A versatile palladium catalyst system for Suzuki–Miyaura coupling of alkenyl tosylates and mesylates
作者:Pui Yu Wong、Wing Kin Chow、Kin Ho Chung、Chau Ming So、Chak Po Lau、Fuk Yee Kwong
DOI:10.1039/c1cc12240a
日期:——
A general and effectivepalladium system for Suzuki-Miyaura coupling of alkenyl electrophiles under mild reaction conditions is reported. With the Pd(OAc)(2)/CM-phos system, a variety of alkenyltosylates are coupled well with ArB(OH)(2). Moreover, the first successful examples of using alkenyl mesylates in alkenylation are also described.
Abstract A novel and convenient protocol for the synthesis of sulfonate derivatives via DABCO-catalyzed direct sulfonylation of 1-sulfonyl-1,2,3-triazoles to different enols has been established. This synthetic route could effectively avoid the use of transition metal catalysts and extra oxidants, and the target products could be obtained in good to excellent yields (75-86%) with wide substrate scope
Synthesis of 4-acylcoumarins by NHC-catalyzed nucleophilic substitution
作者:Yumiko Suzuki、Asuka Ando、Mizuki Nakagawa
DOI:10.1016/j.tetlet.2018.10.044
日期:2018.11
groups that originate from aromatic aldehydes by NHC-catalyzed umpolung. 4-Acylthiocoumarins and 2-acylquinolin-2-ones were also prepared using this method. These are the first examples of nucleophilicsubstitutions at the β-carbons of enones to afford γ-ketoenones.
Chromatography-Free and Eco-Friendly Synthesis of Aryl Tosylates and Mesylates
作者:Xiangyang Lei、Anusha Jalla、Mhd Abou Shama、Jamie Stafford、Billy Cao
DOI:10.1055/s-0034-1378867
日期:——
Two chromatography-free and eco-friendly protocols have been developed to synthesize aryl tosylates and mesylates by the tosylation and mesylation of the corresponding hydroxyarenes, respectively. These protocols are superior to other known ones regarding the simplicity, reaction time and conditions, the range of substrates, yields, and environmental friendliness.