# Palladium [ t‑Bu(PCP)PdOH] Pincer Complex as a Catalyst in the Michael Reaction

## TL;DR

A palladium pincer complex is shown to efficiently catalyze the Michael reaction, forming carbon–carbon bonds under mild conditions with high yields.

## Contribution

The isolation and structural characterization of a reactive palladium intermediate in the Michael reaction is novel.

## Key findings

- The [t-Bu(PCP)Pd(acac)] complex was isolated and characterized by X-ray diffraction.
- The catalyst provides Michael adducts in high yields (87–98%) under mild conditions.
- The reaction requires low catalyst loading, short times, and minimal solvent.

## Abstract

The Michael reaction is a versatile carbon–carbon
bond-forming
strategy that is efficiently catalyzed by transition metal complexes.
We report that the palladium [
t‑Bu(PCP)­PdOH] pincer complex effectively activates substrates and forms
stable complexes with ketones. The reactive intermediate [
t‑Bu(PCP)­Pd­(acac)] complex, which is formed in situ from acetylacetone and the [
t‑Bu(PCP)­PdOH] complex, was successfully isolated and structurally
characterized by single-crystal X-ray diffraction. This complex serves
as an active catalyst in the reaction between acetylacetone and various trans-nitrostyrenes, providing the corresponding Michael
adducts in high isolated yields (87–98%). The reaction proceeds
under mild conditions with a low catalyst loading, short reaction
times, and often minimal or no solvent. These results show that PCP-palladium
pincer complexes can serve as efficient, practical catalysts for C–C
bond-forming condensation reactions.