93553-66-3Relevant academic research and scientific papers
Regio- and stereospecific alkyl and alkynyl substitution reactions of epoxy selenides with organoaluminums via episelenonium ions
Sasaki, Minoru,Hatta, Mitsuru,Tanino, Keiji,Miyashita, Masaaki
, p. 1911 - 1913 (2004)
Regio- and stereospecific alkyl and alkynyl substitution reactions of epoxy selenides with organoaluminum reagents have been developed, which proceed via episelenonium ion intermediates to give the C2 alkyl substitution products with double inversion of t
Regio- And Enantioselective Iridium-Catalyzed Amination of Alkyl-Substituted Allylic Acetates with Secondary Amines
Jung, Woo-Ok,Yoo, Minjin,Migliozzi, Madyson M.,Zbieg, Jason R.,Stivala, Craig E.,Krische, Michael J.
supporting information, p. 441 - 445 (2021/12/27)
Robust air-stable cyclometalated π-allyliridium C,O-benzoates modified by (S)-tol-BINAP catalyze the reaction of secondary aliphatic amines with racemic alkyl-substituted allylic acetates to furnish products of allylic amination with high levels of enantioselectivity. Complete branched regioselectivities were observed despite the formation of more highly substituted C-N bonds.
Total Synthesis of the Echinodermatous Ganglioside LLG-3 Possessing the Biological Function of Promoting the Neurite Outgrowth
Huang, Yuahn-Sieh,Shih, Jing-Feng,Tsai, Yow-Fu,Wu, Yu-Fa
, p. 7491 - 7495 (2020/10/09)
A total synthesis of echinodermatous ganglioside LLG-3 with neuritogenic activity was accomplished by a convergent strategy. The synthesis of 2-hydroxyethyl 8-O-Me-α-sialoside 2 was started from the phenyl 7,8-di-O-Pico-thiosialoside 5, which can be chemoselectively removed the picoloyl group, and then the methyl group in 8-O-MeNeu5Ac moiety was chemoselectively prepared using TMSCHN2/FeCl3. For preparation of the terminal disialic unit, oxidative amidation was initially utilized by our group to efficiently construct the α(2,11) linkage of 8-O-Me-Neu5Acα(2,11)Neu5Gc. Herein, we also demonstrate that the synthesized ganglioside LLG-3 exhibited the neuritogenic activity toward the primary cortical neurons and that biological activity is superior to that of ganglioside DSG-A.
Alkenyl Exchange of Allylamines via Nickel(0)-Catalyzed C-C Bond Cleavage
Fan, Chao,Lv, Xin-Yang,Xiao, Li-Jun,Xie, Jian-Hua,Zhou, Qi-Lin
supporting information, p. 2889 - 2893 (2019/02/19)
A functional group exchange reaction between allylamines and alkenes via nickel-catalyzed C - C bond cleavage and formation was developed. This reaction provides a novel protocol, which does not require the use of unstable imine substrates, for the synthesis of allylamines, which are widely used in the production of fine chemicals, pharmaceuticals, and agrochemicals.
Copper(I)-Catalyzed Stereo- and Chemoselective Borylative Radical Cyclization of Alkyl Halides Bearing an Alkene Moiety
Iwamoto, Hiroaki,Akiyama, Sota,Hayama, Keiichi,Ito, Hajime
supporting information, p. 2614 - 2617 (2017/05/24)
The stereoselective borylative radical cyclization of alkyl halides containing an alkene moiety was developed using a copper(I)/diboron catalyst system. The optimized reaction conditions allowed us to control the chemoselectivity between the allylic substitution and the borylative radical cyclization. The borylation products were subsequently converted to highly functionalized organic compounds by derivatization of the newly formed C-B bond. This borylative radical cyclization offers a novel methodology for the stereoselective synthesis of various heterocyclic compounds.
Chirality induction and chiron approaches to enantioselective total synthesis of α-lipoic acid
Chavan, Subhash P.,Pawar, Kailash P.,Praveen, Ch.,Patil, Niteen B.
supporting information, p. 4213 - 4218 (2015/06/02)
Abstract An efficient, short and convenient asymmetric synthesis of (R)-(+)-lipoic acid in seven steps from chiral hydroxy aldehyde with 32.5% overall yield is described. Synthesis of S and R enantiomers of α-lipoic acid from cis-1,4-butene diol derived chiral lactone is reported with 34 % overall yield. The present synthesis involves use of simple reaction conditions making it a convenient synthesis.
Palladium-catalyzed selective anti-markovnikov oxidation of allylic esters
Dong, Jia Jia,Fananas-Mastral, Martin,Alsters, Paul L.,Browne, Wesley R.,Feringa, Ben L.
supporting information, p. 5561 - 5565 (2013/06/27)
An aldol alternative: The palladium(II)-catalyzed anti-Markovnikov oxidation of allylic esters to aldehydes at room temperature provides a viable alternative to valuable cross aldol products. High regioselectivity towards the aldehyde product was achieved using the ester protecting group for the allylic alcohol. Rapid isomerization and the much higher rate of oxidation of the branched isomer result in the same product forming from both linear and branched allylic esters. Copyright
Regio- and stereoretentive synthesis of branched, linear (E)- and (Z)-allyl fluorides from allyl carbonates under Ir-catalysis
Benedetto, Elena,Tredwell, Matthew,Hollingworth, Charlotte,Khotavivattana, Tanatorn,Brown, John M.,Gouverneur, Veronique
, p. 89 - 96 (2013/05/09)
This paper describes a new catalytic method for the regio- and stereocontrolled fluorination of allylic carbonates. This transformation uses TBAF·4tBuOH as the fluoride source and [Ir(COD)Cl]2 as the catalyst; the most commonly used [Ir(COD)Cl]2/phosphoramidite system is ineffective. Synthetically, this reaction is characterized by a high degree of structural conservation in going from substrates to the products. The fluorination of (E)-allylic carbonates leading to linear (E)-allylic fluorides (l : b > 20 : 1, E : Z > 20 : 1) is unprecedented and a unique feature of fluoride as the nucleophile. The first examples of transition metal catalyzed fluorination affording (Z)-allyl fluorides (Z : E ratio >20 : 1) are disclosed along with the successful fluorination of branched, linear (E)- and (Z)-allyl carbonates with [18F] fluoride in the presence of [Ir(COD)Cl]2. 18O-Labeling of the reactant reveals internal return during the allylic ionization step, and pathways for effective intra- and intermolecular isotope exchange.
α-Sulfonyl succinimides: Versatile sulfinate donors in Fe-catalyzed, salt-free, neutral allylic substitution
Jegelka, Markus,Plietker, Bernd
supporting information; experimental part, p. 10417 - 10430 (2011/10/31)
Allyl sulfones are versatile intermediates in organic chemistry. The presence of two distinct functional groups sets the stage for a plethora of subsequent transformations. However, despite these advantages the preparation of regioisomerically enriched sulfones is not easy. The use of sulfinate salts as nucleophiles in substitutions is frequently accompanied by side reactions such as π-bond migration, β-elimination, and so on. Herein we present a preparatively simple way to synthesize a variety of different aryl or alkyl allyl sulfones starting from readily accessible allylic carbonates. By employing aryl or alkyl α-sulfonyl succinimides as sulfinate synthons, mild and regioselective ipso substitution of diverse allylic carbonates was realized.
Ir-catalysed formation of C-F bonds. From allylic alcohols to α-fluoroketones
Ahlsten, Nanna,Martin-Matute, Belen
supporting information; experimental part, p. 8331 - 8333 (2011/09/12)
A novel iridium-catalysed tandem isomerisation/C-F bond formation from allylic alcohols and Selectfluor to prepare α-fluorinated ketones as single constitutional isomers is reported.
