In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Palladium-Catalyzed [3 + 2] Cycloaddition via Twofold 1,3-C(sp3)-H Activation, published in 2020-09-30, which mentions a compound: 119639-24-6, mainly applied to palladium catalyzed cycloaddition carbon hydrogen bond activation; amide lactam cycloaddition maleimide, COA of Formula: C7H11NO3S.
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.
Although many compounds look similar to this compound(119639-24-6)COA of Formula: C7H11NO3S, numerous studies have shown that this compound(SMILES:O=C(C=C1)N(C(C)(C)C)S1(=O)=O), has unique advantages. If you want to know more about similar compounds, you can read my other articles.
Reference:
Isothiazole – Wikipedia,
Isothiazole – ScienceDirect.com