Up-scale pseudo-telescopic photo-induced Arndt-Eistert α-amino acids homologation in flow reactors cascade

We present an efficient, pseudo-telescopic synthesis of β-amino acids via the Arndt Eistert homologation of α-amino acids using flow reactors cascade. Our system utilizes flow generation of diazomethane, diazoketone preparation, and subsequent photo-flow Wolff rearrangement without intermediate isolation. This innovative method enhances safety, improves scalability, and allows access to substrates previously unavailable in the thermal/catalytic Wolff rearrangement. Notably, the reaction conditions are mild, which leads to high yields and excellent purity, thereby expanding the synthetic utility of the Wolff rearrangement. This work unveils a versatile and scalable approach in β-amino acid synthesis, opening new avenues in synthetic and medicinal chemistry.