Enantioselective Synthesis of 1-Aryl-tetrahydroisoquinolines through Iridium Catalyzed Asymmetric Hydrogenation

Asymmetric hydrogenation of 1-aryl-3,4-dihydroisoquinolines using the [IrCODCl]₂/(<i>R</i>)-3,5-diMe-Synphos catalyst is reported. Under mild reaction conditions, this atom-economical process provides easy access to a variety of enantioenriched 1-aryl-1,2,3,4-tetrahydroisoquinoline derivatives, which are important pharmacophores found in several pharmaceutical drug candidates, in high yields and enantiomeric excesses up to 99% after a single crystallization

Palladium-Catalyzed Efficient Enantioselective Synthesis of Chiral Allenes: Steric and Electronic Effects of Ligands

Asymmetric synthesis of chiral allenes starting from prochiral substrates under mild reaction conditions promoted by Pd-SYNPHOS catalyst is reported. This protocol provides an efficient access to various enantioenriched aryl- and alkyl- substituted allenes, which are versatile building blocks of high utility to both organic and medicinal chemists, in excellent isolated yields (up to 96%) and high enatiomeric ratio values (up to 95:5). In addition, a comparative study using several <i>C</i>₂-symmetric atropisomeric diphosphine ligands revealed the overwhelming impact of the steric and electronic properties of the ligands for the catalytic efficiency of this process