The structure and the catalytic activity of diphenylboron cation in solution

二苯基硼阳离子的结构及其在溶液中的催化活性

• 批准号: 17550039
• 负责人: FUJIO Mizue
• 金额: $ 2.3万
• 依托单位: Kyushu University :
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17550039/
• 关键词: Boron Cation; B-11 NMR Chemical Shift; Lewis Acidity; ab initio Calculation; Lewis Acid Catalyst; B-11 NMR化学シフト

A novel boron cationic behavior of diphenylchloroborane has been investigated by utilyzing the Lewis acids in aprotic solvents at room temperature, by monitoring ^<11>B, ^<13>C, and ^<121>Sb NMR spectroscopy in-situ, and the cationic species was confirmed by a correlation between the calculated and the experimental ^<11>B NMR chemical shifts. The heterolysis of diphenylchloroborane by the strong Lewis acid (SbCI_5, GaCI_3, AIBr_3) in nitromethane gave the nitromethane solvated diphenylboronium ion stabilized by electron donating O-atom of two nitromethane molecules. The nitromethane coordinated complex-ion can be converted into MeCN or THF coordinated complex-ion by adding 2 equivalents of solvents, and finally to the pyridine complex-ion. These four-coordinate diphenylboronium ions have no Lewis acidity due to coordination of nucleophiles. The abstraction of chloride ion from diphenylchloroborane did not proceed in non- nucleophilic solvents nor with AICI_3 and BCl_3 even in nitrometh … More ane. Treatment of diphenylchloroborane with one equivalent of pyridine in dichloromethane afforded the corresponding 1:1 adduct that gave highly Lewis acidic tricoordinate diphenylborenium ion by abstraction of chloride ion with the strong Lewis acid. The tricoordinate diphenylborenium ion existed in an equilibrium with the nitrometane-coordinate sp^3 cation in nitromethane depending on the substituent in pyridine while that in dichloromethane exists solely as sp^2 diphenylborenium ion for 4-NMe_2 to H substituent. The experimental ^<11>B chemical shifts of all species were in good agreement with the ab initio calculation results at the level of GIAO-HF/6-311+G(2d, p)//B3LYP/6-31+G(d), and the optimized structures were compatible with the ^<11>B, ^<13>C and ^<121>Sb NMR spectroscopy. In conclusion, the sp diphenylborinium ion ([Ph_2B]^+) incipiently produced was stablized by the π back-bonding (B-O or B-N) from solvent(s) and/or pyridine(s) to positive boron atom and these boron cation species should have an appreciably long life to exist as sp^2([Ph_2B(Py)]^+) or sp^3 diphenylboron cation ([Ph_2B(Py)NO_2Me]^+, [Ph_2B(PY)_2]^+), and [Ph_2B(Solv)_2]^+). Less

利用刘易斯酸在非质子溶剂中的室温反应，通过原位监测~（<11>B）、~（13）<13>C和<121>~（13）Sb的NMR谱，研究了二苯基氯硼烷的硼阳离子行为，并通过计算的~（13）B NMR化学位移与实验值之间的相关性，证实了该硼阳离子物种<11>的存在.用强刘易斯酸（SbCl_5，GaCl_3，AlBr_3）在硝基甲烷中异解二苯基氯硼烷，得到了由两个硝基甲烷分子的供电子O原子稳定的硝基甲烷溶剂化的二苯基硼鎓离子。通过加入2当量的溶剂，硝基甲烷配位离子可转化为MeCN或THF配位离子，最后转化为吡啶配位离子。由于亲核试剂的配位作用，这些四配位的二苯基硼离子没有刘易斯酸性。在非亲核溶剂中，也不能从二苯基氯硼烷中萃取氯离子，用AlCl_3和BCl_3萃取氯离子，甚至在硝基甲烷中也不能 ...更多信息 安。二苯基氯硼烷与1当量的吡啶在二氯甲烷中反应得到相应的1：1加合物，该加合物通过用强刘易斯酸萃取氯离子而得到高刘易斯酸性的三配位二苯基硼鎓离子。在硝基甲烷中，三配位的二苯基硼鎓离子与硝基甲烷配位的sp^3阳离子处于平衡状态，这取决于吡啶中取代基的不同;而在二氯甲烷中，4-NMe_2取代到H时，三配位的二苯基硼鎓离子仅以sp^2形式存在。在<11>GIAO-HF/6-311+G（2d，p）//B3 LYP/6-31+G（d）水平上，所有物种的~（13）B化学位移与从头计算结果吻合较好，优化结构与~（13）B，~（13）C和~（13）<11><13><121>Sb NMR谱一致.总之，sp二苯基硼离子（[Ph_2B]^+）通过π背键稳定（B-O或B-N）从溶剂和/或吡啶转移到正硼原子，这些硼阳离子物种应该具有相当长的寿命才能以sp ^2形式存在（[Ph_2B（Py）]^+）或sp^3二苯基硼阳离子（[Ph_2B（Py）NO_2Me]^+、[Ph_2B（PY）_2]^+）和[Ph_2B（Solv）_2]^+）。少

项目成果

Aminolysis of Y-Substituted Phenyl X-Substituted Cinnamates and Benzoates : Effect of Modification of Nonleaving Group from Benzoyl to Cinnamoyl

Y-取代的苯基 X-取代的肉桂酸酯和苯甲酸酯的氨解：非离去基团从苯甲酰基到肉桂酰基的修饰效果

• 发表时间: 2007
• 期刊: J. Org. Chem. 72 (in press)
• 作者: D.Terakado;M.Takano;T.Oriyama;折山 剛(分担執筆);折山 剛;I.-H.Um et al.
• 通讯作者: I.-H.Um et al.

The β-Silicon Effect 2. Substituent Effects on the Solvolysis Rate of 1-Aryl-2-(aryldimethylsilyl)ethyl 3,5-Dinitrobenzoates

β-硅效应2.取代基对3,5-二硝基苯甲酸1-芳基-2-(芳基二甲基硅基)乙酯溶剂分解速率的影响

• 发表时间: 2006
• 期刊: Bull.Chem.Soc.Jpn. 79・7(in press)
• 作者: D.Terakado;M.Takano;T.Oriyama;折山 剛(分担執筆);折山 剛;I.-H.Um et al.;中田和秀等;I.-H.Um et al.;K.Nakata et al.;中田和秀等;M.Fujio et al.;I.-H.Um et al.;K.Nakata et al.;M.Fujio et al.;I.-H.Um et al.;M.Fujio et al.
• 通讯作者: M.Fujio et al.

環置換アニリニウムイオンの水中酸性度に及ぼす要因に関する理論的研究

水中环取代苯胺离子酸性影响因素的理论研究

• 发表时间: 2006
• 期刊: 法政大学自然科学センター紀要 3
• 作者: D.Terakado;M.Takano;T.Oriyama;折山 剛(分担執筆);折山 剛;I.-H.Um et al.;中田和秀等;I.-H.Um et al.;K.Nakata et al.;中田和秀等
• 通讯作者: 中田和秀等

Theoretical study of medium effect on the acidities of ring-substituted anilinium ions in water

介质对水中环取代苯胺离子酸度影响的理论研究

• 发表时间: 2006
• 期刊: SRC Annual Report, Hosei Univ. Vol.3
• 作者: D.Terakado;M.Takano;T.Oriyama;折山 剛(分担執筆);折山 剛;I.-H.Um et al.;中田和秀等;I.-H.Um et al.;K.Nakata et al.;中田和秀等;M.Fujio et al.;I.-H.Um et al.;K.Nakata et al.
• 通讯作者: K.Nakata et al.

A facile synthesis of fused spiroketal skeleton: 2,2′-spirobi(4-aryl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydrochroman)

• DOI: 10.1016/j.tetlet.2005.09.103
• 发表时间: 2005-11
• 期刊: Tetrahedron Letters
• 影响因子: 1.8
• 作者: M. Ahmed;Syeda Asghari Ahmed;M. Uddin;M. Rahman;U. Romman;M. Fujio;Y. Tsuda