Sequential Combination of Ruthenium-, Base-, and Gold-Catalysis - A New Approach to the Synthesis of Medicinally Important Heterocycles
作者:Dhevalapally B. Ramachary、Vidadala V. Narayana
DOI:10.1002/ejoc.201100040
日期:2011.7
synthesis of medicinallyimportantheterocycles was achieved through the sequential combination of ring-closing metathesis, base-induced ring opening (BIRO), hydroamination, and a Diels-Alder reaction of functionalized allyl-(2-allylphenyl)amines in the presence of a catalytic amount of Grubbs' second-generation catalyst, base (tBuOK), and [AuCl(PPh 3 )]/AgOTf. Herein, we also demonstrate the important electronic
Asymmetric Palladium-Catalyzed Alkene Carboamination Reactions for the Synthesis of Cyclic Sulfamides
作者:Zachary J. Garlets、Kaia R. Parenti、John P. Wolfe
DOI:10.1002/chem.201600887
日期:2016.4.18
The synthesis of cyclic sulfamides by enantioselective Pd‐catalyzed alkene carboamination reactions between N‐allylsulfamides and aryl or alkenyl bromides is described. High levels of asymmetric induction (up to 95:5 e.r.) are achieved using a catalyst composed of [Pd2(dba)3] and (S)‐Siphos‐PE. Deuterium‐labelling studies indicate the reactions proceed through syn‐aminopalladation of the alkene and
Facile Access to Bicyclic Sultams with Methyl 1-Sulfonylcyclopropane-1-carboxylate Moieties
作者:Valentin A. Rassadin、Aleksandr A. Tomashevskiy、Viktor V. Sokolov、Arne Ringe、Jörg Magull、Armin de Meijere
DOI:10.1002/ejoc.200900113
日期:2009.6
4-dibromobutyl)(methoxycarbonyl)methanesulfanilides upon treatment with potassium carbonate in DMF furnish methyl 3-aryl-2,2-dioxo-2-thia-3-azabicyclo[n.1.0]alkane-1-carboxylates in yields ranging from 54 to 84 % (10 examples). The starting materials were obtained by sulfonylation of N-alkenylanilines with methyl (chlorosulfonyl)acetate and subsequent bromination. For the N-alkenylanilines (10 examples, 60–77 %
Oxidative Diamination of Alkenes with Ureas as Nitrogen Sources: Mechanistic Pathways in the Presence of a High Oxidation State Palladium Catalyst
作者:Kilian Muñiz、Claas H. Hövelmann、Jan Streuff
DOI:10.1021/ja075041a
日期:2008.1.1
identical mechanism where stereochemistry is concerned. It exemplifies the importance of cationic palladium(IV) intermediates prior to the final reductiveeliminationfrom palladium and proves that the nucelophile for this step stems from the immediate coordination sphere of the palladium(IV) precursor. These results have important implications for the general development of alkene 1,2-difunctionalization
Assisted tandem catalytic RCM-aromatization in the synthesis of pyrroles and furans
作者:Bernd Schmidt、Stefan Krehl、Eric Jablowski
DOI:10.1039/c2ob25543j
日期:——
An assisted tandem catalytic transformation of diallyl amines and diallyl ethers into N-aryl pyrroles and furans, respectively, is described. The sequence relies on ring closing metathesis followed by dehydrogenation of the initially formed dihydropyrroles and dihydrofurans. Both steps are Ru-catalyzed, but the sequence requires only one precatalyst, because conversion of the metathesis catalyst into