Palladium‐Catalyzed Cascade Reaction of
<i>o</i>
‐Bromobenzaldehydes with
<i>N</i>
‐Sulfonylhydrazones: An Efficient Approach to the Naphthalene Skeleton
A new strategy for the construction of the naphthalene backbone is described. The reaction essentially starts from two simple aldehydes. The key step is enabled by a palladium‐carbene migratory insertion. After that, a sequence of reversible allylic alkylation and intramolecular condensation takes place to give the substituted naphthalene derivatives. Additional manipulations on the sulfonyl group
sulfinate salt, allylic sulfones were synthesized by palladium‐catalyzed cross‐coupling of aryl iodide with N‐tosylhydrazone. In this transformation, not only the diazo compound but also the sulfinate salt, which were both generated in situ from base‐mediated decomposition of the N‐tosylhydrazone, was used as nucleophilic partner.
Rhodium‐Catalyzed One‐Carbon Ring Expansion of Aziridines with Vinyl‐<i>N</i>‐triftosylhydrazones for the Synthesis of 2‐Vinyl Azetidines
作者:Yongquan Ning、Hongzhu Chen、Yongyue Ning、Jin Zhang、Xihe Bi
DOI:10.1002/anie.202318072
日期:2024.3.18
A general skeletal ring expansion strategy for the direct conversion of aziridines into 2-vinyl azetidines via one-carbon insertion using vinyl-N-triftosylhydrazones is described. The method is scalable, tolerates diverse functional groups, and is amenable to the synthesis of medicinally relevant molecules.
Base-Mediated Denitrogenative Sulfonylation/Benzannulation of Conjugated <i>N</i>-Sulfonylhydrazones with 3-Formylchromones for the Construction of Polyfunctionalized Biaryl Sulfones
作者:Rajeev Shrestha、Hari Datta Khanal、Peter Yuosef M. Rubio、Sonaimuthu Mohandoss、Yong Rok Lee
DOI:10.1021/acs.orglett.0c02724
日期:2020.10.2
of conjugated N-sulfonylhydrazones and 3-formylchromones for the synthesis of diverse biaryl sulfones is described. The approach facilitates new C–C and C–Sbondformation via the cascade diazo formation/Michael addition/ring opening/denitrogenative sulfonylation/intramolecular cycloaddition/dehydration and introduces diverse functional groups onto biaryl sulfones. The synthesized compounds are converted