Manganese(II) acetate-mediated double 2-hydroperoxyalkylations of barbituric acid and its derivatives

Abstract

The reactions of 1,1-disubstituted ethenes with barbituric acid and its derivatives in the presence of manganese(II) acetate and air yielded 5,5-bis(2-hydroperoxyalkyl)barbituric acids 3aa-ac and 3ba-ja in 62-99% yields. The structure of 3ab was determined by X-ray crystallography. The reaction of la and 2a was also effected by manganese(III) acetate (95%) and metallic manganese (92%), but in poor yield by cerium(IV) ammonium nitrate (50%). Treatment of 5,5-bis(2-hydroperoxy-2.2-diphenylethyl)-l,3-dimethylbarbituric acid (3aa) with perchloric acid gave 5,5-bis(benzoylmethyl)-1.3-dimethylbarbituric acid ( 6) and 5-(2-benzoylmethyl)-l,3-dimethyl-5-(2,2-diphenylethenyl)barbituric acid (7), in which phenyl migration took place. Reduction of 3aa with zinc powder in acetic acid or with triphenylphosphine in diethyl ether yielded 5,5-bis(2-hydroxy-2,2-diphenylethyI)-1.3-dimethylbarbituric acid (10), which was dehydrated to give a spirotetrahydropyran 11.

Mn(III)‐catalyzed Aerobic Oxidation of 3‐Alkyl‐4‐hydroxy‐1H‐pyrrol‐2(5H)‐ones in the Presence of 1,1‐Diarylethenes. Synthesis of Stable 8‐Aza‐1‐hydroxy‐2,3‐dioxabicyclo[4.3.0]nonan‐7‐one Framework

“…Therefore, the peroxy radical D must be reduced by the Mn(II) species, and the Mn(III) species should be regenerated, and thus, the catalytic cycle is completed as shown in Scheme . In addition, it was also reported that the formation of 1,2‐dioxan‐3‐ols could be possible using only Mn(OAc) 2 in air .…”

Ionic Liquids-Prompted Synthesis of Biologically Relevant Five- and Six-Membered Heterocyclic Skeletons

“…The synthesis of furopyrimidines has received a little attention in spite of their wide range of associated bioactivities including antimicrobial, antiviral, antimicotic, and antiplatelet [84][85][86]. Shaabani et al reported a three-component condensation reaction of N,N′-dimethylbarbituric acid with aldehydes and alkyl or aryl isocyanides at room temperature (RT) in the presence of [BMIM][Br] in a molar ratio of 1:1 (reactant/IL) to afford furo [2,3-d]pyrimidine-2,4(1H,3H)-diones 32 (Scheme 6).…”

Manganese(III) Acetate: A Versatile Reagent in Organic Chemistry

“…Recently, it was reported that Mn(OAc) 3 oxidation of alkenes with 1,2-disubstituted pyrazolidine-3,5-diones [44] and barbituric acid derivatives [45] did not give the expected bicyclic peroxides, whereas they gave the unexpected double 2-hydroperoxyalkylated products. The reason was believed to be due to the low reactivity of the carbamoyl groups towards this type of cyclization (Scheme 32).…”