TiCl4-promoted aldol condensations of S-4-chlorophenyl thioesters with enals or dienals led to the production of dienyl or trienyl thioesters in good yields. Due to good crystallinity, products with high E/Z ratios were obtained by simple filtration in many cases. Reduction of the thioester moiety by DIBAL-H afforded the corresponding unsaturated aldehydes while suppressing the E/Z-isomerization and
Ti-direct, powerful, stereoselective aldol-type additions of esters and thioesters to carbonyl compounds: application to the synthesis and evaluation of lactone analogs of jasmone perfumes
thiophenyl esters or thioaryl esters with aldehydes and ketones was performed (total 46 examples). The present method is advantageous from atom-economical and cost-effective viewpoints; good to excellent yields, moderate to good syn-selectivity, substrate variations, reagent availability, and simple procedures. Utilizing the present reaction as the key step, an efficient short synthesis of three lactone
Air-stable binuclear Titanium(IV) salophen perfluorobutanesulfonate with zinc power catalytic system and its application to C–S and C–Se bond formation
作者:Lingxiao Wang、Jie Qiao、Jiancong Wei、Zhiwu Liang、Xinhua Xu、Ningbo Li
DOI:10.1016/j.tet.2019.130750
日期:2020.1
An air-stable μ-oxo-bridged binuclear Lewisacid of titanium(IV) salophen perfluorooctanesulfonate [Ti(salophen)H2O}2O][OSO2C4F9]2 (1) was successfully synthesized by the reaction of TiIV(salophen)Cl2 with AgOSO2C4F9 and characterized by techniques such as IR, NMR and HRMS. This complex was stable open to air over a year, and exhibited good thermal stability and high solubility in polar organic solvents
通过反应成功合成了稳定的空气稳定的μ-氧桥双核路易斯酸钛(IV)Salophen全氟辛烷磺酸[Ti(salophen)H 2 O} 2 O] [OSO 2 C 4 F 9 ] 2(1)。AgOSO 2 C 4 F 9制备Ti IV(盐基)Cl 2并通过IR,NMR和HRMS等技术进行表征。该复合物可在一年中稳定地暴露于空气中,并具有良好的热稳定性和在极性有机溶剂中的高溶解度。该配合物还具有相对较强的酸度,强度为0.8
Flash vacuum pyrolysis of alkoxycarbonyl/sulfinyl stabilised phosphorus ylides: generation and intramolecular insertion of alkoxycarbonyl(sulfenyl)carbenes
作者:R. Alan Aitken、Martin J. Drysdale、Bruce M. Ryan
DOI:10.1039/c39940000805
日期:——
Flashvacuumpyrolysis of phosphorus ylides stabilised both by ester and sulfinyl groups results mainly in extrusion of Ph3PO to generate alkoxycarbonyl(sulfenyl)carbenes; these undergo intramolecular insertion into CH of the alkoxycarbonyl group giving β-lactones which under the conditions lose CO2 to afford alkenyl sulfides.