New Concepts for Organocatalysis
17
Scheme 12. Brønsted acid-catalyzed Pictet–Spengler reaction
Seayad et al. 2006). Remarkably, the reaction tolerates a variety of different aldehydes with good results.
3.2
Organocatalytic Asymmetric Reductive Amination
The catalytic hydrogenation of alkenes, ketones, and imines is arguably
one of the most important transformations in chemistry. Powerful asymmetric versions have been realized that require metal catalysts or the