40145-08-2Relevant academic research and scientific papers
Stereoselective desymmetrizations of dinitriles to synthesize lactones
Kelley, Amber M.,Frost, Joshua A.,Baber, Tylisha M.,Youngblood, Kala C.,Michishita, Emiri,Bain, Schuyler A.,Caleb Lykins,Petersen, Kimberly S.
supporting information, (2021/12/17)
Nitriles are important organic functional groups, allowing for installation of nitrogen in organic synthesis. The Pinner reaction transforms nitriles into esters via the imidate group, but in general has previously necessitated harsh acid conditions. This
Nickel-Catalyzed Asymmetric Kumada Cross-Coupling of Symmetric Cyclic Sulfates
Eno, Meredith S.,Lu, Alexander,Morken, James P.
, p. 7824 - 7827 (2016/07/11)
Nickel-catalyzed enantioselective cross-couplings between symmetric cyclic sulfates and aromatic Grignard reagents are described. These reactions are effective with a broad range of substituted cyclic sulfates and deliver products with asymmetric tertiary carbon centers. Mechanistic experiments point to a stereoinvertive SN2-like oxidative addition of a nickel complex to the electrophilic substrate.
Synthesis of the major metabolites of febuxostat
Li, Xiao Long,Qiu, Rui,Wan, Wei Li,Cheng, Xu,Hai, Li,Wu, Yong
, p. 217 - 221 (2015/06/23)
Total synthesis of three Febuxostat metabolites, named 67M-1, 67M-2, and 67M-4,is described in this article. Through condensation of the key intermediate compound A with different side chains, and then oxidation and hydrolysis, we obtained three target compounds with an overall yield of 19.5%-28.0%.
A scalable, Nonenzymatic synthesis of highly stereopure difunctional C4 secondary methyl linchpin synthons
Mekala, Shekar,Hahn, Roger C.
, p. 1610 - 1617 (2015/02/19)
In response to the continuing widespread use of heterodifunctional C4 secondary methyl building blocks in asymmetric synthesis, we have developed a mole-scale, two-step synthesis of a 1:1 mixture of the diastereomers of 3-bromo-2-methyl-1-propyl camphorsulfonate (casylate). One isomer (2S) has been crystallized to >99:1 dr in ～25% yield. Equilibration of the mother liquor (enriched in 2R) to a 1:1 mixture and recrystallization significantly raises the overall yield of 2S. Applications of 2S include chemoselective Grignard coupling, enabling the very short synthesis of highly stereopure long-chain natural products containing remote, methyl-bearing stereogenic centers [e.g., (R)-tuberculostearic acid], with complete control of configuration. Also, Ag-mediated, completely chemoselective Br displacement from 2S leads to a range of >99:1 er difunctional synthons. Both applications incorporate concurrent recovery of CasO. The enantiomer of 2S can be made from commercial (1R)-10-CasOH.
Synthesis of optically active β- Or γ-alkyl-substituted alcohols through copper-catalyzed asymmetric allylic alkylation with organolithium reagents
Guduguntla, Sureshbabu,Fananas-Mastral, Martin,Feringa, Ben L.
, p. 8274 - 8280 (2013/09/24)
An efficient one-pot synthesis of optically active β-alkyl-substituted alcohols through a tandem copper-catalyzed asymmetric allylic alkylation (AAA) with organolithium reagents and reductive ozonolysis is presented. Furthermore, hydroboration-oxidation following the Cu-catalyzed AAA leads to the corresponding homochiral γ-alkyl-substituted alcohols.
Haloalkane dehalogenase catalysed desymmetrisation and tandem kinetic resolution for the preparation of chiral haloalcohols
Westerbeek, Alja,Van Leeuwen, Jan G.E.,Szymański, Wiktor,Feringa, Ben L.,Janssen, Dick B.
experimental part, p. 7645 - 7650 (2012/09/21)
Six different bacterial haloalkane dehalogenases were recombinantly produced in Escherichia coli, purified, and used to catalyse the conversion of prochiral short-chain dihaloalkanes and a meso dihaloalkane, yielding enantioenriched haloalcohols. A two-reaction one-enzyme process was established in which the desymmetrisation of a dihaloalkane is followed by kinetic resolution of the chiral haloalcohol that is produced in the first step. In case of 1,3-dibromo-2-methylpropane and 1,3-dibromo-2-phenylpropane, an increase of the enantiomeric excess of the respective haloalcohol was observed in time, leading to ee values of >97%, with analytical yields of 24 and 52%, respectively. The results show that haloalkane dehalogenases can be used for the production of highly enantioenriched haloalcohols and that in some cases product enantiopurity can be improved by allowing a two-step one-enzyme tandem reaction.
Microwave thermolysis V : A rapid and selective method for the cleavage of THP ethers, acetals and acetonides using clay supported ammonium nitrate 'Clayan' in dry media
Meshram,Sumithra,Reddy,Ganesh,Yadav
, p. 2807 - 2815 (2007/10/03)
The deprotection of a variety of tetrahydropyranyl ethers (THP), acetonides and acetals into their parent compounds using clay supported ammonium nitrate 'Clayan' under microwave irradiation is described. The ecofriendly nature of the reagent and non solvent conditions are the important features of the procedure.
Ethyl phenylsulfinyl fluoroacetate, a new and versatile reagent for the preparation of α-fluoro-α,β-unsaturated carboxylic acid esters
Allmendinger, Thomas
, p. 4905 - 4914 (2007/10/02)
The title compound 2 can be alkylated with a wide range of alkyl halides and Michael acceptors. Subsequent thermal elimination of phenyl sulfinic acid 3 leads to α-fluoro-α,β-unsaturated ethyl carboxylates 5 and 10, an important class of intermediates for fluorine containing biologically active compounds.
