170438-03-6Relevant articles and documents
A practical synthesis of enantiopure (S)-4-(4-hydroxybenzyl)-oxazolidin-2-one
Green, Rachel,Taylor, Piers J. M.,Bull, Steven D.,James, Tony D.,Mahon, Mary F.,Merritt, Andy T.
, p. 2619 - 2623 (2003)
A high yielding four-step synthesis of enantiopure 4-(4-hydroxybenzyl)-oxazolidin-2-one (S)-1 from N-Boc-L-tyrosine is described. (S)-1 is a key intermediate for the preparation of a number of polymer supported Evans' oxazolidin-2-ones that have been employed previously for solid supported asymmetric synthesis.
Asymmetric solution-phase mixture aldol reaction using oligomeric ethylene glycol tagged chiral oxazolidinones
Turkyilmaz, Serhan,Wilcox, Craig S.
, p. 2031 - 2033 (2017/05/04)
Sorting tags are oligomeric structures that can be used as protecting groups or chiral auxiliaries enabling solution-phase mixture syntheses of multiple tagged compounds in one pot and allowing for facile and predictable chromatographic separation of products at the end of synthetic sequences. Perfluorinated hydrocarbon and oligomeric ethylene glycol (OEG) derivatives are known classes of sorting tags. Herein we describe the preparation of OEGylated chiral oxazolidinones and their use in asymmetric solution-phase mixture aldol reactions. Through the use of such oxazolidinones based on tyrosine four different individually tagged aldol adducts were obtained as a mixture, chromatographically demixed, detagged, and it was shown that these processes gave the desired aldol products in good yield and enantioselectivity.
N-Methylpyrrolidone Hydroperoxide/Cs2CO3 as an Excellent Reagent System for the Hydroxy-Directed Diastereoselective Epoxidation of Electron-Deficient Olefins
Victor, Napoleon John,Gana, Janardhanan,Muraleedharan, Kannoth Manheri
supporting information, p. 14742 - 14747 (2015/10/19)
This report introduces N-methylpyrrolidone hydroperoxide (NMPOOH)/base as an excellent reagent system for hydroxy-directed syn selective epoxidation of electron-deficient olefins, characterized by high diastereoselectivity, short reaction times and remarkable chemoselectivity, especially in presence of oxidatively labile nitrogen or sulfur atoms. NMPOOH also proves efficient in the oxidation of electron-deficient aromatic aldehydes, in the removal of oxazolidinone chiral auxiliary, and in the functionalization of alkenes and alkynes, showing wide application potential. Something kinda HOO-: This report introduces N-methylpyrrolidone hydroperoxide/base as an excellent system for the hydroxy-directed syn-selective epoxidation of electron-deficient olefins, characterized by high diastereoselectivity, short reaction times and remarkable chemoselectivity, especially in the presence of oxidatively labile nitrogen or sulfur atoms.
Rhodium-catalyzed borylation of aryl 2-pyridyl ethers through cleavage of the carbon-oxygen bond: Borylative removal of the directing group
Kinuta, Hirotaka,Tobisu, Mamoru,Chatani, Naoto
, p. 1593 - 1600 (2015/03/05)
The rhodium-catalyzed reaction of aryl 2-pyridyl ethers with a diboron reagent results in the formation of arylboronic acid derivatives via activation of the C(aryl)-O bonds. The straightforward synthesis of 1,2-disubstituted arenes was enabled through catalytic ortho C-H bond functionalization directed by the 2-pyridyloxy group followed by substitution of this group with a boryl group. Several control experiments revealed that the presence of a sp2 nitrogen atom at the 2-position of the substrate and the use of a boron-based reagent were crucial for the activation of the relatively inert C(aryl)-O bond of aryl 2-pyridyl ethers.
An Improved Preparation of Oxazolidin-2-one Chiral Auxiliaries
Sudharshan, Manjula,Hultin, Philip G.
, p. 171 - 172 (2007/10/03)
Reduction of carbamate-blocked amino esters by lithium borohydride (made in situ from sodium borohydride and lithium iodide) forms chiral 4-substituted oxazolidin-2-ones directly. The presence of iodide in the reaction mixture appears to promote the cyclization of the intermediate alkoxyborohydride. This provides a route to these important chiral auxiliaries, employing less hazardous reagents and simpler reaction conditions than do most existing methods.
Resin type can have important effects on solid phase asymmetric alkylation reactions
Burgess, Kevin,Lim, Dongyeol
, p. 785 - 786 (2007/10/03)
A new N-propionylated oxazolidinone 1 is prepared; asymmetric alkylations of this auxiliary proceed with varying yields and enantioselectivities when supported on Merrifield, Wang and TentaGel R PHB resins.
Synthesis of chiral α-substituted β-hydroxy acid derivatives on solid support
Purandare, Ashok V.,Natarajan, Sesha
, p. 8777 - 8780 (2007/10/03)
Enantioselective aldol condensation using solid supported chiral auxiliary was used for the synthesis of α-substituted-β-hydroxy acid and ester. The solid phase synthesis proceeded with high degree of enatioselectivity, as is observed in solution chemistry.
