Sterically Directed Functionalization of Aromatic C−H Bonds: Selective Borylation Ortho to Cyano Groups in Arenes and Heterocycles
作者:Ghayoor A. Chotana、Michael A. Rak、Milton R. Smith
DOI:10.1021/ja0428309
日期:2005.8.1
Ir-catalyzed borylations of 4-substituted benzonitriles are described. In contrast to electrophilic aromatic substitutions and directed ortho metalations, C-H activation/borylation enables functionalization at the 2-position, adjacent to the cyano group, when the 4-subsitutent is larger than cyano. When an excess of borane reagent is used, diborylation can be achieved with a single regioisomer being
描述了 4-取代苄腈的 Ir 催化硼化。与亲电芳香取代和定向邻位金属化相反,当 4-取代基大于氰基时,CH 活化/硼酸化能够在与氰基相邻的 2-位进行官能化。当使用过量的硼烷试剂时,在某些情况下可以通过形成单一区域异构体来实现二硼化。还报道了空间定向硼酸化扩展到氰基取代的五元和六元环杂环。
Process for producing cyano substituted arene boranes and compounds
申请人:Smith R. Milton
公开号:US20060281939A1
公开(公告)日:2006-12-14
A process for producing cyano substituted arene boranes is described. The compounds are useful intermediates to pharmaceutical compounds using the cyano group as a reactant.
描述了一种生产氰基取代芳基硼烷的方法。这些化合物是制备药用化合物的有用中间体,使用氰基作为反应物。
C–H Borylation Catalysts that Distinguish Between Similarly Sized Substituents Like Fluorine and Hydrogen
作者:Susanne L. Miller、Ghayoor A. Chotana、Jonathan A. Fritz、Buddhadeb Chattopadhyay、Robert E. Maleczka、Milton R. Smith
DOI:10.1021/acs.orglett.9b02299
日期:2019.8.16
By modifying ligand steric and electronic profiles it is possible to C–H borylate ortho or meta to substituents in aromatic and heteroaromatic compounds, where steric differences between accessible C–H sites are small. Dramatic effects on selectivities between reactions using B2pin2 or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (HBpin) are described for the first time. Judicious ligand and borane combinations