A convergent approach to (R)-Tiagabine by a regio- and stereocontrolled hydroiodination of alkynes
作者:Giuseppe Bartoli、Roberto Cipolletti、Giustino Di Antonio、Riccardo Giovannini、Silvia Lanari、Mauro Marcolini、Enrico Marcantoni
DOI:10.1039/c005042c
日期:——
The occurrence of unsaturated systems in natural products combined with the mildness and the wide range of applicability of CeCl3 promoted methodologies suggest several potential future synthetic applications within the field of total synthesis of biologically active molecules. On this concept, the use of CeCl3·7H2O–NaI system as an efficient heterogeneous promoter has been highlighted in the iodofunctionalization of carbon–carbon triple bonds. The study has shown that this method would be particularly interesting for the stereoselective formation of trisubstituted (Z)- or (E)-iodoalkenes by simply changing the nature of the solvent. The methodology has been successfully applied to the synthesis of (R)-1-[4,4-bis-(3-methyl-2-thienyl)-3-butenyl]-3-piperidinecarboxylic acid 1, named (R)-Tiagabine, which is a potent and selective γ-aminobutyric acid (GABA) uptake inhibitor with proven anticonvulsant efficacy in humans.
Cyclic Vinyl(aryl)iodonium Salts: Synthesis and Reactivity
作者:Konrad Kepski、Craig R. Rice、Wesley J. Moran
DOI:10.1021/acs.orglett.9b02540
日期:2019.9.6
A convenient, highly regioselective synthesis of five-membered cyclic vinyl(aryl)iodoniumsalts directly from β-iodostyrenes is presented. An X-ray crystal structure confirms the identity of these heterocycles. These λ3-iodanes can be converted rapidly into functionalized arylacetylenes by treatment with mild base or undergo SNV reactions with nonbasic nucleophiles.
Metallaphotoredox catalysis enables facile (trifluoromethyl)thiolation of alkenyl iodides
作者:Eric R. King、Maxime Tarrago、Avipsa Ghosh
DOI:10.1039/d3cy01394d
日期:——
(Ni)-catalyzed, photoredox-based approach for the trifluoromethylthiolation of alkenyl iodides to access diverse and biologically relevant alkenyl-SCF3 compounds under mild and air-tolerant conditions. The developed methodology tolerates a broad range of substituted (hetero)aromatic and aliphatic alkenyl iodides, exhibiting general Z selectivity arising from an in situ photoisomerization mechanism
A new approach for highly efficient and enantioselective alkenylation of aldehydes promoted by an easily accessible cobalt-based complex was developed. This protocol represents the first example of incorporating a wide range of alkenyl groups with diversified substitution patterns as well as axial stereogenicity into enantioenriched allylic alcohols.