Aza-heterocyclic frameworks through intramolecular π-system trapping of spiro-<i>N</i>-acyliminiums generated from isoindolinone
作者:Sarra Chortani、Mohamed Othman、Ata Martin Lawson、Anis Romdhane、Hichem Ben Jannet、Michael Knorr、Lukas Brieger、Carsten Strohmann、Adam Daïch
DOI:10.1039/d0nj04052e
日期:——
spiro-isoindolinone-imides. The latter were produced in large scale in three steps from homophthalic acid. These imides were useful to provide in one step isoindolinones bearing hydroxymethyl-amide functions, tethered at quaternary carbon centre with promising biological issues. Submitted to Brønsted (TFA neat) and Lewis acid (trimethylsilyltrifluoro-methanesulfonic (TMSOTf) 10 mol%), the spiro-acetoxylactams undergo
ammonium salt‐catalyzed synthesis of chiral 3,3‐disubstituted isoindolinones bearing a heteroatom functionality in the 3‐position. A broad variety of differently substituted CF3S‐ and RS‐derivatives were obtained with often high enantioselectivities when using Maruoka's bifunctional chiral ammonium salt catalyst. In addition, a first proof‐of‐concept for the racemic synthesis of the analogous F‐containing
我们在此报告了铵盐催化合成在3位带有杂原子官能团的手性3,3-二取代异吲哚啉酮。使用 Maruoka 的双功能手性铵盐催化剂时,可以获得多种不同取代的 CF 3 S 和 RS 衍生物,且通常具有较高的对映选择性。此外,还获得了类似含 F 产品外消旋合成的第一个概念验证,从而获得了相当稳定的 α-F-α-氨基酸衍生物的罕见例子之一。
Silver-catalyzed spirolactonization: first synthesis of spiroisoindole-γ-methylene-γ-butyrolactones
作者:Mohamed M. Rammah、Mohamed Othman、Kabula Ciamala、Carsten Strohmann、Mohamed B. Rammah
DOI:10.1016/j.tet.2008.01.137
日期:2008.4
gamma-Acetylenic carboxylic acids are cyclized to spirolactones under mild conditions, in the presence of Ag2CO3 catalyst. The corresponding spiro-5-alkylidene-gamma-butyrolactones were isolated in high yields, and this process constitutes an easy and efficient route to analogous structures of natural products of biological interest. (c) 2008 Elsevier Ltd. All rights reserved.
Halolactonization of g-Acetylenic Acids: Synthesis of Novel Spiroisoindole Halobutyrolactones
作者:Mohamed Othman、Mohamed M. Rammah、Moncef Msaddek、Mohamed B. Rammah
DOI:10.3987/com-08-11370
日期:——
A Convenient Synthesis of Novel Spiroisoindole γ-Halobutyrolactones via Halocyclization of γ-Ethylenic Acids
作者:Mohamed Othman、Mohamed M. Rammah、Kabula Ciamala、Michael Knorr、Carsten Strohmann、Mohamed B. Rammah
DOI:10.3987/com-09-11787
日期:——
gamma-Ethylenic carboxylic acids are cyclized to spirolsoindolone gamma-halomethylbutyrolactones, in the presence of NBS or NIS and K2CO3. The corresponding haloaspirobutyrolactones were isolated in high yields (57-95%).