Chloroform as a Carbon Monoxide Precursor: <i>In</i> or <i>Ex Situ</i> Generation of CO for Pd-Catalyzed Aminocarbonylations
作者:Samuel N. Gockel、Kami L. Hull
DOI:10.1021/acs.orglett.5b01385
日期:2015.7.2
Conditions for the rapid hydrolysis of chloroform to carbonmonoxide (CO) using heterogeneous CsOH·H2O are described. CO and 13CO can be generated cleanly and rapidly under mild conditions and can be captured either in or ex situ in palladium-catalyzedaminocarbonylationreactions. Utilizing only 1–3 equiv of CO allows for the aminocarbonylation of aryl, vinyl, and benzyl halides with a wide variety
Imino Glycals via Ruthenium-Catalyzed RCM and Isomerization
作者:Bernd Schmidt、Sylvia Hauke、Nino Mühlenberg
DOI:10.1055/s-0033-1338615
日期:——
enamides via a ruthenium-catalyzed assisted tandem catalytic ring-closing metathesis–isomerization sequence. The sequence relies on the in situ transformation of a metathesis active Ru–carbene into an isomerization active Ru–hydride by addition of hydroxide as a chemical trigger. N-Allyl-N-homoallylamines were converted in one step into cyclic enamides via a ruthenium-catalyzed assisted tandem catalytic
Synthesis of Cyclic
<i>N</i>
‐Hydroxylated Ureas and Oxazolidinone Oximes Enabled by Chemoselective Iodine(III)‐Mediated Radical or Cationic Cyclizations of Unsaturated
<i>N</i>
‐Alkoxyureas
作者:Laure Peilleron、Pascal Retailleau、Kevin Cariou
DOI:10.1002/adsc.201901135
日期:2019.11.19
In this study we describe the reactivity of unsaturated N‐alkoxyureas in the presence of different combinations of a hypervalent iodine(III) reagent and a bromide source or TEMPO. Three complementary cyclizations can be achieved depending on the reaction conditions. On the one hand, PIFA with pyridinium bromide leads to an oxybromination reaction. On the other hand, bis(tert‐butylcarbonyloxy)iodobenzene
Palladium-Catalyzed Stille-Type Coupling of <i>N</i>-Acyl Iminium Ions with Distannanes: A Multicomponent Synthesis of α-Amidostannanes
作者:Boran Xu、Bruce A. Arndtsen
DOI:10.1021/cs401164z
日期:2014.3.7
The palladium-catalyzed three-component coupling of imines, acid chlorides, and hexabutyldistannane is described. This results in the synthesis of various α-amidostannanes in good yields, without the use of strong nucleophilic organometallic reagents. The reaction is believed to proceed via a Stille-type cross coupling of an in situ-generated N-acyl iminium salt with Bu3SnSnBu3 and reaches completion
Palladium-Catalyzed Multicomponent Synthesis of 2-Imidazolines from Imines and Acid Chlorides
作者:Boran Xu、Kraig Worrall、Bruce Arndtsen
DOI:10.3390/molecules171213759
日期:——
We describe the palladium-catalyzed multicomponent synthesis of 2-imidazolines. This reaction proceeds via the coupling of imines, acid chlorides and carbon monoxide to form imidazolinium carboxylates, followed by a decarboxylation. Decarboxylation in CHCl(3) is found to result in a mixture of imidazolinium and imidazolium salts. However, the addition of benzoic acid suppresses aromatization, and generates