Hf(IV)-Catalyzed Enantioselective Epoxidation of <i>N</i>-Alkenyl Sulfonamides and <i>N</i>-Tosyl Imines
作者:José Luis Olivares-Romero、Zhi Li、Hisashi Yamamoto
DOI:10.1021/ja211880s
日期:2012.3.28
Asymmetric epoxidation of allylic and homoallylic amine derivatives catalyzed by Hf(IV)-bishydroxamic acid complexes is described. Under similar conditions, aldimine and ketimine produced oxaziridines. The sulfonyl group is demonstrated to be an effective directing group for these transformations.
Compounds of formula (I), wherein R
1
, p, R
2
, q, R
3
and R
4
are defined within, and a pharmaceutically acceptable salts and in vivo hydrolysable esters are described. Also described are processes for their preparation and their use as medicaments, particularly medicaments for producing a cell cycle inhibitory (anti-cell-proliferation) effect in a warm-blooded animal, such as man.
1
Ring-Expansion Reactions of Epoxy Amides and Enamides: Functionalized Azetidines, Dihydrofurans, Diazocanes, or Dioxa-3-azabicyclonon-4-enes?
作者:Suraj、K. C. Kumara Swamy
DOI:10.1021/acs.joc.2c00268
日期:2022.5.20
3-dihydrofurans, or the unorthodox dioxa-3-azabicyclonone-4-ene motifs are the products from transition metal-free reaction between N-oxiranylmethyl benzenesulfonamide and β-chloro-cinnamaldehyde, depending on whether one uses either NaI/K2CO3 or LiBr/K2CO3. These ring expansion reactions involve enamide (X-ray evidence) derived from N-oxiranylmethyl benzenesulfonamide and β-chloro-cinnamaldehyde as
功能化的氮杂环丁烷、2,3-二氢呋喃或非正统的二氧杂环己烷-3-氮杂双环酮-4-烯基序是N-环氧乙烷基甲基苯磺酰胺和 β-氯-肉桂醛之间的无过渡金属反应的产物,具体取决于是否使用 NaI /K 2 CO 3或 LiBr/K 2 CO 3。这些扩环反应涉及衍生自N-环氧乙烷基甲基苯磺酰胺和 β-氯肉桂醛作为中间体的烯酰胺(X 射线证据) 。N-环氧乙烷基甲基苯磺酰胺本身在加热时产生易于分离的结晶异构重氮杂环烷,其可通过X-射线晶体学表征。