Palladium(0)‐catalysed hydro‐alkylation or ‐alkenylation of alkoxyallenes with N‐tosylhydrazones gives direct access to conjugated and skipped 1‐alkoxydienes with high efficiency and excellent functional‐group compatibility. The reaction is proposed to involve the in situ‐formed t‐butanol as proton source in the key step of the allylpalladium(II) species generation. Moreover, lithium iodide or iodobenzene
Nickel-Catalyzed Regioselective Hydrothiolation of Allenes Enabled by Visible-Light Photoredox Catalysis
作者:Hui Xie、Bernhard Breit
DOI:10.1021/acs.orglett.4c01027
日期:2024.5.31
Hydrothiolation presents an attractive way to transform allenes into allylic thioethers. Herein, we described an efficient visible-light photoredox-promoted nickel-catalyzed hydrothiolation of allenes with functionalized aromatic and aliphatic thiols. This synergistic catalytic system exhibits unprecedentedly high reactivities and regiocontrol for the construction of allylic thioethers, representing
Catalytic alkynylation of diverse ketones and aldehydes using nonmetallic benzyltrimethylammonium hydroxide or a basic resin of the hydroxide type in DMSO is described. Aliphatic or alicyclic carbonyl partners gave satisfactory results, whereas aromatic ones afforded products with low yields. When aromatic aldehydes were reacted with phenylacetylene, enones such as chalcone derivatives were obtained in place of ynols. These organobase-catalyzed systems provide a practical nonmetallic protocol for C-C bond formation.
An easy access to α,β-unsaturated thioacylsilanes: a useful route to silylated 1,2-dithiins
Treatment of different silylated allenes with hexamethyldisilathiane (HMDST) in the presence of CoCl2.6H(2)O affords an easy and high yielding access to alpha,beta-unsaturated thioacylsilanes, which undergo a self-dimerization reaction to afford polyfunctionalized 1,2-dithiins as the major products. (C) 2003 Elsevier Science Ltd. All rights reserved.
CRABBE P.; FILLION H.; ANDRE D.; LUCHE J.-L., J. CHEM. SOC. CHEM. COMM., 1979, NO 19, 859-860