# Diastereoselective Cyclopropanation with Secondary Diazoacetamides to Access endo-Azabicyclo[3.1.0]hexane-6-carboxamides

## TL;DR

This paper presents a new method to selectively create specific cyclopropane compounds using secondary diazoacetamides, which can be used to synthesize the drug Mazisotine.

## Contribution

A diastereoselective cyclopropanation method using secondary diazoacetamides to access endo-azabicyclohexane-6-carboxamides.

## Key findings

- The reaction works well for secondary diazoacetamides but not for tertiary amides.
- Base-mediated equilibration converts endo-isomers to exo-isomers.
- The method was successfully applied to synthesize the drug candidate Mazisotine.

## Abstract

A dirhodium­(II) tetracarboxylate-catalyzed reaction of
secondary
diazoacetamides with N-Boc-2,5-dihydro-1H-pyrrole results in a highly diastereoselective cyclopropanation
for the synthesis of endo-azabicyclo­[3.1.0]­hexane-6-carboxamides.
These reaction conditions work well for secondary diazoacetamides
but are not compatible with their tertiary amide counterparts. A base-mediated
equilibration of the endo-isomer allows access to
the exo-azabicyclo­[3.1.0]­hexane-6-carboxamides. The
utility of this cyclopropanation chemistry was illustrated by its
application to the synthesis of the drug candidate, Mazisotine.