Stereodivergent Total Syntheses of (+)-Monomorine I and (+)-Indolizidine 195B

A simple and efficient stereoselective total syntheses of two natural products (+)-monomorine I and (+)-indolizidine 195B in high yields starting from a readily available alcohol is described. The key step in this synthetic route exploits the judicious use of solvent to enable a closed or open transition state in a nucleophilic addition of Grignard reagent to sulfinimine, giving selective access to two distinct diastereomers required for the formation of the two target natural products.

Automated summary

This method efficiently synthesizes two natural products (+)-monomorine I and (+)-indolizidine 195B in high yields from a readily available alcohol, with selective access to two distinct diastereomers through the judicious use of solvent in a nucleophilic addition reaction.