1-(4-methoxyphenyl)-2,2-diphenylethynyl cation | 86996-37-4

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 二苯乙烯类
• 英文名称: 1-(4-methoxyphenyl)-2,2-diphenylethynyl cation
• 英文别名: 1-p-methoxyphenyl-2,2-diphenylvinyl cation；1-(4-methoxyphenyl)-2,2-diphenylvinyl cation；1-(2,2-Diphenylethenyl)-4-methoxybenzene
• CAS: 86996-37-4
• 化学式: C₂₁H₁₇O
• 分子量: 285.365
• InChiKey: LKWAFVBWGFXLJP-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6
• 重原子数：
  22
• 可旋转键数：
  4
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.05
• 拓扑面积：
  9.2
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  2,2,2-三氟乙醇 、 1-(4-methoxyphenyl)-2,2-diphenylethynyl cation 生成 1-p-Methoxyphenyl-2,2-diphenylvinyl-2,2,2-trifluorethylether
  参考文献：
  名称：

  为什么乙烯基阳离子是缓慢的亲电试剂？

  摘要：

  乙烯基阳离子 2 [Ph2C=C+-(4-MeO-C6H4)] 和 3 [Me2C=C+-(4-MeO-C6H4)]（由激光闪光光解产生）与多种亲核试剂（例如、吡咯、卤化物离子和含有不同量水或醇的溶剂）已通过光度法测定。发现亲核试剂对这些乙烯基阳离子的反应顺序与对二芳基碳鎓离子（二苯甲基鎓离子）的反应顺序相同。然而，乙烯基阳离子的反应速率受亲核试剂变化的影响仅是二苯甲基离子的反应速率的一半。因此，乙烯基阳离子和二苯甲基离子的相对反应性在很大程度上取决于亲核试剂的性质。结果表明，乙烯基阳离子 2 和 3 分别反应，使用三氟乙醇比母体二苯鎓离子 (Ph)2CH+ 慢 227 和 14 倍，即使在溶剂分解反应（25°C 时为 80% 乙醇水溶液）中，导致 2 和 3 的乙烯基溴离子化得更慢（半衰期 1.15年和 33 天）比 (Ph)2CH-Br（半衰期 23 秒）。通过高级 MO 计算研究了这

  DOI：

  10.1021/jacs.6b10889
• 作为产物：
  描述：

  1-(1,2-Diphenylethenyl)-4-methoxybenzene 以 乙腈 为溶剂， 生成 1-(4-methoxyphenyl)-2,2-diphenylethynyl cation
  参考文献：
  名称：

  KINETIC STUDIES ON β-ARYL MIGRATION ACROSS THE DOUBLE BOND IN VINYL CATIONS

  摘要：

  通过在乙腈中对相应的溴化乙烯基进行激光闪烁光解，测定了乙烯基阳离子中 β-芳基迁移的速率。Ph(An)C=\overset+C-Ph→An-\overset+C=CPh2 中的β-苯基迁移过程相对缓慢（273 K 时 k=7.4 × 106 s-1）。

  DOI：

  10.1246/cl.1984.2101

文献信息

• Lifetimes and UV-visible absorption spectra of benzyl, phenethyl, and cumyl carbocations and corresponding vinyl cations. A laser flash photolysis study
  作者：Frances L Cozens、V M Kanagasabapathy、Robert A McClelland、Steen Steenken

  DOI：10.1139/v99-210

  日期：1999.12.5

  Benzyl (4-MeO, 4-Me, and 4-methoxy-1-naphthylmethyl), phenethyl (4-Me₂N, 4-MeO, 3,4-(MeO)₂, 4-Me, 3-Me, 4-F, 3-MeO, 2,6-Me₂, parent, and 4-methoxy-1-naphthylethyl) and cumyl (4-Me₂N, 4-MeO, 4-Me, parent) cations have been studied by laser flash photolysis (LFP) in 2,2,2-trifluoroethanol (TFE) and 1,1,1,3,3,3-hexafluoroisopropanol (HFIP). In most cases styrene or α-methylstyrene precursors were employed for the phenethyl and cumyl ions, the intermediate being obtained by solvent protonation of the excited state. Benzyl cations were generated by photoheterolysis of trimethylammonium and chloride precursors. While a 4-MeO substituent provides sufficient stabilization to permit observation of cations in TFE, cations with less stabilizing substituents usually require the less nucleophilic HFIP. Even in this solvent, the parent benzyl cation is too short-lived (lifetime <20 ns) to be observed. When generated in HFIP, phenethyl cations can be seen to react with unphotolyzed styrene, giving rise to dimer cations that are observed to grow in as the initial phenethyl cation decays. The dimer cations, in common with the oligomer cations seen in cationic styrene polymerization, have a λ_max 15-20 nm higher than the monomer and react with both solvent and styrene several orders of magnitude more slowly. This stabilization relative to the phenethyl may reflect an interaction with the aryl group present at the gamma-carbon. Cations 4-MeOC₆H₄C⁺(R)-CH₃ (R = Me, Et, i-Pr, t-Bu, cyclopropyl, C₆H₅, 4-MeOC₆H₄) were generated in TFE via the photoprotonation route. The alkyl series shows that steric effects are important in the decay reaction. The cation with R = cyclopropyl is a factor of 1.5 less reactive than the cation where R = phenyl. Several vinyl cations have also been generated by photoprotonation of phenylacetylenes. ArC⁺=CH₂ has a reactivity very similar to that of its analog ArC⁺H-CH₃, the vinyl cation being slightly (factors of 2-5) shorter-lived. For the various series of cations, including vinyl, substituents in the aryl ring have a consistent effect on the λ_max, a shift to higher wavelength relative to hydrogen of 15 nm for 4-Me, 30 nm for 4-MeO, and 50 nm for 4-Me₂N.Key words: photogenerated carbocations, carbocation lifetime, styrene, photoprotonation.

  苯甲基（4-MeO，4-Me和4-甲氧基-1-萘基甲基）、苯乙基（4-Me2N，4-MeO，3,4-(MeO)2，4-Me，3-Me，4-F，3-MeO，2,6-Me2，母体和4-甲氧基-1-萘基乙基）和叔丁基（4-Me2N，4-MeO，4-Me，母体）阳离子在2,2,2-三氟乙醇（TFE）和1,1,1,3,3,3-六氟异丙醇（HFIP）中通过激光闪光光解（LFP）进行了研究。在大多数情况下，苯乙烯或α-甲基苯乙烯前体被用于苯乙基和叔丁基离子，中间体通过溶剂质子化激发态而获得。苯甲基阳离子是通过三甲基铵和氯化物前体的光异裂生成的。虽然4-MeO取代基提供了足够的稳定性以在TFE中观察到阳离子，但具有较少稳定取代基的阳离子通常需要较不亲核的HFIP。即使在这种溶剂中，母体苯甲基阳离子也太短寿命（寿命<20 ns）而无法观察到。在HFIP中生成的苯乙基阳离子可以看到与未经光解的苯乙烯反应，导致观察到的二聚体阳离子在初始苯乙基阳离子衰减时增长。与阳离子苯乙烯聚合中观察到的寡聚体阳离子一样，二聚体阳离子的λmax比单体高15-20 nm，并且与溶剂和苯乙烯反应速度慢几个数量级。相对于苯乙基的这种稳定性可能反映了与伽马碳上存在的芳基的相互作用。在TFE中通过光质子化途径生成了4-MeOC6H4C+(R)-CH3（R = Me，Et，i-Pr，t-Bu，环丙基，C6H5，4-MeOC6H4）阳离子。烷基系列表明立体效应在衰减反应中很重要。当R = 环丙基时，其反应性比R = 苯基的阳离子少1.5倍。还通过对苯乙炔的光质子化生成了几种乙烯阳离子。ArC+=CH2的反应性与其类似物ArC+H- 非常相似，乙烯阳离子寿命略短（2-5倍因子）。对于包括乙烯在内的各系列阳离子，芳香环中的取代基对λmax有一致的影响，相对于氢的15 nm的4-Me，30 nm的4-MeO和50 nm的4-Me2N的波长偏移。关键词：光产生的碳正离子，碳正离子寿命，苯乙烯，光质子化。
• Study of the Time-resolved IR Spectrum of α-Arylvinyl Cations Generated by Laser Flash Photolysis
  作者：Masashi Kotani、Shinjiro Kobayashi、Masaaki Mishima、Yuji Hori

  DOI：10.1246/cl.2003.294

  日期：2003.3

  The characteristic stretching band of the C(sp2)=C(sp)+ moiety in vinyl cations was observed for the first time around 1870 cm−1 by a time-resolved IR spectrometry with 266 nm or 308 nm laser flash irradiation of (4-methoxyphenyl)alkynes in TFE and α-arylvinyl bromide in acetonitrile. The ultraviolet-visible and the IR absorption maxima were affected by the β-substituents.

  用 266 nm 或 308 nm 激光闪烁照射 TFE 中的 (4-methoxyphenyl)alkynes 和乙腈中的α-芳基溴乙烯基，通过时间分辨红外光谱法首次观察到乙烯基阳离子中 C(sp2)=C(sp)+ 分子的特征伸展带在 1870 cm-1 附近。紫外-可见光和红外吸收最大值受 β-取代基的影响。
• Kobayashi, Shinjiro; Zhu, Qin Qin; Schnabel, Wolfram, Zeitschrift fur Naturforschung, B: Chemical Sciences, 1988, vol. 43, # 7, p. 825 - 829
  作者：Kobayashi, Shinjiro、Zhu, Qin Qin、Schnabel, Wolfram

  DOI：——

  日期：——
• Formation and Decay of an Aromatic Vinyl Cation in Supercritical CF₃H
  作者：Toshihiko Arita、Okitsugu Kajimoto

  DOI：10.1021/jp026988w

  日期：2003.3.1

  The effect of local density enhancement on the diffusion-controlled reactions in supercritical (SC) fluids has been clearly detected in the recombination reaction of a vinyl cation, 1-(4-methoxyphenyl)-2,2-diphenyl cation, with Br- in SC CF3H. With increasing density of SC CF3H, the observed recombination rate as a whole decreased rapidly in proportion to 1/etaepsilon, where eta and epsilon are the bulk viscosity and dielectric constant of the medium, respectively. Near the critical density, the rate constant was found to be much smaller than the predicted value from the 1/etaepsilon relation based on the Smolchowski-Debye scheme. This deviation indicates that the local density enhancement retards the recombination rate mainly due to the enhancement of dielectric constant.