230958-05-1
• 化学式: C₂₀H₁₈Br₂
• 分子量: 418.171
• InChiKey: XJYRJNFIFHNHIN-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.6
• 重原子数：
  22
• 可旋转键数：
  0
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.3
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为反应物：
  描述：

  5,10-dibromo-3,12-dihydro-3,3,12,12-tetramethylindeno<1,2-a>indene 在 silver(II) oxide 、 叔丁基锂 作用下， 以 四氢呋喃 为溶剂， 反应 20.0h， 生成 5,10-di(tert-butylaminoxyl)-3,12-dihydro-3,3,12,12-tetramethylindeno<1,2-a>indene
  参考文献：
  名称：

  Structure−Property Relationships in Trimethylenemethane-Type Biradicals. 2. Synthesis and EPR Spectral Characterization of Dinitroxide Biradicals

  摘要：

  Several trimethylenemethane-type (TMM-type) dinitroxide biradicals have been prepared that differ in tert-butylaminoxylphenyl ring torsion angles by virtue of different steric demands of their "spin-protecting groups". In addition, the synthesis of a TMM-type dinitroxide having a planar pi-system is reported. The synthetic route employed for the planar TMM-type biradical is general and should therefore expand, the utility of TMM-type biradicals that are susceptible to bond torsions that attenuate exchange coupling. The compounds presented are designed to be effective to map out J-coupling/conformation space in TMM-type biradicals. EPR spectroscopic parameters (hfcc and D-values) were compared to determine if their values reflected differences in conformation in the series of biradicals. Interestingly, neither N- nor H-hfcc varied within our series of biradicals/monoradicals in a regular fashion, indicating that there is no apparent relationship between N- or H-hfcc and conformation (as judged by molecular mechanics calculations). However, D-values, estimated from relative intensities of Delta m(s) = 1 and Delta m(s) = 2 transitions, are consistent with a varied degree of delocalization in the dinitroxides: smaller D-values for biradicals having smaller aryl torsions (and greater delocalization), and larger D-values for dinitroxides having greater aryl torsions (and less delocalization). All the biradicals studied, except 5(..), exhibited linear Curie plots. The linear Curie plots are consistent with both triplet ground-states and singlet-triplet degeneracies. Interestingly, dinitroxide 6(..) exhibited a linear Curie plot, despite the lack of a pi-coupling fragment. Biradical 5(..), however, is a ground-state singlet; species with the triplet lying about 140 cal/mol above the singlet.

  DOI：

  10.1021/jo990061j
• 作为产物：
  描述：

  二(4-溴苯基)甲醇 在 N-溴代丁二酰亚胺(NBS) 、 氯化锆(IV) 、 potassium carbonate 、 过氧化苯甲酰 作用下， 以 四氯化碳 为溶剂， 反应 3.58h， 生成 5,10-dibromo-3,12-dihydro-3,3,12,12-tetramethylindeno<1,2-a>indene
  参考文献：
  名称：

  Structure−Property Relationships in Trimethylenemethane-Type Biradicals. 2. Synthesis and EPR Spectral Characterization of Dinitroxide Biradicals

  摘要：

  Several trimethylenemethane-type (TMM-type) dinitroxide biradicals have been prepared that differ in tert-butylaminoxylphenyl ring torsion angles by virtue of different steric demands of their "spin-protecting groups". In addition, the synthesis of a TMM-type dinitroxide having a planar pi-system is reported. The synthetic route employed for the planar TMM-type biradical is general and should therefore expand, the utility of TMM-type biradicals that are susceptible to bond torsions that attenuate exchange coupling. The compounds presented are designed to be effective to map out J-coupling/conformation space in TMM-type biradicals. EPR spectroscopic parameters (hfcc and D-values) were compared to determine if their values reflected differences in conformation in the series of biradicals. Interestingly, neither N- nor H-hfcc varied within our series of biradicals/monoradicals in a regular fashion, indicating that there is no apparent relationship between N- or H-hfcc and conformation (as judged by molecular mechanics calculations). However, D-values, estimated from relative intensities of Delta m(s) = 1 and Delta m(s) = 2 transitions, are consistent with a varied degree of delocalization in the dinitroxides: smaller D-values for biradicals having smaller aryl torsions (and greater delocalization), and larger D-values for dinitroxides having greater aryl torsions (and less delocalization). All the biradicals studied, except 5(..), exhibited linear Curie plots. The linear Curie plots are consistent with both triplet ground-states and singlet-triplet degeneracies. Interestingly, dinitroxide 6(..) exhibited a linear Curie plot, despite the lack of a pi-coupling fragment. Biradical 5(..), however, is a ground-state singlet; species with the triplet lying about 140 cal/mol above the singlet.

  DOI：

  10.1021/jo990061j