1429936-58-2Relevant academic research and scientific papers
Metal- And Base-Free C(sp2)-H Arylsulfonylation of Enamides for Synthesis of (E)-β-Amidovinyl Sulfones via the Insertion of Sulfur Dioxide
Chen, Lei,Zhou, Mi,Shen, Lin,He, Xiaochun,Li, Xiong,Zhang, Xuemei,Lian, Zhong
supporting information, p. 4991 - 4996 (2021/06/30)
A metal- and base-free C(sp2)-H direct arylsulfonylation of secondary and tertiary enamides with aryldiazonium salts and ex situ generated SO2 (from SOgen) is presented. This method runs smoothly to produce β-amidovinyl sulfones with excellent stereoselectivities in moderate to excellent yields. Moreover, this strategy features good functional group tolerance and environmentally benign reaction conditions. Mechanistic experiments indicate that this sulfonylation may proceed in a radical pathway.
PQS-enabled visible-light iridium photoredox catalysis in water at room temperature
Bu, Mei-Jie,Cai, Chun,Gallou, Fabrice,Lipshutz, Bruce H.
supporting information, p. 1233 - 1237 (2018/03/26)
An amphoteric PQS-attached photocatalyst has been prepared that undergoes self-aggregation in water into nanomicelles. This covalently bound species enables Ir-based photoredox catalysis to be conducted in the absence of additives or co-solvents. Representative reactions are described using this new catalytic system, which require no additional investment of external energy in the form of heating or cooling. The entire aqueous reaction mixture readily undergoes in-flask recycling and thus, represents a sustainable precious metal technology.
Tosvinyl and besvinyl as protecting groups of imides, azinones, nucleosides, sultams, and lactams. Catalytic conjugate additions to tosylacetylene
Petit, Elena,Bosch, Llus,Font, Joan,Mola, Laura,Costa, Anna M.,Vilarrasa, Jaume
, p. 8826 - 8834 (2015/01/08)
The use of the 2-(4-methylphenylsulfonyl)-ethenyl (tosvinyl, Tsv) group for the protection of the NH group of a series of imides, azinones (including AZT), inosines, and cyclic sulfonamides has been examined. The Tsvprotected derivatives are obtained in excellent yields by conjugate addition to tosylacetylene (ethynyl p-tolyl sulfone). The stereochemistry of the double bond can be controlled at will: with only 1 mol % of Et3N or with catalytic amounts of NaH, the Z stereoisomers are generated almost exclusively, while the E isomers are obtained using a stoichiometric amount of DMAP. Analogous phenylsulfonylvinyl-protected groups (with the besvinyl or Bsv group instead of Tsv) are obtained stereospecifically by reaction with (Z)- or (E)-bis(phenylsulfonyl)ethene. For lactams and oxazolidinones, this last method is much better. The Tsv and Bsv groups are stable in the presence of non-nucleophilic bases and to acids. They can be removed highly effectively via a conjugate addition-elimination mechanism using pyrrolidine or sodium dodecanethiolate as nucleophiles.
C-H functionalization of enamides: Synthesis of β-amidovinyl sulfones via visible-light photoredox catalysis
Jiang, Heng,Chen, Xuejiao,Zhang, Yan,Yu, Shouyun
supporting information, p. 809 - 813 (2013/04/10)
A mild, practical and environmentally friendly strategy to prepare β-amidovinyl sulfones has been developed based on the sulfonation of enamides or enecarbamates via visible-light photoredox catalysis. Direct C-H functionalizations of enamides or enecarbamates under the optimized conditions proceeded with a wide scope of substrates and remarkable selectivity to give functionalized vinyl sulfones with good to excellent yields. Copyright
