Manganese(III)-mediated oxidative free-radical additions of 1,3-dicarbonyl compounds to homobenzonorbornadiene and benzobarrelene: mechanistic studies

Ali, Mohamed Fadelalla
Caliskan, Rasit Ali
ŞAHİN, Ertan
Balcı, Metin
Homobenzonorbornadiene and benzobarrelene were reacted with dimedone/acetylacetone and Mn(OAc)(3) in the presence of Cu(OAc)(2) in acetic acid. Mainly rearranged products having a [2.2.2]skeleton and the nonrearranged dihydrofuran derivatives were obtained. These observations clearly indicated that the second oxidation takes place before the cyclization reaction. Furthermore, intramolecular tandem oxidations were observed where unusually oxyl radicals attack the double bond to form the products. The mechanism of the formation of the products is discussed.


Unusual manganese(III)-mediated oxidative free-radical additions of Meldrum's acid and dimethyl malonate to benzonorbornadiene and oxabenzonorbornadiene
ÇALIŞKAN, Raşit; Nohut, Neslihan; Yilimaz, Ozlem; ŞAHİN, Ertan; Balcı, Metin (Elsevier BV, 2017-01-26)
Benzonorbornadiene and 7-oxabenzonorbornadiene were reacted with Meldrum's acid and dimethyl malonate in the presence of Mn(OAc)(3) and Cu(OAc)(2) in acetic acid. The reaction of benzonorbornadiene with Meldrum's acid gave a naphthalene derivative whereas the reaction with dimethyl malonate formed rearranged products derived from a carbocation intermediate. However, the reaction of 7-oxabenzonorbornadiene with Meldrum's acid gave two nonrearranged products. On the other hand, the reaction with dimethyl malo...
Manganese(III) acetate-mediated synthesis of biaryls under microwave irradiation
Demir, Ayhan Sıtkı; Findik, Hamide; SAYGILI, NEZİRE; Subasi, N. Tuna (Elsevier BV, 2010-02-06)
Manganese(Ill) acetate (Mn(OAc)(3))-mediated synthesis of biaryls and heterobiaryls starting from arylboronic acid was developed under microwave irradiation in high yields Microwaves were also used for the synthesis of Mn(OAc)(3) from KMnO4 and acetic acid Additional irradiation of this in situ generated Mn(OAc)3 with arylboronic acids, which in turn furnished the biaryls in high yields In a one pot reaction This IS superior from the point of view of yield, short reaction time, sensitive functional group to...
Manganese(III) acetate based tandem oxidation of various α and β-alkoxy α,β-unsaturated ketones
Tanyeli, Cihangir; Sezen, Bengü (Elsevier BV, 2002-12-09)
We described the unusual results of manganese(III) acetate based tandem oxidation of various alpha and beta-alkoxy alpha,beta-unsaturated ketones to afford the corresponding alpha'-acetoxy-alpha'-phenyl substituted oxidation products in good yields. The tandem oxidation to monoacetoxylation ratio can be tuned by the amount of manganese(III) acetate.
Manganese(III) acetate promoted acetoxylation of various α,β-unsaturated cyclopentanones
Tanyeli, Cihangir; Turkut, Engin; SEZEN, Bengü (Elsevier BV, 2003-02-10)
We describe the results of manganese(III) acetate based regioselective oxidation of various alpha,beta-unsaturated cyclopentanones leading to alpha'-acetoxy alpha,beta-unsaturated cyclopentanones in good yields. Products due to monophenyl and diphenyl substituted dimerization have been identified as byproducts of the reaction.
Manganese(III) acetate-mediated oxidative coupling of phenylhydrazines with furan and thiophene: a novel method for hetero biaryl coupling
Demir, Ayhan Sıtkı; Reis, O; Emrullahoglu, M (Elsevier BV, 2002-09-30)
A convenient new method for the arylation of furan and thiophene with arylhydrazine and manganese(III) acetate is described. Oxidation of arylhydrazines with Mn(III) acetate in furan or thiophene affords the corresponding 2-aryl-substituted furans and thiophenes in good yield using commercially available materials; access to 2-substituted heterobiaryls works selectively, and coupling occurs with loss of the hydrazine moiety.
Citation Formats
M. F. Ali, R. A. Caliskan, E. ŞAHİN, and M. Balcı, “Manganese(III)-mediated oxidative free-radical additions of 1,3-dicarbonyl compounds to homobenzonorbornadiene and benzobarrelene: mechanistic studies,” TETRAHEDRON, pp. 1430–1437, 2009, Accessed: 00, 2020. [Online]. Available: