Aziridination of cyclic dienes with enantiopure 3-acetoxyaminoquinazolin-4(3H)-ones
作者:Robert S. Atkinson、Christopher K. Meades
DOI:10.1039/b102592a
日期:——
Aziridination of cyclopentadiene and cyclohepta-1,3-diene with (S)-3-acetoxyamino-2-(3-hydroxy-2,2-dimethylpropyl)quinazolin-4(3H)-one 6 (Q1NHOAc) in the presence of titanium(IV) tert-butoxide in dichloromethane takes place highly diastereoselectively: X-ray structure determinations show that the preferred sense of diastereoselectivity in both cases is the same as that previously found for aziridination of butadiene with 6. Aziridination of cyclohexa-1,3-diene with 6 was less diastereoselective in dichloromethane solution but highly diastereoselective in acetonitrile: in this solvent two diastereoisomeric cis-4-(Q1-amino)cyclohexen-3-ols 27 and 28 were also obtained as by-products. The same two amino
alcohols were obtained by ring-opening of the aziridine with acid and were each converted into Q1-free oxazolidinones having optical rotations which were similar in magnitude but opposite in sign.
Reactions of oximes and diethylhydroxylamine with titanium alkoxides
作者:A. Singh、C. K. Sharma、A. K. Rai、V. D. Gupta、R. C. Mehrotra
DOI:10.1039/j19710002440
日期:——
Alkoxides of titanium react exothermally with oximes and diethylhydroxylamine to give complexes of the formula, Ti(OR)4–x(L)x[x= 1–4; R = Pri when LH = oxime; R = Et, Pri, and But when LH = Et2NOH]. Alcoholysis of some of these give the corresponding t-butoxy-derivatives. I.r. spectra have been recorded and molecular weights determined.
钛的醇盐与肟和二乙基羟胺放热反应,生成通式为Ti(OR)4– x(L)x [ x = 1-4的配合物;R =镨我当LH =肟; R =乙基,丙基我和Bu吨当LH =的Et 2 NOH]。其中一些醇解得到相应的叔丁氧基衍生物。Ir光谱已记录下来,分子量已确定。
A two-step method for preparing Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub>–graphene as an anode material for lithium-ion hybrid capacitors
作者:Nansheng Xu、Xianzhong Sun、Xiong Zhang、Kai Wang、Yanwei Ma
DOI:10.1039/c5ra20168c
日期:——
Li4Ti5O12–graphene anode was prepared by a two-step method and applied to a lithium-ion hybrid capacitor which could deliver an energy density of 6.6 W h kg−1 based on the total mass of the whole device.
通过两步法制备了Li4Ti5O12-石墨烯负极,并应用于锂离子混合电容器中,该电容器能够在整个装置的总质量基础上提供6.6 W h kg-1的能量密度。
Synthesis, structure, and high catalytic activity of cationic alkoxytitanium(IV) complexes in the Diels-Alder reaction
作者:Yukihiro Motoyama、Masako Tanaka、Koichi Mikami
DOI:10.1016/s0020-1693(97)05471-6
日期:1997.3
Abstract The cationic alkoxytitanium complexes, [(i-PrO)2Ti(OTf)2(i-PrOH)2] (1a), [(i-PrO)2Ti(bpy)(i-PrOH)2](OTf)2 (3a_and [(i-PrO)2Ti(bpy)(OTf)(i-PrOH)](OTf) (4a), are synthesized as highly effective catalysts for the Diels-Alderreaction of 1-acetoxy-1,3-butadiene with methacrolein. X-ray crystal analysis of the tert-butoxy derivative reveals the dinuclear, six-coordinated, and distorted octahedral