2,3-dioxabicyclo[2.2.2]oct-7-en-5-one: Synthesis and reactions of the keto endoperoxide of phenol

Adam, W
Balcı, Metin
Kilic, H
The photooxygenation of 1,4-cyclohexadiene (3) affords the diastereomeric hydroperoxy endoperoxides exo-4 and endo-4 and the diastereomeric hydroperoxides trans-5 and cis-5 in a ratio of 87: 9:3.5:0.5. Selective reduction of hydroperoxide group in the endoperoxides exo-4 and endo-4 in the presence of titanium tetraisopropoxide-diethyl sulfide gave the corresponding hydroxy endoperoxides exo-7 and endo-7, which on PCC oxidation leads to the phenol-derived keto endoperoxide 2. The triphenylphosphine deoxygenation of the keto endoperoxide 2 produces a 9:1 mixture of 1,2- and 1,4-dihydroxybenzenes 10 and 11, while the CoTPP-catalyzed rearrangement affords the bisepoxide 12, malealdehyde (13), and beta-lactone 14. The mechanisms of these transformations are presented.


A new method for the synthesis of stipitatic acid isomers: Photooxygenation of ethyl 6H-cyclohepta[d][1,3]dioxole-6-carboxylate
Dastan, A; Saracoglu, N; Balcı, Metin (2001-09-01)
Photooxygenation of the cycloheptatriene derivative 9 gave the bicyclic endoperoxide 14. Cleavage of the peroxide linkage in 14 with thiourea resulted in the formation of 16. Treatment of the endoperoxide 14 with a catalytic amount of triethylamine provided a new isomer of stipitatic acid 11, and 16. Pyrolysis or the CoTPP (TPP = tetraphenylporphyrin) catalyzed reaction of 14 resulted in the formation of iso-stipitatic acid 10, and 18,
A novel and short synthesis of (1,4/2)-cyclohex-5-ene-triol and its conversion to (+/-)-proto-quercitol
Gultekin, MS; Salamci, E; Balcı, Metin (2003-07-29)
(1,4/2)-Cyclohex-5-ene-triol was synthesized starting from cyclohexa-1,4-diene with two different approaches. Photooxygenation of cyclohexa-1,4-diene and epoxy-cyclohexene afforded anti-2,3-dioxabicyclo[2.2.2]oct-7-en-5-yl hydroperoxide and anti-7-oxabicclo[4.1.0]hept-4-en-3-yl hydroperoxide, respectively. Hydroperoxy endoperoxide was reduced with aqueous sodium bisulfite; hydroperoxy-epoxide with dimethylsulfide-titanium tetraisopropoxide to give 7-oxabicyclo[4.1.0]hept-4-en-3-ol. Acidic hydrolysis of the ...
Addition of dibromocarbene to cyclobutene: characterisation and mechanism of formation of the products
Algi, Fatih; Hokelek, Tuncer; Balcı, Metin (2004-10-01)
Cyclobutene reacted with dibromocarbene in solution to give 1,5-dibromocyclopent-1-ene (9), 1,2,6, 6-tetrabromobicyclo[3.1.0]hexane (10), and 1,2,3,6-tetrabromocyclohex-1-ene (11), in a ratio of 1:4:8, respectively. Compounds 10 and 11 were found to be formed from a second carbene addition and rearrangement under the given reaction conditions.
2,1,3-Benzooxadiazole, thiophene and benzodithiophene based random copolymers for organic photovoltaics: Thiophene versus thieno[3,2-b]thiophene as pi-conjugated linkers
Göker, Seza; Hizalan, Gonul; Aktas, Ece; Kutkan, Seda; Çırpan, Ali; Toppare, Levent Kamil (2017-04-02)
Three conjugated random copolymers comprising benzodithiophene and thiophene as the donor units and benzooxadiazole as the acceptor unit, spaced with thiophene and thieno[3,2-b]thiophene π-bridges, were designed and synthesized. The effects of different linkers on the optical and electrochemical properties were investigated. The polymer containing a thieno[3,2-b]thiophene π-bridge revealed a red shifted absorption compared to its thiophene analogue. Morphological and photovoltaic properties of a polymer:ful...
KOTZIAN, M; KREITER, CG; MICHAEL, G; Özkar, Saim (Wiley, 1983-01-01)
Irradiation of Cr(CO)5[P(CH3)3] or Cr(CO)5[P(OCH3)3] in presence of 1,3‐butadiene (1), trans‐1,3‐pentadiene (2), and 2‐ethyl‐1,3‐butadiene (3), trans, trans‐2,4‐hexadiene (4), 2‐methyl‐1,3‐pentadiene (5), and 2‐ethyl‐1,3‐butadiene (6) produces in good yields Cr(CO)3L(η4‐diene) complexes (LP(CH3)3 1A–6A; LP(OCH3)3 1B–6B). The configurations of these complexes were determined by IR and NMR spectroscopy (1H, 13C, 31P). Cr(CO)3[P(OCH3)3](η4‐1,3‐pentadiene) (2B) and Cr(CO)3[P(OCH3)3](η4‐2,4‐hexadiene) (4B) for...
Citation Formats
W. Adam, M. Balcı, and H. Kilic, “2,3-dioxabicyclo[2.2.2]oct-7-en-5-one: Synthesis and reactions of the keto endoperoxide of phenol,” JOURNAL OF ORGANIC CHEMISTRY, pp. 5926–5931, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57841.