122673-91-0Relevant academic research and scientific papers
Palladium-Catalyzed Intermolecular Heck-Type Reaction of Epoxides
Teng, Shenghan,Tessensohn, Malcolm E.,Webster, Richard D.,Zhou, Jianrong Steve
, p. 7439 - 7444 (2018/07/15)
The palladium-catalyzed intermolecular Heck-type reaction of both cyclic and acyclic epoxides is reported with tolerance of typical polar groups and acidic protons. Suitable alkenes include styrenes, conjugate dienes, and some electron-deficient olefins. In reactions of aliphatic terminal epoxides, ring opening occurs selectively at terminal positions, and stereocenters of epoxides are fully retained. Mechanistic studies provide evidence for in situ conversion of epoxides to β-halohydrins, generation of alkyl radicals, and radical addition to alkenes as key steps. Cyclovoltammetric determination of reduction potentials suggests that during activation of alkyl iodides by palladium(0) complexes, inner-sphere halogen abstraction is more likely than outer-sphere single electron transfer.
Regio- and stereoselective co-iodination of olefins using NH4I and Oxone
Durgaiah, Chevella,Naresh, Mameda,Arun Kumar, Macharla,Swamy, Peraka,Reddy, Marri Mahender,Srujana, Kodumuri,Narender, Nama
supporting information, p. 1133 - 1144 (2016/07/22)
A simple, efficient, and environmentally benign protocol for the synthesis of vicinal iodohydrins and iodoesters from olefins using NH4I and Oxone in CH3CN/H2O (1:1) and dimethylformamide (DMF) / dimethylacetamide (DMA), respectively, without employing a catalyst at room temperature is described. Regio- and stereoselective iodohydroxylation and iodoesterification of various olefins with anti fashion, following Markonikov’s rule, was achieved and the corresponding products were obtained in good to excellent yields. In addition, 1,2-disubstituted olefins afforded excellent diastereoselectivity.
Regioselective vicinal functionalization of unactivated alkenes with sulfonium iodate(i) reagents under metal-free conditions
Rao, Dodla S.,Reddy, Thurpu R.,Babachary, Kalvacherla,Kashyap, Sudhir
, p. 7529 - 7543 (2016/08/16)
Metal-free, molecular iodine-free direct 1,2-difunctionalization of unactivated alkenes has been reported. The sulfonium iodate(i) reagent efficiently promoted the intermolecular vicinal iodo-functionalization of a diverse range of olefins in a stereo and regioselective manner. This method enables the divergent and straightforward preparation of synthetically useful functionalities; β-iodocarboxylates, β-iodohydrins, and β-iodoethers in a one-step process. Further interconversion of iodo-functionalized derivatives allows easy access to valuable synthetic intermediates en route to biologically active molecules.
1,3,2,4-diazadiphosphetidine-based phosphazane oligomers as source of P(III) atom economy reagents: Conversion of epoxides to vic -haloalcohols, vic -dihalides, and alkenes in the presence of halogen sources
Iranpoor, Nasser,Firouzabadi, Habib,Etemadidavan, Elham
, p. 1165 - 1173 (2014/10/16)
1,3,2,4-Diazadiphosphetidines (P1-P3), as easily prepared, stable, and heterogeneous P(III) compounds, were used for the efficient conversion of epoxides to vic-halohydrins, vic-dihalides, or alkenes in the presence of different halogen sources in CH3CN. Of these phosphazanes, P3 is most suitable and contains 4 phosphorous atoms with the advantage of having greater atom economy and its phosphorus oxide byproduct can be easily separated from the reaction mixture by simple filtration. The nitrogen atoms in this molecule can also act as acid scavengers in the reaction.
Enzymatic preparation of (1S,2R)- and (1R,2S)-stereoisomers of 2-halocycloalkanols
Kolodiazhna, Olga O.,Kolodiazhna, Anastasy O.,Kolodiazhnyi, Oleg I.
, p. 37 - 42 (2013/02/25)
The stereoisomers of cis-2-halocycloalkanols were resolved by a kinetically controlled transesterification with vinyl acetate in the presence of lipases in organic media. High enantioselectivities (ee >98%) and good isolated yields were obtained for all substrates using the appropriate lipase. Burkholderia cepacia lipase was the most efficient enzyme for the resolution of these substrates. The enantiomeric purities of the compounds were defined by derivatization with Mosher's acid and the absolute configurations were determined by chemical correlation.
Dichloroiodoisocyanuric acid: A new reagent for regioselective coiodination of alkenes and iodination of activated arenes
Da Silva Ribeiro, Rodrigo,Esteves, Pierre M.,De Mattos, Marcio C.S.
experimental part, p. 228 - 235 (2012/05/05)
Dichloroiodoisocyanuric acid was prepared in 93% by heating trichloroisocyanuric acid with 1.05 mol equiv. of iodine. This new reagent is very efficient for regioselective electrophilic iodination of activated arenes. Alkenes react with dichloroiodoisocyanuric acid in the presence of oxygenated nucleophiles (water, alcohols, and acetic acid), leading to the corresponding iodohydrins, β-iodoethers and β-iodoacetates with reaction times of less than one minute and with a high degree of regioselectivity. Enol ethers resulted in the regioselective formation of the corresponding iodine-dialkylacetals. Experimental results and DFT calculations showed that dichoroiodoisocyanuric acid is more reactive with unsaturated systems than triiodoisocyanuric acid.
H2TPP organocatalysis in mild and highly regioselective ring opening of epoxides to halo alcohols by means of halogen elements
Torabi, Parviz,Azizian, Javad,Zomorodbakhsh, Shahab
experimental part, p. 5508 - 5519 (2012/08/28)
We found that elemental iodine and bromine are converted to trihalide nucleophiles (triiodine and tribromide anion, respectively) in the presence of catalytic amounts of meso-tetraphenylporphyrins (H2TPP). Therefore a highly regioselective method for the synthesis of β-haloalcohols through direct ring opening of epoxides with elemental iodine and bromine in the presence of H2TPPs as new catalysts is described. At room temperature a series of epoxide derivatives were converted into the corresponding halohydrins resulting from an attack of trihalide species anion atoms at the less substituted carbon atom. This method occurs under neutral and mild conditions with high yields in various aprotic solvents, even when sensitive functional groups are present.
Enzymatic resolution of stereoisomers of 2-iodocyclohexanol
Kolodiazhna,Kolodiazhna,Kolodiazhnyi
, p. 2175 - 2177 (2013/10/01)
All four optically active stereoisomers of 2-iodocyclohexanol were synthesized. Their enantiomeric purity was determined upon derivatization with Mosher's acid, absolute configuration have been established by chemical correlation.
Radical amination with trimethylstannylated benzophenone imine
Lamas, Marie-Celine,Vaillard, Santiago E.,Wibbeling, Birgit,Studer, Armido
supporting information; experimental part, p. 2072 - 2075 (2010/07/07)
Figure presented Intermolecular radical amination reactions of various primary, secondary, and tertiary alkyl radicals by using trimethylstannylated benzophenone imine A as a novel radical acceptor to provide imines of type B are described. These imines are readily reduced with NaBH4 to the corresponding secondary amines C. The novel radical amination can be combined with typical radical cyclization reactions.
m-Iodosylbenzoic acid, a tagged hypervalent iodine reagent for the iodo-functionalization of alkenes and alkynes
Yusubov, Mekhman S.,Yusubova, Roza Ya.,Kirschning, Andreas,Park, Joo Yeon,Chi, Ki-Whan
, p. 1506 - 1509 (2008/09/19)
An efficient and facile method for the iodo-functionalization of alkenes 5 and alkynes 6 by using recyclable m-iodosylbenzoic acid (2) was developed. The final products can be easily isolated without any chromatographic purification by simple treatment of the crude mixture with an anionic exchange resin. Unreacted m-iodosylbenzoic acid and reduced m-iodobenzoic acid are effectively recovered from the resin by acidification with hydrochloric acid.
