Efficient synthesis of organic thioacetates in water
作者:F. Olivito、P. Costanzo、M. L. Di Gioia、M. Nardi、Oliverio M.、A. Procopio
DOI:10.1039/c8ob01896k
日期:——
Thioacetates as precursors of thiols are interesting starting points for synthesizing other organosulfur compounds. Herein, we propose a simple, efficient and fast method to obtain organic thioacetates using water as a solvent. Taking into account the great attention that has been paid toward environmentally friendly synthetic procedures in the past decades, we prove the role and the strength of the
One-Pot Three-Component Synthesis of Vicinal Diamines via In Situ Aminal Formation and Carboamination
作者:Ugo Orcel、Jerome Waser
DOI:10.1002/anie.201607318
日期:2016.10.4
A synthesis of vicinal diamines via in situ aminalformation and carboamination of allyl amines is reported. Employing highly electron‐poor trifluoromethyl aldimines in their stable hemiaminal form was key to enable both a fast and complete aminalformation as well as the palladium‐catalyzed carboamination step. The conditions developed allow the introduction of a wide variety of alkynyl, vinyl, aryl
Palladium-Catalyzed Vicinal Amino Alcohols Synthesis from Allyl Amines by In Situ Tether Formation and Carboetherification
作者:Ugo Orcel、Jerome Waser
DOI:10.1002/anie.201500636
日期:2015.4.20
Vicinalaminoalcohols are important structural motifs of bioactive compounds. Reported herein is an efficient method for their synthesis based on the palladium‐catalyzed oxy‐alkynylation, oxy‐arylation, or oxy‐vinylation of allylic amines. High regio‐ and stereoselectivity were ensured through the in situformation of a hemiaminal tether using the cheap commercially available trifluoroacetaldehyde
Domino reaction of a gold catalyzed 5-<i>endo-dig</i> cyclization and a [3,3]-sigmatropic rearrangement towards polysubstituted pyrazoles
作者:Arno Verlee、Thomas Heugebaert、Tom van der Meer、Pavel Kerchev、Frank Van Breusegem、Christian V. Stevens
DOI:10.1039/c8ob02807a
日期:——
important heterocyclic compounds with a broad range of biological activities. A new procedure toward tri- or tetrasubstituted pyrazoles has been developed, via a one-pot gold catalyzed synthesis from hydrazines with alkynyl aldehydes or ketones. The reaction proceeds through consecutive hydrazone formation, 5-endo-dig cyclization and an aza-Claisen rearrangement resulting in the desired polysubstitued pyrazoles
from the same N-allyl precursor by stereodivergent alkene isomerization. The reaction, formally a nucleophilic substitution at an sp2 carbon atom, allows the direct regioselective incorporation of mono-, di-, tri-, and tetrasubstituted olefins at the α-carbon of amino acid derivatives. The initially formed 5-alkenyl iminohydantoins may be hydrolyzed and oxidatively deprotected to yield hydantoins and unsaturated