# Flash Communication: Probing Fe Complex Assembly via Thermogravimetric Analysis

## TL;DR

This paper shows how thermogravimetric analysis can help understand the formation of iron-based catalysts and improve reaction outcomes in synthetic chemistry.

## Contribution

The study introduces TGA as a novel method to evaluate Fe complex assembly and its impact on catalytic performance.

## Key findings

- TGA identified distinct Fe complexes formed from FeCl3 and dpa in different solvents.
- TGA profiles correlated with reaction yields in the methionine and benzyl acrylate reaction.
- Similar TGA profiles led to similar yields, while distinct profiles produced unique yields.

## Abstract

First-row transition metal catalysis continues to provide
innovative
and sustainable advances for synthetic chemistry. However, these metals
can be challenging to screen efficiently in optimization campaigns
due to the limited knowledge of catalyst assembly, stability, and
speciation. In this report we demonstrate the use of thermogravimetric
analysis (TGA) as a promising tool in evaluating the formation and
properties of an Fe precatalyst, fac-Fe­(dpa)­Cl3. Using TGA it was possible to identify the generation of
distinct Fe complexes that could form in situ from
prestirring the commercial metal salt iron trichloride (FeCl3) and di­(2-picolyl)­amine (dpa) in different organic solvents. Upon
applying these prestirred mixtures to the reaction between methionine
and benzyl acrylate, it was determined that distinct complexes gave
distinct TGA profiles. Similar TGA profiles yielded similar reaction
yields, while distinct TGA profiles tended to give rise to unique
yields. Utilizing this approach, a more informed first-row metal catalyzed
reaction strategy can be realized.