α-(N,N-dimethylthiocarbamoyl)-4-methoxybenzyl pentafluorobenzoate

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: α-(N,N-dimethylthiocarbamoyl)-4-methoxybenzyl pentafluorobenzoate
• 英文别名: [2-(Dimethylamino)-1-(4-methoxyphenyl)-2-sulfanylideneethyl] 2,3,4,5,6-pentafluorobenzoate
• 化学式: C₁₈H₁₄F₅NO₃S
• 分子量: 419.372
• InChiKey: BIZZEIUTZWFALR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.1
• 重原子数：
  28
• 可旋转键数：
  6
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.22
• 拓扑面积：
  70.9
• 氢给体数：
  0
• 氢受体数：
  9

反应信息

• 作为反应物：
  描述：

  α-(N,N-dimethylthiocarbamoyl)-4-methoxybenzyl pentafluorobenzoate 以 水 、 乙腈 为溶剂， 生成 N,N-dimethyl-2-anisylthioacetamide-2-yl cation
  参考文献：
  名称：

  Remarkable kinetic stability of α-thiocarbamoyl substituted 4-methoxybenzylcations

  摘要：

  在用五氟苯酸酯或4-甲氧基苯甲酸酯的离去基团辐射前体时，产生了带有α-(N,N-二甲基氨基甲酰基)和α-(N,N-二甲基硫代氨基甲酰基)取代基的对甲氧基苯基甲基离子。这些离子在40:60乙腈:水和50:50甲醇:水中通过闪光光解被观察到，并且在溶剂中自行衰减和被偶氮离子捕获的速率常数被测量。在40%乙腈中研究的离子及其寿命为6，ArC+H-CONMe2，0.6微秒；2，ArC+H-CSNMe2，7毫秒；和4，ArC+(CH3)-CSMe2，6毫秒，其中Ar = 4-MeOC6H4。离子4通过从α-甲基基团中消除质子与溶剂反应，溶剂加成的速率常数必须小于1 s-1。CSNMe2取代的离子比硫酰胺基团被α-甲基替换的类似物寿命长10^5-10^7倍。这两种离子的紫外可见吸收光谱也与典型的4-甲氧基苯基甲基离子的光谱有显着差异。因此，寿命和光谱都指向苯甲基中心与硫酰胺基团之间的强相互作用。关键词：闪光光解、硫代氨基甲酰基稳定的离子、光溶解。

  DOI：

  10.1139/v98-225

文献信息

• How Does Organic Structure Determine Organic Reactivity? Nucleophilic Substitution and Alkene-Forming Elimination Reactions of α-Carbonyl and α-Thiocarbonyl Substituted Benzyl Derivatives
  作者：John P. Richard、Shrong-Shi Lin、Jeanne M. Buccigross、Tina L. Amyes

  DOI：10.1021/ja9629064

  日期：1996.1.1

  The effect of α-(N,N-dimethylcarbamoyl) and α-(N,N-dimethylthiocarbamoyl) substituents on the rate constants for partitioning of α-substituted 1-(4-methoxyphenyl)ethyl carbocations between nucleophilic addition of 50:50 (v:v) MeOH/H2O (ks, s-1) and deprotonation by this solvent (ke, s-1) have been investigated. The data show that these α-amide and α-thioamide substituents result in 80-fold and ≥30 000-fold

  α-(N,N-二甲基氨基甲酰基)和α-(N,N-二甲基硫代氨基甲酰基)取代基对α-取代的1-(4-甲氧基苯基)乙基碳正离子在50:50亲核加成之间分配速率常数的影响( v:v) MeOH/H2O (ks, s-1) 和该溶剂的去质子化 (ke, s-1) 已被研究。数据显示，这些 α-酰胺和 α-硫代酰胺取代基分别导致溶剂捕获 4-甲氧基苄基碳正离子的 ks 减少 80 倍和≥30 000 倍，但它们导致的变化要小得多。 ke用于通过溶剂使相应的α-取代的1-（4-甲氧基苯基）乙基碳正离子去质子化。因此，α-硫代酰胺取代基对 α-取代的 1-苯乙基碳正离子在溶剂分解和消除产物的形成之间分配的巨大影响主要是由于该 α-取代基对溶剂捕获碳正离子的 ks 的影响. 实验和计算研究的结果与共同...
• Solvent Effects on Carbocation−Nucleophile Combination Reactions:  A Comparison of π-Nucleophilicity in Aqueous and Organic Solvents
  作者：John P. Richard、Paul Szymanski、Kathleen B. Williams

  DOI：10.1021/ja981842p

  日期：1998.10.1

  M). These results show that only π-nucleophiles with Mayr nucleophilicity parameters greater than N ≈ 6 are sufficiently reactive to compete with nucleophilic aqueous solvents for addition to 1+, and they provide support for a simple relationship between the Ritchie N+ scale of nucleophilicity in water and the Mayr N scale of nucleophilicity in weakly polar nonnucleophilic solvents.2,3 Our data require

  α-(N,N-二甲基硫代氨基甲酰基)-4-甲氧基苄基碳阳离子 1+ 在 π-亲核试剂的亲核加成和 50:50 (v:v) 乙腈/水的溶剂 25° 之间分配的选择性报告如下C（亲核试剂，kNu/ks）：吡咯，23 M-1；2-甲氧基噻吩，≈2 M-1。从该碳正离子在含有以下碳亲核试剂的相同溶剂中的反应中未检测到亲核试剂加合物（<总产物的 2%）：噻吩 (0.10 M)、呋喃 (0.10 M)、乙基 1-丙烯基醚 (0.10 M) , 和 1-环己烯基三甲基甲硅烷基醚 (0.01 M)。这些结果表明，只有 Mayr 亲核性参数大于 N ≈ 6 的 π-亲核试剂具有足够的反应性，可以与亲核水性溶剂竞争添加到 1+，
• Relative Reactivities of a Strongly Nucleophilic Alkene and Azide Ion in Aqueous Methanol
  作者：John P. Richard、Shrong-Shi Lin、Kathleen B. Williams

  DOI：10.1021/jo961317d

  日期：1996.1.1
• Kinetic mechanism for dimerization of an α-thioamide substituted benzyl carbocation in aqueous solution
  作者：Kathleen B. Williams、John P. Richard

  DOI：10.1002/(sici)1099-1395(1998100)11:10<701::aid-poc26>3.0.co;2-4

  日期：——

  The products of reaction of the alpha-(N,N-dimethylthiocarbamoyl)-4-methoxybenzyl carbocation (If) intermediate of solvolysis of alpha-(N,N-dimethylthiocarbamoyl)-4-methoxybenzyl benzoate esters (1-O2CAr) show a strong dependence on solvent. The only product from reaction in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) is 2-dimethylamino-6-methoxybenzothiophene (2) from intramolecular cyclization of 1(+). The reaction of 1(+) in 50:50 (v/v) methanol-water (I = 0.50, NaClO4) gives mainly the adducts to solvent. In 50:50 (v/v) trifluoroethanol-water (I = 0.50, NaClO4), 1(+) partitions between reaction with solvent (k(s), 27% yield), cyclization to form 2 (k(s), 3% yield) and nucleophilic addition of 2 to 1(+) (k(alk), 70% yield) to form dimeric product 3, The yield of 3 in 50:50 (v/v) trifluoroethanol-water (I = 0.50, NaClO4) is independent of the leaving group at 1-O2CAr and remains constant as the concentration of the substrate is increased fourfold. These data show that the rate-determining step for dimerization of 1-O2CAr is ionization of substrate to form 1(+) and that the products of the reaction are determined by the rate constant ratio for partitioning of 1(+) between addition of solvent and cyclization. The rate constant ratios determined for the partitioning of 1(+) in 50:50 (v/v) trifluoroethanol-water (I = 0.50, NaClO4) were k(s)/k(c) = 0.8 M-1 and k(alk)/k(s) = 540 000 M-1. (C) 1998 John Wiley & Sons, Ltd.
• Remarkable kinetic stability of α-thiocarbamoyl substituted 4-methoxybenzylcations
  作者：Robert A McClelland、Victoria E Licence、John P Richard、Kathleen B Williams、Shrong-Shi Lin

  DOI：10.1139/v98-225

  日期：1998.12.1

  4-Methoxybenzyl cations bearing α-(N,N-dimethylcarbamoyl) and α-(N,N-dimethylthiocarbamoyl) substituents have been generated photochemically upon irradiation of precursors with pentafluorobenzoate or 4-methoxybenzoate leaving groups. The ions have been observed with flash photolysis in 40:60 acetonitrile:water and in 50:50 methanol:water, and rate constants were measured for their decay in solvent alone and for their capture by azide ion. The cations so studied and their lifetimes in 40% acetonitrile are 6, ArC⁺H-CONMe₂, 0.6 μs; 2, ArC⁺H-CSNMe₂, 7 ms; and 4, ArC⁺(CH₃)-CSMe_2, 6 ms, where Ar = 4-MeOC₆H₄. The cation 4 reacts with solvent by elimination of a proton from the α-methyl group, and the rate constant for solvent addition must be less than 1 s^-1. The CSNMe₂ substituted cations are 10⁵-10⁷-fold longer lived than analogs where the thioamide group has been replaced with an α-methyl. The UV-visible absorption spectra of these two cations also show significant differences from those of typical 4-methoxybenzyl cations. Thus, both the lifetimes and spectra point to a strong interaction of the benzylic centre with the thioamide group. Key words: flash photolysis, thiocarbamoyl stabilized carbocation, photosolvolysis.

  在用五氟苯酸酯或4-甲氧基苯甲酸酯的离去基团辐射前体时，产生了带有α-(N,N-二甲基氨基甲酰基)和α-(N,N-二甲基硫代氨基甲酰基)取代基的对甲氧基苯基甲基离子。这些离子在40:60乙腈:水和50:50甲醇:水中通过闪光光解被观察到，并且在溶剂中自行衰减和被偶氮离子捕获的速率常数被测量。在40%乙腈中研究的离子及其寿命为6，ArC+H-CONMe2，0.6微秒；2，ArC+H-CSNMe2，7毫秒；和4，ArC+(CH3)-CSMe2，6毫秒，其中Ar = 4-MeOC6H4。离子4通过从α-甲基基团中消除质子与溶剂反应，溶剂加成的速率常数必须小于1 s-1。CSNMe2取代的离子比硫酰胺基团被α-甲基替换的类似物寿命长10^5-10^7倍。这两种离子的紫外可见吸收光谱也与典型的4-甲氧基苯基甲基离子的光谱有显着差异。因此，寿命和光谱都指向苯甲基中心与硫酰胺基团之间的强相互作用。关键词：闪光光解、硫代氨基甲酰基稳定的离子、光溶解。