Development of Novel Diastereoselective Alkenylation of Enolates Using Alkenylselenonium Salts

Abstract

[reaction: see text] A novel alkenylation of enolates using alkenylselenonium salts is described. A reaction of lithium enolates, which were prepared in situ by the reaction of LiHMDS and carbonyl compounds, with alkenylselenonium salts gave the ethenylation products of carbonyl compounds in high yield. Diastereoselective alkenylation was also accomplished by the reaction of the enolates derived from N-acyl-1,3-oxazolidin-2-ones with the alkenylselenonium salt to afford good results (up to 92% yield and up to 95% de).

Recent Advances in Organoselenium Chemistry

“…Kataoka et al investigated the reaction of chiral enolates with alkenyl selenonium salts reacting as electrophiles. The diastereoselectivity of this reaction is dependant on the nature of the selenonium salts, with dimethylalkenyl selenonium salt 38 exclusively the Z ‐isomer 39 was obtained in high yield 88. Reaction with 1,3‐dicarbonyl compounds afford cyclopropane derivatives 40 via a novel Michael Favorskii type reaction (Scheme ) 89…”

Oxazolidin-2-one Ring, a Popular Framework in Synthetic Organic Chemistry Part 2 [1]. Applications and Modifications

“…The alkenylation of enolates (Scheme 111) derived from Nacyl-oxazolidin-2-ones 541 with alkenylselenonium salt affords the products 286 with high yields (up to 92%) and diastereoselectivity [173].…”

Pd-Catalyzed α-Arylation of Nitriles and Esters and γ-Arylation of Unsaturated Nitriles with TMPZnCl·LiCl

“…In contrast to enolate arylations, the corresponding alkenylation is particularly rare , and is unknown for nitriles. The alkenylation of unsaturated nitriles 7b and 9 was readily achieved with TMPZnCl·LiCl ( 1 ) with complete γ-regioselectivity.…”