Solid Supported Chiral <i>N</i>
-Picolylimidazolidinones: Recyclable Catalysts for the Enantioselective, Metal- and Hydrogen-Free Reduction of Imines in Batch and in Flow Mode
organocatalysts for the catalytic reduction of imines with trichlorosilane has been developed. Polystyrene proved to be a more effective support than silica in terms of both chemical and stereochemical efficiency. Even with a loading as low as 1 mol% the best performing supported catalyst showed a remarkable activity and stereocontrol ability, promoting the reduction with stereoselectivities reaching 98% ee and
A new class of chiral Lewis bases for the enantioselective HSiCl3‐mediated reduction of imines was developed. Through extensive catalyst structure optimization, an extremely active species was identified that was able to promote the reduction of a large variety of functionalized substrates in high yields with enantioselectivities typically above 90 % with catalyst loadings as low as 0.1–1 mol %. The
Enantiomericallypure chiral amines are of increasing importance and commercial value in the fine chemical, pharmaceutical, and agrochemical industries. Here, we describe the straightforward synthesis of chiral amines by combining the atom‐economic and environmentally friendly hydroamination of alkynes with an enantioselective hydrogenation of in situ generated imines by using inexpensive hydrogen
Chiral phosphoric acids are incorporated into indium-based metal-organicframeworks (In-MOFs) by sterically preventing them from coordination. This concept leads to the synthesis of three chiral porous 3D In-MOFs with different network topologies constructed from three enantiopure 1,1'-biphenol-phosphoric acid derived tetracarboxylate linkers. More importantly, all the uncoordinated phosphoric acid
stereoselectivity. The applicability of the solid-supported catalyst of choice to the reduction of different imines was also demonstrated. Additionally, for the first time, a catalytic reactor containing a polymer-immobilized chiral picolinamide has been employed for the stereoselectivereduction of imines with trichlorosilane under continuous flow conditions.