Heterocyclic compounds can be divided into two categories: alicyclic heterocycles and aromatic heterocycles. Compounds whose heterocycles in the molecular skeleton cannot reflect aromaticity are called alicyclic heterocyclic compounds. Compound: 119639-24-6, is researched, Molecular C7H11NO3S, about Palladium-Catalyzed [3 + 2] Cycloaddition via Twofold 1,3-C(sp3)-H Activation, the main research direction is palladium catalyzed cycloaddition carbon hydrogen bond activation; amide lactam cycloaddition maleimide.Category: isothiazole.
Cycloaddition reactions provide an expeditious route to construct ring systems in a highly convergent and stereoselective manner. For a typical cycloaddition reaction to occur, however, the installation of multiple reactive functional groups (π-bonds, leaving group, etc.) are required within the substrates, compromising the overall efficiency or scope of the cycloaddition reaction. Here, we report a palladium-catalyzed [3 + 2] reaction that utilizes C(sp3)-H activation to generate the three-carbon unit for formal cycloaddition with maleimides. We implemented a strategy where the initial C(sp3)-H activation/olefin insertion would trigger a relayed, second remote C(sp3)-H activation to complete a formal [3 + 2] cycloaddition The diastereoselectivity profile of this reaction resembles that of a typical pericyclic cycloaddition reaction in that the relationships between multiple stereocenters are exquisitely controlled in a single reaction. The key to success was the use of weakly coordinating amides as the directing group, as undesired Heck or alkylation pathways were preferred with other types of directing groups. The use of the pyridine-3-sulfonic acid ligands is critical to enable C(sp3)-H activation directed by this weak coordination. The method is compatible with a wide range of amide substrates, including lactams, which lead to novel spiro-bicyclic products. The [3 + 2] product is also shown to undergo a reductive desymmetrization process to access chiral cyclopentane bearing multiple stereocenters with excellent enantioselectivity. Cycloaddition reactions provide an expeditious route to construct ring systems in a highly convergent and stereoselective manner. For a typical cycloaddition reaction to occur, however, the installation of multiple reactive functional groups (π-bonds, leaving group, etc.) is required within the substrates, compromising the overall efficiency or scope of the cycloaddition reaction. Here, we report a palladium-catalyzed [3 + 2] reaction that utilizes twofold C(sp3)-H activation to generate the three-carbon unit for formal cycloaddition The initial β-C(sp3)-H activation of aliphatic amide, followed by maleimide insertion, triggers a relayed, second C(sp3)-H activation to complete a formal [3 + 2] cycloaddition The key to success was the use of weakly coordinating amide as the directing group, as previous studies have shown that Heck or alkylation pathways are preferred when stronger-coordinating directing groups are used with maleimide coupling partners [e.g., N,N-dimethylpivalamide + N-(4-nitrophenyl)maleimide → I (87%, dr 6:1)]. To promote the amide-directed C(sp3)-H activation step, the use of pyridine-3-sulfonic acid ligands is crucial. This method is compatible with a wide range of amide substrates, including lactams, which lead to spiro-bicyclic products. The [3 + 2] product is also shown to undergo a reductive desymmetrization process to access chiral cyclopentane bearing multiple stereocenters with excellent enantioselectivity.
Compounds in my other articles are similar to this one(2-(tert-Butyl)isothiazol-3(2H)-one 1,1-dioxide)Category: isothiazole, you can compare them to see their pros and cons in some ways,such as convenient, effective and so on.
Reference:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com