Rhodium-Catalyzed Enantioselective Hydrogenation of Tetrasubstituted α-Acetoxy β-Enamido Esters: A New Approach to Chiral α-Hydroxyl-β-amino Acid Derivatives
Asymmetric hydrogenation of tetrasubtitued α-acetoxy β-enamido esters with rhodium catalysts based on chiral diphosphine ligands provides an efficient and concise route to the synthesis of chiral α-hydroxyl-β-amino acid derivatives in excellent enantioselectivities. The products are valuable chiral building blocks in many biologically active compounds and have important applications in organic synthesis
Synthesis of trifluoromethylated 2<i>H</i>-azirines through Togni reagent-mediated trifluoromethylation followed by PhIO-mediated azirination
作者:Jiyun Sun、Xiaohua Zhen、Huaibin Ge、Guangtao Zhang、Xuechan An、Yunfei Du
DOI:10.3762/bjoc.14.123
日期:——
The reaction of enamine compounds with the Togni reagent in the presence of CuI afforded β-trifluoromethylated enamine intermediates, which were converted directly to biologically interesting trifluoromethylated 2H-azirines by an iodosobenzene (PhIO)-mediated intramolecular azirination in a one-pot process.
A new hypervalent iodine(<scp>iii</scp>/<scp>v</scp>) oxidant and its application to the synthesis of 2<i>H</i>-azirines
作者:Guangtao Zhang、Yuanxun Wang、Jun Xu、Jiyun Sun、Fengxia Sun、Yilin Zhang、Chenglin Zhang、Yunfei Du
DOI:10.1039/c9sc05536c
日期:——
in acetic acid was found to afford a novel hypervalentiodine compound, in the structure of which both iodine(III) and iodine(V) moieties coexist. The nitro groups at the ortho phenyl positions were found to be crucial in stabilizing this uncommon structure. This novel hypervalentiodine(III/V) oxidant is proved to be effective in realizing the synthesis of 2-unsubstitued 2H-azirines via intramolecular
邻硝基碘苯与间CPBA 在乙酸中反应可得到一种新型高价碘化合物,其结构中碘 ( III ) 和碘 ( V ) 部分共存。人们发现邻苯基位置的硝基对于稳定这种不常见的结构至关重要。这种新型高价碘( III / V )氧化剂被证明可以有效地实现通过分子内氧化氮丙啶合成2-未取代的2H-氮丙啶,这是现有已知的高价碘试剂无法有效实现的。
Synthesis of acyloxy-2<i>H</i>-azirine and sulfonyloxy-2<i>H</i>-azirine derivatives <i>via</i> a one-pot reaction of β-enamino esters, PIDA and carboxylic acid or sulfonic acid
作者:Pan Tang、Long Wen、Hao-Jie Ma、Yi Yang、Yan Jiang
DOI:10.1039/d2ob00364c
日期:——
acyloxy-2H-azirine and sulfonyloxy-2H-azirine derivatives was synthesized in moderate to good yields. This represents the first oxidative sulfonyloxylation/azirination of β-enamino esters with PIDA and sulfonic acid for access to sulfonyloxy-2H-azirine. Hypervalent iodine reagents enable cascade C–O/C–N bond formation. Furthermore, a possible reaction pathway was proposed based on the experimental
研究了 PIDA 介导的 β-烯氨基酯的氧化酰氧基化/氮丙啶化和磺酰氧基化/氮丙啶化。以中等至良好的收率合成了一系列官能化的 acyloxy-2 H -azirine 和 sulfonyloxy-2 H -azirine 衍生物。这代表了 β-烯氨基酯与 PIDA 和磺酸的第一次氧化磺酰氧基化/氮丙啶化以获得磺酰氧基-2 H-氮杂环丙烷。高价碘试剂能够形成级联 C-O/C-N 键。此外,根据实验结果提出了可能的反应途径。