Visible‐Light Mediated Photooxidative Phosphorylation of Benzylamines: A Novel and Mild Pathway Towards α‐Aminophosphorus Compounds

Abstract

Dedicated to Prof. E. Peter Kündig on his 75th birthdayTraditional syntheses of α-aminophosphorus therapeutic targets proceed through the hydrophosphorylation of C=N or C=O bonds, thus necessitating preliminary oxidized substrates. Cross-dehydrogenative coupling strategies can bypass this extra oxidation step by oxidizing simpler substrates in situ before phosphorylating them, but those protocols can suffer from the use of toxic stoichiometric oxidants. Photochemical strategies can access those oxidized intermediates without any harsh conditions and can use molecular oxygen as a benign and sustainable oxidant. We report herein a simple protocol using visible light, phosphinylidenes and benzylamine derivatives for the synthesis of α-aminophosphorus products under aerobic conditions and using an iridium photosensitizer.

Heterostructured PHI‐PTI/Li+Cl− Carbon Nitrides for Multiple Photocatalytic Applications

“…As a model reaction, aerobic oxidation of benzylamine to N ‐benzyl‐1‐phenylmethanimine was chosen; this process is a commonly used benchmark to test the oxidative power of photocatalysts [ 37 ] because the model substrate has a relatively accessible oxidation potential of +1.04 V versus SCE (+1.28 V versus SHE) in acetonitrile. [ 38 ] The materials were irradiated under oxygen atmosphere in an acetonitrile solution of benzylamine along with two previously described highly anionic catalysts, K‐PHI [ 39 ] and CN‐OA‐m, [ 40 ] used as references for comparison. The results of photocatalytic tests are shown in Figure a.…”

Phospha-Mannich reactions of phosphinous acids R 2 P–OH and their derivatives

“…P(O),NH-acetals, obtained by visible-light mediated reaction of benzylamines with Ph2P(O)H in the presence of an Ir complex. [197] S 101…”