Programmable enantioselective one-pot synthesis of molecules with eight stereocenters

Abstract

We developed an enantioselectively catalyzed tandem synthesis of structurally and stereochemically complex molecules that forms four carbon-carbon bonds and sets eight stereocenters with high regio-, diastereo- and enantioselectivity. It can be programmed to yield different stereoisomers by varying only the order of combination of a common set of reagents and catalysts. We report what is to our knowledge the first synthesis of both enantiomers of a chiral compound using the same chiral catalyst.

Multi-Bond Forming Processes in Efficient Synthesis

“…[22,146] Another interesting three component reaction using independent dipolar cycloadditions to benzoquinone (45) was recently disclosed by Waldmann and coworkers (Scheme 24). [147] Enantioselective [3þ2] cycloadditions are deployed in a two-directional sense to unite three components, forming up to eight stereocentres. Judicious modification of reaction conditions allowed the control of both chemo-and regioselectivity, which promises access to a wide range of related structures.…”

Synthesis and stability of cyclic α-hydrogen nitroxides

“…The quinone oxidation state of the product produced on standing could be verified from 13 C NMR signals for the C=O carbon at 182.4 and 181.9 ppm. 19 We had initially assigned the trans stereochemistry to this product based on the X-ray of 13a. 12 However, the X-ray analysis of 11c ( Figure 6) clearly showed that this cycloadduct had the 1-naphthyl and ester groups in a cis relationship.…”

Following the Lead from Nature: Divergent Pathways in Natural Product Synthesis and Diversity‐Oriented Synthesis

“…[109] This was achieved by engaging benzoquinone (162) in two subsequent dipolar cycloadditions with imines 163, followed by imines 164, in the presence of the phosphane catalyst 165. [109] This was achieved by engaging benzoquinone (162) in two subsequent dipolar cycloadditions with imines 163, followed by imines 164, in the presence of the phosphane catalyst 165.…”