6554-73-0Relevant articles and documents
Reactions of 2,3-Dibromo-2-methylpropanamides Promoted by Potassium tert-Butoxide
Galeeva, A. M.,Miftakhov, M. S.,Selezneva, N. K.,Valiullina, Z. R.
, p. 1643 - 1649 (2021/12/13)
Abstract: 2,3-Dibromo-2-methylpropanamides with different substituents on the nitrogen atom were synthe-sized, and their transformations by the action of potassium tert-butoxide in THF were studied. 2,3-Dibromo-N-(4-methoxyphenyl)-2-methylpropanamide and 2,3-dibromo-N-(2,5-dibromo-4-methoxyphenyl)-2-methyl-propan-amide reacted with 1–2 equiv of t-BuOK to give the corresponding N-substituted 3-bromo-3-methyl- and 3-methylideneazetidin-2-ones with acceptable yields and selectivity. Increase of the amount of t-BuOK to 3–5 equiv led to significant reduction of the yield of vinyl bromides and 3-methylideneazetidin-2-ones. On the other hand, the reaction of 2,3-dibromo-N-(tert-butyl)-2-methylpropanamide with t-BuOK afforded 3-(tert-bu-toxymethyl)-1-tert-butylazetidin-2-one with a good yield and selectivity.
Catalytic dicyanative 5-exo- And 6-endo-cyclization triggered by cyanopalladation of alkynes
Arai, Shigeru,Koike, Yuka,Nishida, Atsushi
experimental part, p. 893 - 900 (2010/07/06)
A stereoselective dicyanative 5-exo- and 6endo-cyclization using various enynes has been investigated. The mode of cyclization is critically controlled by the structure of the substrates. For example, N-allyl derivatives prefer 5-exo-cyclization, while methacryloyl amides are transformed to the corresponding lactams with tetra substituted carbons at the alpha-position via 6-endo-cyclization. Both reactions include syn-cyanopalladation to carbon≡carbon triple bonds in the initial step, and sequential cyclization followed by reductive elimination in one operation enables the construction of the highly functionalized nitrogen heterocycles. The scope of suitable substrates and a proposed mechanism are also described.
Synthesis, fragmentations and rearrangements of 3-(1-haloalkyl) oxaziridines
De Kimpe, Norbert,De Corte, Bart
, p. 7345 - 7362 (2007/10/02)
A variety of new 3-(1-haloalkyl)oxaziridines was synthesized by oxidation of α-chloro-, α-bromo-, α,α-dichloro-, α,α-dibromo- and α,α,α-trichloroaldimines with meta-chloroperbenzoic acid. Attempts to induce dehydrohalogenation into the elusive methyleneoxaziridines were unsuccessful. However, presumptive evidence is presented that 2-t-butyl-3-(trichloromethyl)oxaziridine is dehydrochlorinated into a transient methyleneoxaziridine, which underwent valence isomerization into an intermediate iminooxirane, the latter being fragmented into t-butyl isocyanide. Various types of reactions of the title compounds are reported. Among others, 2-alkyl-3-(1-chloro-1-methyl) ethyloxaziridines rearranged with methyllithium into 2-(N-alkyl)aminoisobutyraldehydes.