Reported is a novel palladium(II)‐initiated Catellani‐type reaction that utilizes widely accessible aryl boronic acids as the substrates instead of aryl halides, thereby greatly expanding the existing scope of this powerful transformation. This borono‐Catellani reaction was promoted by cooperative catalysis between Pd(OAc)2 and the inexpensive 5‐norbornene‐2‐carbonitrile. Practicality is the striking
A metal‐free radical borylation of alkyl and aryl iodides with bis(catecholato)diboron (B2cat2) as the boron source under mild conditions is introduced. The borylation reaction is operationally easy to conduct and shows high functional group tolerance and broad substrate scope. Radical clock experiments and density functional theory calculations provide insights into the mechanism and rate constants
介绍了在温和条件下以双(儿茶酚)二硼(B 2 cat 2 )作为硼源对烷基碘化物和芳基碘化物进行金属自由基硼化反应。硼化反应操作简便,具有较高的官能团耐受性和广泛的底物范围。自由基时钟实验和密度泛函理论计算提供了对 B 2 cat 2的 C 自由基硼化的机制和速率常数的见解。
Catalytic Synthesis of Atropisomeric <i>o</i>-Terphenyls with 1,2-Diaxes via Axial-to-Axial Diastereoinduction
and convergent strategy for the assembly of atropisomeric o-terphenyls with 1,2-diaxes via palladium/chiral norbornene cooperative catalysis and axial-to-axial diastereoinduction. Readily available aryl iodides, 2,6-substituted aryl bromides, and potassium aryl trifluoroborates are used as the building blocks, laying the foundation for diversity-orientedsynthesis of these scaffolds (46 examples).
Palladium-Catalyzed Alkyne Insertion/Suzuki Reaction of Alkyl Iodides
作者:Brendan M. Monks、Silas P. Cook
DOI:10.1021/ja307761f
日期:2012.9.19
A palladium-catalyzed alkyne insertion/Suzuki reaction with unactivated alkyliodides is described. Under the reaction conditions, selective migratory insertion of alkynes avoids β-hydride elimination and provides a facile synthesis of stereodefined, tetrasubstituted olefins. The transformation offers broad substrate scope for both the alkyliodide and boron nucleophile. Mechanistic studies have revealed