Heptafluoroisopropyl diazomethane (i-C<sub>3</sub>F<sub>7</sub>CHN<sub>2</sub>): in situ generation and synthesis of pyrazoles
作者:Pavel K. Mykhailiuk
DOI:10.1039/c7ob01579h
日期:——
A novel chemical reagent – heptafluoroisopropyl diazomethane (i-C3F7CHN2) – has been generated in situ in aqueous media. It readily reacts with electron-deficient alkynes towards polyfluorinated pyrazoles that are important in agrochemistry.
一种新型化学试剂-七氟异丙基重氮甲烷(iC 3 F 7 CHN 2)-在水性介质中原位生成。它容易与电子不足的炔烃反应生成对农业化学很重要的多氟化吡唑。
Highly Z-Selective Asymmetric Conjugate Addition of Alkynones with Pyrazol-5-ones Promoted by N,N′-Dioxide-Metal Complexes
Highly selective: The title reaction is achieved with high enantiomeric and geometric control and thermodynamically unstable (Z)‐enone derivatives are obtained as the major products (see scheme). The procedure tolerates a wide range of substrates to generate optically active pyrazolones with vinyl‐substituted quaternary stereocenters.
The highly Z‐selective asymmetric conjugateaddition of 3‐substituted oxindoles to alkynyl carbonyl compounds has been developed by using scandium complexes of chiral N,N′‐dioxides under mild conditions. The thermodynamically unstable Z‐olefin derivatives were obtained in excellent yields and high enantiomeric and geometric control. The catalyst was also found to be effective in the asymmetric acetylenic
An N,N′‐dioxide/zinc bis(trifluoromethylsulfonyl)imide complex has been developed as an efficient catalyst for the highly enantioselective Diels–Alderreaction of cyclopentadiene with alkynones. Various 2‐acyl substituted norbornadiene derivatives were obtained in moderate to high yields (up to 99 %) with good enantiomeric excesses (up to 95 %).
aging, sagging, and wrinkling, as well as inflammation and bacterial infections. In this study, to identify novel hyaluronidase inhibitors, we applied click chemistry for the modular synthesis of 370 triazoles in 96-well plates, starting with biphenyl azide. Utilizing an optimized turbidimetric screening assay in microplates, we identified Fmoc-containing triazoles and , as well as quinoline-containing