First iron-catalyzed synthesis of oximes from styrenes

Abstract

Aryl-substituted olefins react with t-butyl nitrite and sodium borohydride in the presence of iron(ii)phthalocyanine to give oximes in moderate to high yields.

Iron‐Catalysed Reductive Cross‐Coupling of Alkenes

“…[4] Recently, the nitrosation of styrene derivatives to give oximes was demonstrated by using 1 mol % iron catalyst, sodium borohydride and tert-butyl nitrite as the nitrogen monoxide source. [5] Once again, an iron(III) alkyl species was proposed as an alkyl radical equivalent in the reaction, which was trapped by reaction with tert-butyl nitrite. Mukaiyama had previously reported the nitrosation of alkenes by using phenylsilane as the hydrogen source, rather than sodium borohydride, however in this case alkyl nitroso dimers were predominantly formed.…”

tert-Butyl Nitrite

“…9 (I) Aryl-substituted olefins reacted with TBN and sodium borohydride in the presence of iron(II) phthalocyanine [Fe(Pc)] to give oximes in moderate to high yields. 10 (J) Adding TBN to a solution of amine in DMF could result in deamination. The conversion from N-methyl-3-aminoindazoles into Nmethylindazoles was adapted from this procedure.…”

Iron Phthalocyanine

“…FePc is widely used in a variety of catalytic transformations, 1 including N-alkylation, 2 C-H amination, 3 C-C bond formation, 4 preparation of esters 5 and oximes, 6 reduction, 7 oxidation, 8,9 and radical reactions. 10 Although FePc is particularly studied as a catalyst for organic reactions, this particular reagent is also described in many other applications.…”

“…The treatment of substituted styrenes with tert-butyl nitrite and NaBH 4 in the presence of FePc affords oximes in moderate to high yields. 6 (F) Iron tetrasulfophthalocyanine (FePcS) catalyzes the reduction of nitrite (NO 2 -) by dithionite or sulfoxylate in aqueous alkaline solution. Interestingly, different products can be obtained depending on the choice of the reductant.…”