Palladium-Catalyzed Cross-Coupling of <i>gem</i>-Bis(boronates) with Aryl Halides: An Alternative To Access Quaternary α-Aryl Aldehydes
作者:Purui Zheng、Yujie Zhai、Xiaoming Zhao、Tao XU
DOI:10.1021/acs.orglett.8b03560
日期:2019.1.18
The compounds with a quaternary α-aryl aldehyde skeleton are important units in organic chemistry. Previously, the aryl group and carbonyl group are introduced in a stepwise manner. Herein, a novel route is developed to construct the quaternary α-aryl aldehydes with gem-bis(boronates) as precursors, in which the two groups are installed simultaneously. The gem-bis(boronates) are readily available from
)ethyl)-3-(trifluoromethyl)benzamide series of human CCR2 chemokine receptor antagonists was identified. With a pharmacophore model based on known CCR2 antagonists a new core scaffold was designed, analogues of it synthesized and structure–affinity relationship studies derived yielding a new high affinity CCR2 antagonist N-(2-((1-(4-(3-methoxyphenyl)cyclohexyl)piperidin-4-yl)amino)-2-oxoethyl)-3-(
bromides. The reaction proceeds efficiently when a combination of a highly substituted bromoalkene and a hydrazone derived from a ketone are employed, pointing to the convenience of a stericallyencumbered environment. This unprecedented process allows for the stereocontrolled preparation of highly substituted dienes and polyenes.
Olefination of Carbonyl Compounds through Reductive Coupling of Alkenylboronic Acids and Tosylhydrazones
作者:M. Carmen Pérez-Aguilar、Carlos Valdés
DOI:10.1002/anie.201200683
日期:2012.6.11
The partners decide: The CC bond‐forming reductive cross‐coupling of alkenylboronicacids and tosylhydrazones takes place under mild reaction conditions without the need of a metal catalyst, thus giving rise to olefination‐type products (see scheme). The position of the double bond in the product is determined by the structure of the coupling partners.
A palladium-catalyzed Barluenga cross-coupling – Reductive cyclization sequence to substituted indoles
作者:S.M. Ashikur Rahman、Björn C.G. Söderberg
DOI:10.1016/j.tet.2021.132331
日期:2021.8
A short and flexible synthesis of substituted indoles employing two palladium-catalyzed reactions, a Barluenga cross-coupling of p-tosylhydrazones with 2-nitroarylhalides followed by a palladium–catalyzed, carbon monoxide–mediated reductive cyclization has been developed. A one-pot, two-step methodology was further developed, eliminating isolation and purification of the cross-coupling product. This