The metal-free oxidative alkene methylation/alkynylation of 1,4-enyn-3-ols with an organic peroxide as the methyl source has been developed, which provides straightforward and practical access to the challenging quaternary-carbon-containing but-3-yn-1-ones. The method is reasoned to go through methylation of functional alkenes utilizing dicumyl peroxide as the methylating reagent and subsequent intermolecular
Flexible Construction of Functionalized‐Pyrroles under Palladium or Copper Catalysis in the Presence of BF
<sub>3</sub>
⋅ Et
<sub>2</sub>
O
作者:Yin Liu、Teng Liu、Biwei Yan、Kun Wei、Wusheng Guo
DOI:10.1002/adsc.202101292
日期:2022.3
friendly operations with the generation of only water as byproduct. The generality of this protocol is demonstrated by the successful preparation of a range of di-, tri-, tetra- and pentasubstituted pyrroles. This methodology is amenable for the synthesis and derivatization of bioactive compounds.
我们开发了一种灵活的方法,能够在 BF 3 ⋅ Et 2 O 的存在下,在钯或铜催化下获得高度官能化的吡咯。这种催化方法利用市售胺作为反应伙伴,具有广泛的范围、可扩展和友好的操作仅产生水作为副产品。该协议的普遍性通过一系列二、三、四和五取代吡咯的成功制备得到证明。该方法适用于生物活性化合物的合成和衍生化。
Tandem Aza Michael Addition–Vinylogous Nitroaldol Condensation: Construction of Highly Substituted <i>N</i>-Fused 3-Nitropyrazolopyridines
A base-mediated tandem aza-Michael addition–vinylogous nitroaldol condensation has been described between 3,5-dialkyl 4-nitropyrazoles and alkynyl ketones/aldehydes. This transition metal-free atom economical transformation occurred via C–N and C═C bond formations in one step with the elimination of water. The construction of a variety of highly substituted N-fused 3-nitropyrazolopyridine derivatives
3-exo-dig cyclization with 1,2-alkynyl migration of 1,4-enynes with simple cycloalkanes was established, enabling C–C breaking and reconstruction to access a wide range of α-alkynyl ketones with generally good yields by FeCl2/di-tert-butyl peroxide (DTBP) as a catalytic oxidation system. Radical-induced C(sp3)–H functionalization of cycloalkanes was realized, leading to the direct formation of C(sp3)–C(sp3)
one-pot approach for the synthesis of quinolines from o-aminothiophenol and 1,3-ynone under mild conditions is disclosed. With the aid of ESI-MS analysis and parallel experiments, a three-step mechanism is proposed-a two-step Michael addition-cyclization condensation step leading to intermediate 1,5-benzothiazepine catalyzed by zirconocene amino acid complex Cp2Zr(η1-C9H10NO2)2, followed by I2-mediated