Highly efficient gold(I)-catalyzed Overman rearrangement in water
نویسندگان
چکیده
A highly efficient gold(I)-catalyzed Overman rearrangement of allylic trichloroacetimidates to allylic trichloroacetamides in water is reported. With this environmentally benign and scalable protocol, a series of C3-alkyl substituted allylic trichloroacetamides were synthesized in good to high yields.
منابع مشابه
Synthesis of Allylic Amide Functionalized 2H-Chromenes and Coumarins Using a One-Pot Overman Rearrangement and Gold(I)-Catalyzed Hydroarylation.
A four-step synthesis of allylic trichloroacetimidates bearing a 2-proparyloxyaryl group has been developed from readily available 2-hydroxybenzaldehydes, and these have been used for the preparation of allylic amide derived 2H-chromenes using an Overman rearrangement and a 6-endo-dig hydroarylation. High yields of the 2H-chromenes were achieved using a stepwise approach involving an Overman re...
متن کاملGold(I)-catalyzed ring expansion of cyclopropanols and cyclobutanols.
The rearrangement of 1-alkynyl cyclobutanols and cyclopropanols to alkylidene cycloalkanones catalyzed by cationic triarylphosphine gold(I) complexes is described. The reaction tolerates terminal alkynes as well as alkyl, aryl, and halo-substitution at the acetylenic position and stereoselectively provides a single olefin isomer. The gold(I)-catalyzed rearrangement is stereospecific with regard...
متن کاملOne-pot Efficient Oximation-Beckmann Rearrangement of Ketones Catalyzed by Fe3O4 Under Solvent-free Conditions
Fe3O4 nanoparticles were employment as an efficient and magnetically separable Nano catalyst for the synthesis of amides via one-pot Beckmann rearrangement of ketones under solvent-free conditions. Various secondary amides were synthesized by this method in moderate to good yields. The catalyst showed high thermal stability and was recovered and reused at least five times without any considerab...
متن کاملPreparation of anti-Vicinal Amino Alcohols: Asymmetric Synthesis of d-erythro-Sphinganine, (+)-Spisulosine, and d-ribo-Phytosphingosine
Two variations of the Overman rearrangement have been developed for the highly selective synthesis of anti-vicinal amino alcohol natural products. A MOM ether-directed palladium(II)-catalyzed rearrangement of an allylic trichloroacetimidate was used as the key step for the preparation of the protein kinase C inhibitor D-erythro-sphinganine and the antitumor agent (+)-spisulosine, whereas the Ov...
متن کاملGold(I)-catalyzed formation of furans by a Claisen-type rearrangement of ynenyl allyl ethers
A series of ynenyl allyl ethers were rearranged into polysubstituted furans in the presence of a gold(I) catalyst. It is proposed that the transformation involves a Claisen-type rearrangement that allows the efficient creation of quaternary centers under mild experimental conditions.
متن کامل