2005-10-9Relevant academic research and scientific papers
A metal-free oxidation of benzo[c]chromen to benzo[c]chromen-6-ones by t-butyl hydroperoxide in the presence of potassium iodide
Zhou, Jing,Han, Pan,Xu, Ying-Meng,Zhang, Tao,Du, Zhen-Ting
, p. 1889 - 1896 (2013)
An effective and eco-friendly oxidation method for the synthesis of benzo[c]chromen-6-ones is described. The condition constitutes 6 molar ratio TBHP, catalytic KI and pyridine in acetonitrile as the solvent. Altogether, 16 structurally diverse substituted benzo[c]chromen-6-ones were prepared through this protocol from corresponding benzo[c]chromenes in excellent yields. The Japan Institute of Heterocyclic Chemistry.
NMR-Spectroskopische Untersuchung von Isocumarin- und Isocarbostyril-Derivaten
Duddeck, Helmut,Kaiser, Manfred
, p. 913 - 924 (1985)
The syntheses and the 1H, 13C and 15N NMR spectra of 47 isocumarin and isocarbostyril derivatives are reported and discussed.The data include T1 relaxation times and geometries of some complexes with Yb(dpm)3.
Efficient one-pot synthesis of dibenzopyranones via a decarboxylative cross-coupling and lactonization sequence
Luo, Jiaying,Lu, Youling,Liu, Saiwen,Liu, Jing,Deng, Guo-Jun
, p. 2604 - 2608 (2011)
A highly selective palladium bis(acetoacetonate)/copper(I) chloride [Pd(acac)2/CuCl] catalytic system for the preparation of dibenzopyranones has been developed. Tandem decarboxylative coupling and lactonization can be realized in one pot using commercially available starting materials. The reaction proceeded well for a range of different substrates. Copyright
Reactivity in the formation of lactones from aromatic carboxylic acids with organohypervalent iodine compounds in the Suarez system
Muraki, Takahito,Togo, Hideo,Yokoyama, Masataka
, p. 1713 - 1716 (1999)
The reactivity of various iodanes, such as (diacetoxyiodo)arenes, the Dess-Martin reagent, and (arylsulfonyloxy)benziodoxolones, with (o-alkyl)- and (o-phenyl)arenecarboxylic acids in the presence of iodine (Suarez system) was studied to give the corresponding lactones via oxygen-centered radicals. (Diacetoxyiodo)arenes gave the lactones in good yields, while 1-(arylsulfonyloxy)benziodoxolones gave lactones together with the iodinated lactones. The Dess-Martin reagent also showed the same reactivity as (diacetoxyiodo)arenes to give the lactones. Among them, (diacetoxyiodo)toluene showed the best reactivity for the conversion of these carboxylic acids to the corresponding lactones.
Palladium-catalyzed one-pot Suzuki-Miyaura cross coupling followed by oxidative lactonization: A novel and efficient route for the one-pot synthesis of benzo[c]chromene-6-ones
Singha, Raju,Roy, Soumyabrata,Nandi, Sukla,Ray, Priyanka,Ray, Jayanta K.
, p. 657 - 660 (2013)
A number of 6H-benzo[c]chromene-6-ones, 5H-naphtho[1,2-c]chrome-5-ones, and 6H-naphtho[2,1-c]chromene-6-one have been synthesized starting with 2-hydroxyphenylboronic acid and o-bromobenzaldehyde or o-bromonaphthalene carboxaldehyde derivatives via a one-pot Suzuki-Miyaura cross coupling followed by oxidative lactonization reactions. The overall transformation consists of three reactions: Suzuki-Miyaura cross coupling, hemi-acetal formation, and oxidation.
The synthesis of substituted benzo[c]chromen-6-ones by a Suzuki coupling and lactonization sequence using ionic liquids - From laboratory scale to multi-kilogram synthesis
Kemperman, Gerardus J.,Ter Horst,Van De Goor,Roeters,Bergwerff,Van Der Eem,Basten
, p. 3169 - 3174 (2006)
A series of benzo[c]chromen-6-ones are prepared by a Suzuki coupling and lactonization sequence starting with 2-methoxyphenylboronic acids and methyl 2-bromobenzoate derivatives. The use of ionic liquids in this synthesis has been explored. It was found that the Suzuki coupling proceeds much faster when a catalytic amount of the ionic liquid [BMIM][PF6] is used. By using the Lewis acidic ionic liquids [BMIM][Al2Cl7] or [TMAH][Al2Cl7] the methyl 2-(2-methoxyphenyl)benzoate product obtained from the Suzuki coupling can be converted to benzo[c]chromen-6-ones in one step, while the conventional route involves three steps. The use of ionic liquids is demonstrated in the synthesis of a variety of benzo[c]chromen-6-ones. It is also shown that the application of ionic liquids is not limited to laboratory scale experiments, as a process was developed and performed on a multi-kilogram scale. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
Intramolecular Aromatic C-H Acyloxylation Enabled by Iron Photocatalysis
Xia, Siqi,Hu, Kunjun,Lei, Chuanhu,Jin, Jian
, p. 1385 - 1389 (2020)
A mild and efficient protocol for the intramolecular aromatic C-H oxygenation of 2-biphenylcarboxylic acids has been achieved via iron photocatalysis. The 2-biphenylcarboxylic acids with a diverse array of substituents at both phenyl rings could furnish the oxygenation products in good to excellent yields. We speculate that the aryl carboxylate-iron(III) complexes should generate the aroyloxy radicals and iron(II) upon visible light irradiation.
Donor-acceptor biaryl lactones: PH induced molecular switches with intramolecular charge transfer modulation
Carlson, Erik J.,Riel, Asia Marie S.,Dahl, Bart J.
, p. 6245 - 6249,5 (2012)
The physical properties of biaryl-containing compounds are known to be highly dependent on molecular geometry. We report the syntheses and fundamental spectroscopic study of two donor-acceptor biaryl lactone (6H-benzo[c]chromen-6- one) pH-driven switches.
Synthesis of unstable cyclic peroxides for chemiluminescence studies
Bartoloni, Fernando H.,De Oliveira, Marcelo A.,Augusto, Felipe A.,Ciscato, Luiz Francisco M. L.,Bastos, Erick L.,Baader, Wilhelm J.
, p. 2093 - 2103 (2012)
Cyclic four-membered ring peroxides are important high-energy intermediates in a variety of chemi and bioluminescence transformations. Specifically, a-peroxylactones (1,2-dioxetanones) have been considered as model systems for efficient firefly bioluminescence. However, the preparation of such highly unstable compounds is extremely difficult and, therefore, only few research groups have been able to study the properties of these substances. In this study, the synthesis, purification and characterization of three 1,2-dioxetanones are reported and a detailed procedure for the known synthesis of diphenoyl peroxide, another important model compound for the chemical generation of electronically excited states, is provided. For most of these peroxides, the complete spectroscopic characterization is reported here for the first time.
Remote Functionalization (1) : Synthesis of γ- and δ-Lactones from Aromatic Carboxylic Acids
Togo, Hideo,Muraki, Takahito,Yokoyama, Masataka
, p. 7089 - 7092 (1995)
Oxidative cyclization of o-alkyl- or o-arylaromatic carboxylic acids with benzene and iodine via aromatic carbonyloxy radicals gave the corresponding lactones in good yields.
