# Total Syntheses of (±)-Lepadiformine B and C

## TL;DR

This paper describes the complete chemical synthesis of two compounds, lepadiformine B and C, using a stereodivergent approach.

## Contribution

The novel contribution is a stereodivergent synthesis method for N-acetyl-2-alkyl-8a-cyanodecahydroquinoline derivatives.

## Key findings

- A deprotection-initiated alkylative/reductive cyclization method was developed for stereodivergent synthesis.
- Lepadiformine B and analogs were synthesized via Ir-catalyzed reductive cyanation and other reactions.
- The method allows for the preparation of both cis- and trans- isomers efficiently.

## Abstract

Total syntheses of (±)-lepadiformine B and C are
presented.
The key theme in our approach is the stereodivergent synthesis of
both cis- and trans- N-acetyl-2-alkyl-8a-cyanodecahydroquinoline, which are effectively
prepared through deprotection-initiated alkylative/reductive cyclization
of sterically well-defined α-aminonitriles bearing a masked
carbonyl group. After the Dieckmann-type condensation to a tricyclic
lactam, lepadiformine B and its analogues can be achieved through
the Ir-catalyzed reductive cyanation and subsequent hydrolysis, reduction,
and Bruylants reactions.