Stoichiometric aerobic aminohydroxylation of ethylene mediated by dpms–platinum complexes (dmps = di(2-pyridyl)methanesulfonate)

Chloro di(2-pyridyl)methanesulfonate ethylene platinum(II) complex was converted to corresponding N-alkylplatina(II)azetidines by reacting the former with primary amines, MeNH2 and tert-BuNH2, to produce 2-ammonioethyl chloro platinum(II) species and their subsequent cyclization in the presence of NaOH in methanol. The N-alkylplatina(II)azetidines are oxidized under air or the atmosphere of pure O2 to the corresponding N-alkylplatina(IV)azetidines in water or in methanol solution in the presence of one equivalent of a strong acid under ambient pressure at 22 °C. The resulting N-alkylplatina(IV)azetidines undergo C–O reductive elimination in acidic aqueous solutions to produce 2-(N-alkylamino)ethanols.

N-alkylplatina(II)azetidines (alkyl = Me, tert-Bu) were prepared from chloro di(2-pyridyl)methanesulfonate ethylene platinum(II) complex and corresponding alkylamine. These complexes react with O2 to form the corresponding N-alkylplatina(IV)azetidines in water at 20 °C; the latter complexes undergo C-O reductive elimination in acidic aqueous solutions to produce 2-(N-alkylamino)ethanols in high yield.Figure optionsDownload as PowerPoint slideResearch highlights
► Stoichiometric aminohydroxylation of coordinated ethylene in the presence of primary amines and dioxygen as a direct oxidant is achieved using di(2-pyridyl)methanesulfonate Pt(II) complexes in acidic aqueous solutions
► Di(2-pyridyl)methanesulfonate ligand enables aerobic oxidation of N-alkylplatina(II)azetidines to N-alkylplatina(IV)azetidines in acidic aqueous media.
► N-alkylplatina(IV)azetidines undergo C–O reductive elimination in acidic aqueous solutions to form 2-(N-alkylamino)ethanol-derived salts.
► C–N reductive elimination of N-alkylplatina(IV)azetidines is not observed in either aprotic or protic solvents.