Cyanophosphates (CPs) can be easily prepared from either ketones or aldehydes, and their reaction with NaN3–Et3N·HCl results in the formation of azidotetrazoles. Under microwave irradiation, successive fragmentation of the azidotetrazoles generates alkylidene carbenes that undergo [1,2]-rearrangement and are transformed into homologous alkynes. Treatment of ketone-derived CPs with TMSN3 and Bu2SnO
A step‐ and redox‐economic route toward aminoallenes from simplealkynes and N‐fluorobenzenesulfonimide (NFSI) was established viaselenium‐π‐acid catalysis. This unprecedented method significantly streamlines the assembly of heterosubstituted 1,3‐propadiene motifs and is characterized by a broad functional group tolerance.
Ni-Catalyzed Sonogashira Coupling of Nonactivated Alkyl Halides: Orthogonal Functionalization of Alkyl Iodides, Bromides, and Chlorides
作者:Oleg Vechorkin、Delphine Barmaz、Valérie Proust、Xile Hu
DOI:10.1021/ja906040t
日期:2009.9.2
Ni-catalyzed Sonogashira coupling of nonactivated, beta-H-containing alkyl halides, including chlorides, is reported. The coupling is tolerant to a wide range of functional groups, including ether, ester, amide, nitrile, keto, heterocycle, acetal, and aryl halide, in both coupling partners. The coupling can be selective for a specific C-X bond (X = I, Br, Cl) and allows for orthogonal functionalization
Ligand Exchange Reaction of Sulfoxides in Organic Synthesis. A Novel Method for Synthesizing Acetylenes from Carbonyl Compounds through β-Trifluoromethanesulfonyloxy Vinyl Sulfoxides
α-Sulfinyl ketones were prepared by the reaction of alkyl phenylsulfoxide or chloromethyl p-tolyl sulfoxide with aldehydes or methyl esters in high yields, and were converted to acetylenes through β-trifluoromethanesulfonyloxy vinyl sulfoxides by the ligand exchange reaction of the sulfinyl group.
Ligand exchange reaction of sulfoxides in organic synthesis: A novel method for synthesizing acetylenes and allenes from carbonyl compounds through sulfoxides having a trifluoro-methanesulfonyloxy group on the β-carbon
A novel method for synthesizing acetylenes and allenes from carbonyl compounds is described. Ligand exchange reaction of alkenylsulfoxides having a trifluoromethanesulfonyloxy group on the β-carbon, which were derived from α-alkyl β-ketosulfoxides, with n-BuLi gave disubstituted acetylenes in good yields. In the case of alkenylsulfoxides having both the trifluoromethanesulfonyloxy and aryl groups on