RadicalcationDiels–Alderreactions by titanium dioxide (TiO2) photocatalysis in lithium perchlorate/nitromethane solution are described. TiO2 photocatalysis promotes reactions between electron-rich dienes and dienophiles, which would otherwise be difficult to accomplish due to electronic mismatching. The reactions are triggered by hole oxidation of the dienophile and are completed by the excited
Doubly Diastereoconvergent Preparation and Microsolvation-Controlled Properties of (<i>Z</i>)- and (<i>E</i>)-1′-Lithio-1′-(2,6-dimethylphenyl)propenes
作者:Rudolf Knorr、Claudia Behringer、Monika Knittl、Ulrich von Roman、Ernst Lattke
DOI:10.1021/jacs.6b11003
日期:2017.4.5
their mixtures. Thus, the preparation of configurationally pure (Z)-1'-lithio-1'-(2,6-dimethylphenyl)propene [(Z)-1] from any Z,E mixture of the corresponding bromoalkenes with n-butyllithium succeeded by means of a user-friendly (E)-1 → (Z)-1 configurational interconversion. The subsequent treatment of (Z)-1 with a minimum amount of THF afforded exclusively (E)-1 as the other diastereomeric product
B(C
<sub>6</sub>
F
<sub>5</sub>
)
<sub>3</sub>
‐Catalyzed
<i>E</i>
‐Selective Isomerization of Alkenes
作者:Betty A. Kustiana、Salma A. Elsherbeni、Thomas G. Linford‐Wood、Rebecca L. Melen、Matthew N. Grayson、Louis C. Morrill
DOI:10.1002/chem.202202454
日期:2022.11.11
report the B(C6F5)3-catalyzed E-selective isomerization of alkenes. The transition-metal-free method is applicable across a diverse array of readily accessible substrates, accessing a broad range of synthetically useful products containing versatile stereodefined internal alkenes. Synthetic and computational mechanistic studies indicate that the isomerization proceeds along competing 1,2-hydride shift
Move along !:在此,我们报道了 B(C 6 F 5 ) 3 -催化的E -烯烃选择性异构化。不含过渡金属的方法适用于各种易于获得的底物,可获得范围广泛的合成有用产品,其中包含多功能立体定义的内部烯烃。合成和计算机理研究表明,异构化沿着竞争性 1,2-氢化物转移和氢化物提取途径进行。