Photochemical reactions of chromium-alkoxycarbene complexes with stabilized ylides to produce push-pull captodative allenes
作者:Michael R. Sestrick、Michael Miller、Louis S. Hegedus
DOI:10.1021/ja00037a008
日期:1992.5
Photolysis of chromium alkoxycarbene complexes in the presence of stabilized ylides produced allenes having effect withdrawing groups on C-1 and electron donating groups on C-3. These highly reactive captodative allenes rearranged to 1,3-substituted-1,3-dienes under mildly acidic conditions and hydrolyzed to γ-ket-α,β-unsaturated esters, both in excellent yield
Addition of Bifunctional Organoboron Reagents to Strained Alkenes. Carbon−Carbon Bond Formation with Rh(I) Catalysis in Aqueous Media
作者:Mark Lautens、John Mancuso
DOI:10.1021/jo049874k
日期:2004.5.1
complex to generate a functionalized organorhodium intermediate that can cyclize onto strained olefins in good to excellent yields. The catalytic system involves the use of an electron-rich, sterically bulky ligand to stabilize the organorhodium intermediate and reduce the incidence of protodeboronation in aqueous media.
Phosphonium-Iodonium Ylides with Heteroatomic Groups in the Synthesis of Annelated P-Containing Heterocycles
作者:Elena D. Matveeva、Tatyana A. Podrugina、Marina A. Taranova、Dmitriy S. Vinogradov、Rolf Gleiter、Nikolay S. Zefirov
DOI:10.1021/jo401514d
日期:2013.12.6
These compounds with three different heteroatoms attached to a negatively charged C atom represent potentially useful reagents that combine in one molecule the synthetic advantages of a phosphonium ylide and an iodonium salt. Specifically, they can react with a number of acetylenes, leading to hitherto unknown sulfonyl- and phosphoryl-substituted phosphinolines, phosphininothiophenes, and a novel type
Application of Germyldesulfonylation Reactions to the Synthesis of Germanium-Containing Nucleoside Analogues
作者:Stanislaw F. Wnuk、Pablo R. Sacasa、Jorge Restrepo
DOI:10.1080/15257770903054340
日期:2009.8.11
adenosine derivatives with tributyl- or triphenylgermane hydride (AIBN/toluene/Δ) effected radical-mediated germyldesulfonylations to give 5′-(tributyl- or triphenylgermyl)methylene-5′-deoxyuridine and adenosine derivatives as single (E)-isomers. Analogous treatment of 2′-deoxy-2′-[(phenylsulfonyl)methylene]uridine with Ph3GeH afforded the corresponding vinyl triphenylgermane product. Stereoselective halodegermylation
(E)-1-Alkyl-4-[2-(alkylsulfonyl)-1-ethenyl]pyridinium Salts: Reaction with Thiol Groups Giving Rise to Chromophoric (E)-1-Alkyl-4-[2-(alkylsulfanyl)-1-ethenyl]pyridinium Salts
作者:Michel Holler、Hong Sig Sin、Antony James、Alain Burger、Denis Tritsch、Jean-François Biellmann
-ethenyl]pyridinium iodide, prepared from the corresponding thioether by reaction with methyliodide in diethyl ether, underwent isomerization to the E isomer in a first-order reaction in deuterated [D6]DMSO with an activation energy of 14 kcalmol(-1). At pH 7, the (E)-1-methyl-4-[2-(methylsulfonyl)-1-ethenyl]pyridinium iodide (19) reacted specifically with thiols. The reaction of this sulfone with