Resumen: The treatment of diethyl α,β‐dehydroaminophosphonate 1 with various arenes (ArH=toluene 2 a, benzene 2 b, anisole 2 c, bromobenzene 2 d, chlorobenzene 2 e, benzyl alcohol 2 f, p‐xylene 2 g) in acetic acid (AcOH) at 120 °C for 8 h in the presence of Pd(OAc)2 (10 % mol, OAc=acetate) and AgOAc (3.4 equivalents) results in the formation of the corresponding β‐aryl derivatives E‐Ar(H)C=C(NHAc)P(O)(OEt)2 3 a–3 g. The reaction proceeds through double C−H activation (arene and alkene) and subsequent C−C oxidative coupling (Fujiwara–Moritani reaction), processes catalyzed by Pd and assisted by Ag. The obtained products 3 a–3 g are isosteric analogs of phenylalanine and are obtained with high selectivity. Thus, geometrical E‐isomers have been obtained in all studied cases, however mixtures of ortho‐/meta‐/para‐isomers are observed when the activated position in the starting arene 2 is considered. Idioma: Inglés DOI: 10.1002/ejoc.202400146 Año: 2024 Publicado en: European Journal of Organic Chemistry 27, 18 (2024), e202400146 [6 p.] ISSN: 1434-193X Factor impacto JCR: 2.7 (2024) Categ. JCR: CHEMISTRY, ORGANIC rank: 16 / 57 = 0.281 (2024) - Q2 - T1 Factor impacto CITESCORE: 4.3 - Organic Chemistry (Q2) - Physical and Theoretical Chemistry (Q3)