Herein we present the development of asymmetric deacylative allylation of ketone enolates. The reaction directly couples readily available ketone pronucleophiles with allylic alcohols using facile retro-Claisen cleavage to form reactive intermediates in situ. The simplicity and robustness of the reaction conditions is demonstrated by the preparation of >6 g of an allylated tetralone from commercially available materials. Furthermore, use of nonracemic PHOX ligands allows intermolecular formation of quaternary stereocenters directly from allylic alcohols.
Regio- and Enantioselective Pd-Catalyzed Allylic Alkylation of Ketones through Allyl Enol Carbonates
作者:Barry M. Trost、Jiayi Xu
DOI:10.1021/ja043472c
日期:2005.3.9
ketones occurs asymmetrically in the presence of chiral ligands previously developed in this group. With 2-methylcyclohexanone, asymmetric regioselective alkylation occurs at the more substituted carbon without complications of polyalkylation. Alkylation to create quaternary centers in indanones and benzonabenone occurs in much higher ee than using tin or lithiumenolates. The sense of enantioinduction in
在该组先前开发的手性配体存在下,Pd 催化的烯醇烯丙基碳酸酯重组为烯丙基化酮是不对称的。使用 2-甲基环己酮,不对称区域选择性烷基化发生在更多取代的碳上,而没有多烷基化的并发症。在茚满酮和苯并苯酮中产生四元中心的烷基化发生的 ee 比使用锡或烯醇锂高得多。四氢萘酮中的对映诱导意义与烯醇化锡和锂的例子相反。第一次,在高 ee (78-99%) 的情况下,第三中心的不对称创建发生了。该反应与使用锂或烯醇锡之间的不同结果表明可能涉及不同的机制。
Development of Asymmetric Deacylative Allylation
作者:Alexander J. Grenning、Christie K. Van Allen、Tapan Maji、Simon B. Lang、Jon A. Tunge
DOI:10.1021/jo400793a
日期:2013.7.19
Herein we present the development of asymmetric deacylative allylation of ketone enolates. The reaction directly couples readily available ketone pronucleophiles with allylic alcohols using facile retro-Claisen cleavage to form reactive intermediates in situ. The simplicity and robustness of the reaction conditions is demonstrated by the preparation of >6 g of an allylated tetralone from commercially available materials. Furthermore, use of nonracemic PHOX ligands allows intermolecular formation of quaternary stereocenters directly from allylic alcohols.
Oxidation of Hindered Allylic C–H Bonds with Applications to the Functionalization of Complex Molecules
作者:Zachary C. Litman、Ankit Sharma、John F. Hartwig
DOI:10.1021/acscatal.6b03648
日期:2017.3.3
oxidation of hindered alkenes to form linear allylic esters. The combination of palladium(II) benzoate, 4,5-diazafluoren-9-one, and benzoquinone catalyzes the mild oxidation of terminalalkenes with tert-butyl benzoyl peroxide as an oxidant in the presence of diverse functional groups. Selective oxidation of terminalalkenes in the presence of trisubstituted and disubstituted alkenes has been achieved