Ru-DPEN配合物在苯乙酮不对称氢转移反应制备手性α-苯乙醇中的应用

合成一种新型钌-手性二胺三元配合物RuCl[p-cymene][R,R-DPEN](DPEN=1,2-二苯基乙二胺)。利用此配合物作为催化剂催化苯乙酮的不对称氢转移反应,考察反应温度、反应时间、溶剂异丙醇用量、n(苯乙酮)∶n(RuCl[p-cymene][R,R-DPEN])和碱浓度对苯乙酮不对称氢转移反应的转化率和ee值的影响。结果表明,在反应温度40℃、n(叔丁醇钾)∶n(RuCl[p-cymene][R,R-DPEN])=10.3∶1、n(苯乙酮)∶n(RuCl[p-cymene][R,R-DPEN])=23.7∶1和反应时间24 h条件下,配合物对苯乙酮不对称氢转移反应具有良好的催化性能和较好的对映选择性,苯乙酮不对称氢转移反应转化率达99.63%,ee值达31.04%。

Antioxidant activity and total phenolic and flavonoid content of the extract and chemical composition of the essential oil of Eremostachys laciniata collected from Zagros

Objective: To examine the chemical component of the essential oil of Eremostachys laciniata and evaluate antioxidant activity of the extract.Methods: The hydrodistillated essential oil was analyzed by gas chromatography-flame ionization detector and gas chromatography–mass spectrometry. Also, antioxidant activity, total phenolic and flavonoid content were determined by 2,2-diphenyl-1-picrylhydrazyl, Folin-Ciocalteu and colorimetric method, respectively.Results: The major components of the essential oil were p-cymene(21.64%), linalool(17.93%), and a-pinene(11.42%). Also, the extract obtained by methanol showed a good antioxidant activity. The same extract also exhibited high phenolic and flavonoid contents.Conclusions: These results indicate that Eremostachys laciniata can be used in dietary applications with a potential to reduce oxidative stress.

C2对称手性四氮配体的合成、结构及催化苯乙酮不对称氢转移反应研究

报道了4个C2对称手性四氮配体（2a-d）的合成及其催化苯乙酮的不对称转移氢化,催化反应具有较高的转化率（90%~98%）和适中的对映选择性（2%~60%）.用X-射线单晶衍射仪对配体2d{（R,R,S,S,S,S）-1,3-Di[4,5-diphenyl-1-（p-toluenesulfonyl）-2-imidazolidine]benzene}进行了结构表征,单斜晶系,手性空间群P1211,Z=2,a=10.4814（6）,b=9.4332（5）,c=21.8758（14）,V=2161.7（2）3,Mr=829.01,Dc=1.274g/cm3,F（000）=872,最终GOF=1.023,R=0.0518和wR=0.1096.

4-取代-2,4-二羰基丁酸酯的不对称转移氢化反应研究及应用

在(R,R)-RuCl(Fsdpen)(p-cymene)催化下进行了4-芳基-2,4-二羰基丁酸酯的不对称氢转移反应研究。考察了溶剂和温度对反应的影响;并以DMF为溶剂在0℃时进行了7种4-芳基-2,4-二羰基丁酸酯的不对称转移氢化(ATH)反应,得到高达85%产率和96%ee的反应产物;同时探索了(2R,4S)-α-羟基-γ-苯基-丁内酯的不对称合成。

Ruthenium catalyzed amination cyclization of 1,2,4-butanetriol with primary amines:A borrowing hydrogen strategy for 3-pyrrolidinol synthesis

A ruthenium based catalytic system([Ru(p-cymene)Cl2]2/XantPhos with substoichiometric Cs2CO3)has been established to effectively achieve the first direct amination cyclization of 1,2,4-butanetriol with primary aromatic amines.The product of this sustainable hydrogen autotransfer process is valuable Naryl-3-pyrrolidinol.