247238-39-7Relevant academic research and scientific papers
Ruthenium-Catalyzed Enantioselective Addition of Carboxylic Acids to Allenes
Hu, Jiang-Lin,Bauer, Felix,Breit, Bernhard
, p. 12301 - 12306 (2021/10/12)
A ruthenium-catalyzed synthetic method for branched allylic esters via addition of carboxylic acids to allenes is reported. Ligands were designed and prepared based on the Josiphos skeleton, with which the reaction achieved up to 95% yield and up to >99% enantiomeric excess. A deuterium labeling experiment was performed and a plausible mechanism was proposed. Enantiopure lactones of five- and six-membered ring were synthesized via a RCM reaction of the branched allylic ester product.
Iridium-catalyzed kinetic asymmetric transformations of racemic allylic benzoates
Stanley, Levi M.,Bai, Chen,Ueda, Mitsuhiro,Hartwig, John F.
supporting information; experimental part, p. 8918 - 8920 (2010/08/21)
Versatile methods for iridium-catalyzed, kinetic asymmetric substitution of racemic, branched allylic esters are reported. These reactions occur with a variety of aliphatic, aryl, and heteroaryl allylic benzoates to form the corresponding allylic substitution products in high yields (74-96%) with good to excellent enantioselectivity (84-98% ee) with a scope that encompasses a range of anionic carbon and heteroatom nucleophiles. These kinetic asymmetric processes occur with distinct stereochemical courses for racemic aliphatic and aromatic allylic benzoates, and the high reactivity of branched allylic benzoates enables enantioselective allylic substitutions that are slow or poorly selective with linear allylic electrophiles.
Copper catalyzed asymmetric synthesis of chiral allylic esters
Geurts, Koen,Fletcher, Stephen P.,Feringa, Ben L.
, p. 15572 - 15573 (2007/10/03)
The complex derived from Taniaphos ligand 4 and CuBr?Me2S catalyzes the asymmetric addition of Grignard reagents to 3-bromopropenyl esters 1 to provide allylic esters 2 in high yields and high chemio-, regio-, and enantioselectivities. The work demonstrates that allylic asymmetric alkylation (AAA) can be done on substrates bearing a heteroatom at the γ-position. The method is a practical route to chiral, nonracemic allylic alcohols. The use of functionalized substrates 1 or Grignard reagents leads to more complex products 2, which can be further manipulated as demonstrated in conversion to (S)-5-ethyl-2(5H)-furanone 6 and (S)-benzoic acid-cyclopent-2-enyl ester 7. Copyright
