**Helfried Neumann 1, Alexey G. Sergeev 2, Anke Spannenberg <sup>1</sup> and Matthias Beller 1,\***


Academic Editor: José Pérez Sestelo Received: 2 July 2020; Accepted: 24 July 2020; Published: 28 July 2020

**Abstract:** A flexible two-step, one-pot procedure was developed to synthesize 2-aryl propionic acids including the anti-inflammatory drugs naproxen and flurbiprofen. Optimal results were obtained in the presence of the novel ligand neoisopinocampheyldiphenylphosphine (NISPCPP) (**9**) which enabled the efficient sequential palladium-catalyzed Heck coupling of aryl bromides with ethylene and hydroxycarbonylation of the resulting styrenes to 2-aryl propionic acids. This cascade transformation leads with high regioselectivity to the desired products in good yields and avoids the need for additional purification steps.

**Keywords:** Heck reaction; styrene; methoxycarbonylation; profene; palladium
