Review of Calixarene-Derivatives in Transition Metal Chemistry

Abstract

The survey depicts the combination of large-scale monodentate phosphites in response to PCl3/NEt3 with p-tert-butyl calix[4]-(OH)3-OR, where R contains an oxygen-containing substituent (R = CH2P(O)Ph2, -CH2CO2Et, -CH2C(O)NEt2, -CH2CH2OMe). These funnel-shaped calissarenes have a phosphorus particle bridging three phenolic oxygen atoms, and are incredibly steady in NaOH-aqueous arrangement due to the cone point being more noteworthy than 180°. Upon response with transition metal particles, these phosphites shape either P monodentate complexes or expansive P,O chelate complexes including the oxygen atom of the R group. The reactivity of four different ligands in the rhodium-catalyzed hydroformylation of octene was examined. The general trend is that a bulkier phosphite ligand leads to a slower reaction rate. The ligand-to-base ratios ranged from 1.4 to 3.6, and the highest straight aldehyde selectivity was observed when the carboxylate group was CH2CO2Et.