Luminescent tungsten(<scp>vi</scp>) complexes as photocatalysts for light-driven C–C and C–B bond formation reactions
作者:Daohong Yu、Wai-Pong To、Glenna So Ming Tong、Liang-Liang Wu、Kaai-Tung Chan、Lili Du、David Lee Phillips、Yungen Liu、Chi-Ming Che
DOI:10.1039/d0sc01340d
日期:——
gram-scale is described. This complex could catalyse photochemical organic transformation reactions including borylation of aryl halides, such as aryl chloride, reductive coupling of benzyl bromides for C–C bond formation, reductive coupling of phenacyl bromides, and decarboxylative coupling of redox-active esters of alkyl carboxylic acid with high product yields and broad functional group tolerance.
光催化在实际合成应用中的实现取决于开发可大规模制备的廉价光催化剂。本文描述了一种空气稳定、吸收可见光的光致发光钨 ( VI ) 配合物,可以方便地以克级制备。该配合物可催化光化学有机转化反应,包括芳基卤化物(如芳基氯)的硼化反应、苄基溴还原偶联以形成 C-C 键、苯酰溴的还原偶联以及烷基羧酸的氧化还原活性酯与高产率和广泛的官能团耐受性。
Development of Chiral Bis-hydrazone Ligands for the Enantioselective Cross-Coupling Reactions of Aryldimethylsilanolates
作者:Scott E. Denmark、Wen-Tau T. Chang、K. N. Houk、Peng Liu
DOI:10.1021/jo502388r
日期:2015.1.2
aryldimethylsilanolates and arylbromides result in biaryl products with the same configuration and similar enantioselectivities implying that reductive elimination is the stereodetermining step. The origin of stereoselectivity is rationalized through computational modeling of diarylpalldium(II) complex which occurs through a conrotatory motion for the two aryl groups undergoing C–C bondformation.
Explorations into the Potential of Chiral Sulfonium Reagents to Effect Asymmetric Halonium Additions to Isolated Alkenes
作者:Scott Snyder、Alexandria Brucks、Daniel Treitler、Shu-An Liu
DOI:10.1055/s-0033-1338865
日期:——
While methods for the racemic dihalogenation and halohydroxylation of alkenes have been known for decades, enantioselective variants of these processes remain elusive. Initial attempts were made to overcome this long-standing challenge by exploring the potential of chiral, crystalline, sulfur-derived halonium reagents to accomplish the asymmetric dichlorination and iodohydroxylation of 1,2-dihydronaphthalene. Asymmetric dichlorination of this substrate was achieved in 57% yield and 14% enantiomeric excess (ee), but asymmetric iodohydroxylation was much more successful, giving 67% yield and 63% ee. Thorough studies were made of these processes, including investigation of various chiral sulfide derivatives, their substrate scopes, and the reaction conditions.