Formation of α-iminoketones and α-diimines versus Favorskii rearrangement products from the reaction of α,α′-dibromoketones and primary amines
作者:Norbert De Kimpe、Luc D'Hondt、Luc Mones
DOI:10.1016/s0040-4020(01)92258-6
日期:1992.4
reaction of aliphatic acyclic α,α′-dibromoketones with primary amines gave rise to α-iminoketones and α-diimines. Both reaction products could be selectively obtained under appropriate reaction conditions. Sterically hindered α,α-dibromoketones did not react with primary amines, although, under forcing conditions the Favorskii rearrangement could be induced. In aqueous methanol, α,α′-dibromoketones reacted
Manganese Catalyzed Enantioselective Epoxidation of
<i>α</i>
,
<i>β</i>
‐Unsaturated Amides with H
<sub>2</sub>
O
<sub>2</sub>
作者:Roman V. Ottenbacher、Vladimir I. Kurganskiy、Evgenii P. Talsi、Konstantin P. Bryliakov
DOI:10.1002/adsc.202100198
日期:2021.6.8
Herewith, we report the enantioselectiveepoxidation of electron-deficient cis- and trans-α,β-unsaturated amides with the environmentally benign oxidant H2O2. The catalysts - manganese complexes with bis-amino-bis-pyridine and structurally related ligands - exhibit reasonably high efficiency (up to 100 TON) and excellent chemo- and enantioselectivity (up to 100% and 99% ee, respectively). Crucially
在此,我们报告了缺电子顺式和反式-α,β-不饱和酰胺与环境友好型氧化剂H 2 O 2的对映选择性环氧化反应。催化剂——锰与双氨基双吡啶和结构相关配体的配合物——表现出相当高的效率(高达 100 吨)和优异的化学和对映选择性(分别高达 100% 和 99% ee)。至关重要的是,顺式-enamides环氧化的对映选择性和产率用NH部分的存在,其效果可以通过之间的氢键相互作用来解释被显着增强的顺-烯酰胺底物和锰基氧转移物质。
Stereoselective preparation of methyl ()-cinnamates by favorskii rearrangement
作者:Thomas A Engler、Wolfgang Falter
DOI:10.1016/s0040-4039(00)84925-4
日期:1986.1
1,3-Dibromo-1-phenylacetones, readily prepared by direct bromination of the parent phenylacetone, react with methanolic sodium methoxide to yield stereoselectively methyl () cinnamates in good yield.
The first synthesis of N-Boc-protected tropanes by a [4+3] cycloaddition reaction is described. The Boc group has been cleanly removed demonstrating that this group would be very useful for the synthesis of ‘tropane-like’ scaffolds for combinatorial chemistry.