Synthesis of <i>Z</i>-(Pinacolato)allylboron and <i>Z</i>-(Pinacolato)alkenylboron Compounds through Stereoselective Catalytic Cross-Metathesis
作者:Elizabeth T. Kiesewetter、Robert V. O’Brien、Elsie C. Yu、Simon J. Meek、Richard R. Schrock、Amir H. Hoveyda
DOI:10.1021/ja403188t
日期:2013.4.24
first examples of catalytic cross-metathesis (CM) reactions that furnish Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds are disclosed. Products are generated with high Z selectivity by the use of a W-based monoaryloxide pyrrolide (MAP) complex (up to 91% yield and >98:2 Z:E). The more sterically demanding Z-alkenylboron species are obtained in the presence of Mo-based MAP complexes
公开了提供Z-(频哪醇)烯基硼和Z-(频哪醇)烯基硼化合物的催化交叉复分解(CM)反应的第一实例。通过使用 W 基单芳氧基吡咯 (MAP) 络合物,生成具有高 Z 选择性的产品(产率高达 91%,Z:E >98:2)。在 Mo 基 MAP 配合物存在下,可以获得空间要求更高的 Z-烯基硼物质,产率高达 93%,Z 选择性高达 97%。首次报道了 1,3-二烯和芳基烯烃的 Z 选择性 CM。该方法与催化交叉偶联相结合的实用性通过抗癌剂考布他汀 A-4 的简洁和立体选择性合成得到了证明。
Selective Hydrosilylation and Hydroboration of Allenes Catalyzed by Cobalt‐Pincer Complexes
作者:Dariusz Lewandowski、Grzegorz Hreczycho
DOI:10.1002/adsc.202400309
日期:——
regioselectivity and stereoselectivity in the hydroelementation of terminalallenes presents a formidable challenge. Despite the existence of various catalytic methods for their functionalization, this entire class of reactions remains significantly underdeveloped and demands extensive research. Here, we report a method for the hydroelementation of allenes using inexpensive PN5P pincer cobalt complexes built on