29193-72-4Relevant academic research and scientific papers
A Giese reaction for electron-rich alkenes
Huang, Qi,Suravarapu, Sankar Rao,Renaud, Philippe
, p. 2225 - 2230 (2021/02/27)
A general method for the hydroalkylation of electron-rich terminal and non-terminal alkenes such as enol esters, alkenyl sulfides, enol ethers, silyl enol ethers, enamides and enecarbamates has been developed. The reactions are carried out at room temperature under air initiation in the presence of triethylborane acting as a chain transfer reagent and 4-tert-butylcatechol (TBC) as a source of hydrogen atom. The efficacy of the reaction is best explained by very favorable polar effects supporting the chain process and minimizing undesired polar reactions. The stereoselective hydroalkylation of chiralN-(alk-1-en-1-yl)oxazolidin-2-ones takes place with good to excellent diastereocontrol.
Radical-Mediated Strategies for the Functionalization of Alkenes with Diazo Compounds
Su, Yong-Liang,Liu, Geng-Xin,Liu, Jun-Wen,Tram, Linh,Qiu, Huang,Doyle, Michael P.
supporting information, p. 13846 - 13855 (2020/09/21)
One of the most common reactions of diazo compounds with alkenes is cyclopropanation, which occurs through metal carbene or free carbene intermediates. Alternative functionalization of alkenes with diazo compounds is limited, and a methodology for the addition of the elements of Z-CHR2 (with Z = H or heteroatom, and CHR2 originates from N2 CR2) across a carbon-carbon double bond has not been reported. Here we report a novel reaction of diazo compounds utilizing a radical-mediated addition strategy to achieve difunctionalization of diverse alkenes. Diazo compounds are transformed to carbon radicals with a photocatalyst or an iron catalyst through PCET processes. The carbon radical selectively adds to diverse alkenes, delivering new carbon radical species, and then forms products through hydroalkylation by thiol-assisted hydrogen atom transfer (HAT), or forms azidoalkylation products through an iron catalytic cycle. These two processes are highly complementary, proceed under mild reaction conditions, and show high functional group tolerance. Furthermore, both transformations are successfully performed on a gram-scale, and diverse γ-amino esters, γ-amino alcohols, and complex spirolactams are easily prepared with commercially available reagents. Mechanistic studies reveal the plausible pathways that link the two processes and explain the unique advantages of each.
From Alkyl Halides to Ketones: Nickel-Catalyzed Reductive Carbonylation Utilizing Ethyl Chloroformate as the Carbonyl Source
Shi, Renyi,Hu, Xile
supporting information, p. 7454 - 7458 (2019/04/30)
Ketones are an important class of molecules in synthetic and medicinal chemistry. Rapid and modular synthesis of ketones remains in high demand. Described here is a nickel-catalyzed three-component reductive carbonylation method for the synthesis of dialkyl ketones. A wide range of both symmetric and asymmetric dialkyl ketones can be accessed from alkyl halides and a safe CO source, ethyl chloroformate. The approach offers complementary substrate scope to existing carbonylation methods while avoiding the use of either toxic CO or metal carbonyl reagents.
Regioselective Alkoxycarbonylation of Allyl Phenyl Ethers Catalyzed by Pd/dppb under Syngas Conditions
Amézquita-Valencia, Manuel,Alper, Howard
, p. 3860 - 3867 (2016/05/24)
A simple and regioselective synthesis of phenoxy esters and phenylthio esters is reported. The products are obtained by selective alkoxycarbonylation catalyzed by Pd2(dba)3, 1,4-bis(diphenylphisphino)butane (dppb), and syngas (CO/H2) in chloroform/alcohol. This methodology affords bifunctional products in good yield with excellent n-selectivity and without the need to use additives.
Cobalt(i)-catalysed CH-alkylation of terminal olefins, and beyond
Giedyk, Maciej,Goliszewska, Katarzyna,ó Proinsias, Keith,Gryko, Dorota
supporting information, p. 1389 - 1392 (2016/01/25)
Cobalester, a natural nontoxic vitamin B12 derivative, was found to catalyse unusual olefinic sp2 C-H alkylation with diazo reagents as a carbene source instead of the expected cyclopropanation.
Preparation and reactivity of polyfunctional zinc and copper organometallics bearing sulfur functionalities
Achyutha Rao,Chou, Tso-Sheng,Schipor, Ioana,Knochel, Paul
, p. 2025 - 2043 (2007/10/02)
Iodomethylthiobenzoate 5 and α-chloroalkyl phenyl sulfides 6 were found to insert zinc dust in THF under very mild conditions (10-25°C, 0.5-2 h) leading to zinc α-thioorganometallics. After a transmetallation with CuCN·2 LiCl, the corresponding copper rea
Benzophenone Dicarboxylic Acid Antagonists of Leukotriene B4. 2. Structure-Activity Relationships of the Lipophilic Side Chain
Gapinski, D. Mark,Mallett, Barbara E.,Froelich, Larry L.,Jackson, William T.
, p. 2807 - 2813 (2007/10/02)
A series of lipophilic benzophenone dicarboxylic acid derivatives were found to inhibit the binding of the potent chemotoxin leukotriene B4 (LTB4) to its receptor on intact human neutrophils.Activity at the LTB4 receptor was determined by using a 3H>LTB4-binding assay.The structure-activity relationship for the lipophilic side chain was systematically investigated.Compounds with n-alkyl side chains of varying lengths were prepared and tested.Best inhibition of 3H>LTB4 binding was observed with the n-decyl derivative.Analogues with alkyl chains terminated with an aromatic ring showed improved activity.The 6-phenylhexyl side chain was optimal.Substitution on the terminal aromatic ring was also evaluated.Methoxyl, methylsulfinyl, and methyl substituents greatly enhanced the activity of the compound.For a given substituent, the para isomer had the best activity.Thus the nature of the lipophilic side chain can greatly influence the ability of the compounds to inhibit the binding of LTB4 to its receptor on intact human neutrophils.The most active compound from this series, 84 (LY223982), bound to the LTB4 receptor with the affinity approaching that of the agonist.
IONIC DENITROHYDROGENATION OF α-NITRO OR β-NITRO SULFIDES WITH TRIETHYLSILANE
Ono, Noboru,Hashimoto, Toshihiro,Jun, Tuo Xiao,Kaji, Aritsune
, p. 2277 - 2280 (2007/10/02)
The nitro groups of α-nitro or β-nitro sulfides are replaced by hydrogen on treatment with triethylsilane in the presence of Lewis acid.
