The efficient and novel bifunctional organocatalyst for the enantioselective aza-Morita-Baylis-Hillman (aza-MBH) reaction has been established with (S)-3-(N-isopropyl-N-3-pyridinylaminomethyl)BINOL for the first time. The reaction proved to be deeply influenced by the position of the Lewis base attached to BINOL. The acid-base-mediated functionalities for the activation of the substrate and the fixing of conformation of the organocatalyst are harmoniously performed to promote the reaction with high enantiocontrol.

No abstract

Stereospecific substitutions of optically pure 1-(pyridinyl)ethyl methanesulfonates with various amines are described. The reaction of (R)- or (S)-1-(2-pyridinyl)ethyl methanesulfonate with primary amines, including amino acid esters, gives N-substituted (S)- or (R)-1-(2-pyridinyl)ethylamines (4) with inversion of the configuration. Secondary cyclic amines are also reacted with (R)-2 to give the corresponding substituted amines (5) in excellent yields. Optically pure and meso triamine ligands having two pyridine rings, (S,S)-4f and meso-4f, (S,S)-9e, (S,R)-9e, and (S,S)-9f, have been prepared in stereochemically pure form by this method. Not only the substitution reaction of optically active 2 but also that of 1-(4-pyridinyl)ethyl and 1-(3-pyridinyl)ethyl methanesulfonates 11 and 14 take place stereospecifcally with inversion of the chiral center.

No abstract

No abstract

No abstract

Powerful bifunctional organocatalysts, (S)-3-(N-isopropyl-N-3-pyridinylaminomethyl) BINOL

Leave this area blank for abstract info. Tetrahedron: Asymmetry 3 Lewis base unit Bronsted acid units OH OH N N Bn 1lAbstract-The 1,3-propanediamine introduced onto the 3-position of (S)-BINOL through a methylene spacer could work as a chiral bifunctional organocatalyst for the aza-MBH reaction. The organocatalyst 1l effected the aza-MBH transformation with high chemical yields and up to 82% ee.