AI Article Synopsis
- New families of enantiopure bis(oxazolines) with distinct stereochemistry (4,5-trans and 4,5-cis) were synthesized with high efficiency.
- The trans oxazoline derivatives formed eta(3)-allyl palladium complexes that were effective in catalyzing allylic alkylation reactions with high enantioselectivity, reaching up to 96%.
- NMR studies revealed the presence of different isomer forms in the palladium intermediates, highlighting a novel case of isomerism in Pd allylic complexes with malonic acid-derived bis(oxazolines).
Article Abstract
New families of enantiopure bis(oxazolines) with 4,5-trans (5 a-g) or 4,5-cis (6 c) stereochemistry at the individual rings have been prepared in high yield. Their eta(3)-allyl palladium complexes (8 a-g, 9 c and 10) have been used as catalytic precursors in allylic alkylation reactions with excellent enantioselectivities (up to 96 %) for the trans oxazoline derivatives, while Pd/6 c system was inactive. NMR studies on palladium eta(3)-1,3-diphenylallyl intermediates (11 a, c and e) showed the presence of syn/syn- and syn/anti-allyl isomers in solution; this resembles the first example of eta(3)-eta(1)-eta(3) isomerism in Pd allylic complexes containing bis(oxazolines) derived from malonic acid.
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| http://dx.doi.org/10.1002/1521-3765(20020916)8:18<4164::AID-CHEM4164>3.0.CO;2-G | DOI Listing |
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