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Bisoxazoline Ligands (bisoxazoline + ligand)
Selected AbstractsEffects of Extended Aryl-Substituted Bisoxazoline Ligands in Asymmetric Synthesis , Efficient Synthesis and Application of 4,4,-Bis(1-Naphthyl)-, 4,4,-Bis(2-Naphthyl)- and 4,4,-Bis(9-Anthryl)-2,2,-isopropylidenebis(1,3-oxazolines)EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 23 2005Hester L. van Lingen Abstract The steric influence of extended aryl substituents on 2,2,-bis(1,3-oxazoline) ligands was investigated in a series of asymmetric catalytic reactions such as Mukaiyama aldol and Michael reactions, hetero-Diels,Alder processes, and allylic alkylation reactions. 4,4,-(2-Naphthyl)- and 4,4,-(9-anthryl)-substituted isopropylidene-bridged 2,2,-bis(1,3-oxazolines) were synthesized and their enantioselective and catalytic properties in combination with different metals evaluated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] The Synthesis and Application of Novel C2 -Symmetric Chiral N,N,O,O Bisoxazoline Ligands with a Ferrocene Backbone.CHEMINFORM, Issue 17 2007Genghong Hua Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Stereocontrolled anionic alternating copolymerization of ethylphenylketene with benzaldehyde by a bisoxazoline ligandJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2004Daisuke Nagai Abstract Anionic copolymerization of ethylphenylketene with benzaldehyde with butyllithium or diethylzinc as the initiator proceeded in a perfect 1:1 alternating manner to produce the corresponding polyester, whose repeating unit had two adjacent chiral centers. The relative stereochemistry between these two chiral centers was successfully controlled by the addition of (S,S)-(-)-2,2,-isopropylidenebis(4- tert -butyl-2-oxazoline), producing the corresponding polyester that had excellent diastereoselectivity (erythro -configuration : threo -configuration = 4:96). The diastereomeric ratio was determined by high-performance liquid chromatography analysis of the diol, which was obtained by reductive degradation of the polyester while maintaining the configuration of the repeating unit. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5384,5388, 2004 [source] Asymmetric aziridination of 1,3-dienes catalyzed by bisoxazoline-copper complexesCHIRALITY, Issue 8 2006Linge Ma Abstract The asymmetric aziridination of 1,3-dienes catalyzed by bisoxazoline-CuOTf complexes with PhINTs as a nitrene precursor has been achieved in moderate yields with up to >99:1 regioselectivity, up to >99% diastereoselectivity, and up to 80% enantioselectivity. ,,,,,,,-Unsaturated ketones usually produced cis -,,,-aziridinated products, while 1,4-diphenyl-1,3-butadiene afforded both of cis - and trans -aziridine derivatives as major products by the use of different bisoxazoline ligands. The configuration of cis -aziridine derivatives was proposed on the basis of the reaction mechanism. Chirality, 2006. © 2006 Wiley-Liss, Inc. [source] | ||||||||||