Michaelreactions between trimethylsilyl enolates and α,β-unsaturated carbonyl compounds by using a Lewis base catalyst such as lithium benzamide 4 or lithium succinimide 5 in DMF proceeded smoothl...
The Michael Reaction of Silyl Enol Ethers with α,β-Unsaturated Eetones and Acetals in the Presence of Titanium Tetraalkoxide and Titanium Tetrachloride
Silyl enol ethers react with α,β-unsaturated ketones and esters in the presence of TiCl4 or in the coexistence of TiCl4 and Ti(Oi-Pr)4 to give 1,5-dicarbonyl compounds in good yields. The reactions of acetals derived from α,β-unsaturated ketones with silyl enol ethers in the coexistence of TiCl4 and Ti(Oi-Pr)4, followed by successive addition of 1,2-ethanedithiol, give the Michael products, δ-keto
simple and efficient protocol for the construction of substituted piperazines, piperidines, thiomorpholines, decahydroquinolines, perhydrocyclopenta[b]pyridine, and pyrrolidines bearing N-hydroxy substituents through intramolecularreductivecyclization of diketoximes using sodium cyanoborohydride is described.
Lithium acetate-catalyzed Michael reactionbetween trimethylsilyl enolates and α,β-unsaturated carbonyl compounds in DMF proceeded smoothly to afford the corresponding Michael-adducts in good to hi...
Alkali metal hydride or aqueous hydroxide induced conjugate addition of trimethylsilyl enol ethers to enones. A convenient alternative to Lewis acid mediated reaction
作者:Vishwanath M. Swamy、Amitabha Sarkar
DOI:10.1016/s0040-4039(97)10771-7
日期:1998.3
Conjugate addition to enones by enolates derived from base-induced cleavage of OSi bond of trimethylsilyl enol ethers, yields 1,5-dicarbonyl compounds in good yields.