Asymmetric Cleavage of Racemic 1,3-Oxazolidines – A New Dynamic Process in Homogeneous Rh(I)-Catalyzed Hydrogenation
作者:Vitali I. Tararov、Renat Kadyrov、Axel Monsees、Thomas H. Riermeier、Armin Börner
DOI:10.1002/adsc.200390018
日期:2003.1
The mechanism of the homogeneously catalyzed hydrogenation of 1,3-oxazolidines with a Rh(I) diphosphane catalyst affording tertiary hydroxyethyl-substituted amines was investigated with the help of D2 labelling experiments. It was found that the reaction proceeds via prochiral intermediates with, preferentially, an iminium cation being in equilibrium with the 1,3-oxazolidine. This observation opened
Synthesis of N-(Dialkylaminoalkyl)alcohols by Homogeneously Catalyzed Hydrogenolysis of Cyclic N,O-Acetals
作者:Vitali I. Tararov、Renat Kadyrov、Thomas H. Riermeier、Armin Börner
DOI:10.1055/s-2002-20039
日期:——
The homogeneously catalyzed hydrogenation of 1,3-ox-azolidines affording unsymmetrically substituted 2-N-(dialkylamino)ethanols is reported showing for the first time that Rh(I) catalysts based on chelating diphosphines can be advantageous for this reaction.
A General Metal‐Free Protocol for the Visible‐Light‐Driven Protection of Carbonyls
作者:Lorenzo Di Terlizzi、Eirini M. Galathri、Stefano Protti、Christoforos G. Kokotos、Maurizio Fagnoni
DOI:10.1002/cssc.202201998
日期:2023.1.20
Carbonylprotection: This work highlights the potential of arylazo sulfones as non-ionic photoacid generators (PAGs) to promote the efficient conversion of aldehydes and ketones into acetals, ketals, and 1,3-oxazolidines upon visible-light irradiation. This approach takes advantage of the mild conditions employed and exhibits an easy scalability and a broad substrate scope (80 examples included).