Studies towards the synthesis of polyoxygenated steroids. Reaction of some tri- and tetra-substituted monoene steroids with RuO4

Piccialli, Vincenzo; Smaldone, D.; Sica, Donato

doi:10.1016/s0040-4020(01)85739-2

Cited by 43 publications

(26 citation statements)

References 26 publications

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“…Among many oxidation systems proposed for the upgrading of heavy oils, ruthenium‐ion‐catalyzed oxidation (RICO) is potentially an attractive approach, as selectivity in this reaction can be easily controlled by the reaction time, substrate:oxidant ratio, pH of the solution and type of solvent used . Consequently, RICO is exceptionally versatile, and it has been reported to be effective for many reactions, including the dihydroxylation of olefins, selective mono‐oxidation of vicinal diols, keto‐α‐hydroxylation, oxidative cyclization of polyenes, oxidative cleavage of double and triple bonds, oxidation of heteroatoms and oxidation of saturated hydrocarbons and aromatic hydrocarbons . The cost of RICO chemistry is relatively high, due to the use of ruthenium and the oxidant.…”

Section: Introductionmentioning

confidence: 99%

Oxidation of Polynuclear Aromatic Hydrocarbons using Ruthenium‐Ion‐Catalyzed Oxidation: The Role of Aromatic Ring Number in Reaction Kinetics and Product Distribution

Nowicka

Clarke

Sankar

et al. 2017

Chemistry A European J

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Oxidation of aromatic hydrocarbons with differing numbers of fused aromatic rings (2-5), have been studied in two solvent environments (monophasic and biphasic) using ruthenium-ion-catalyzed oxidation (RICO). RICO reduces the aromaticity of the polyaromatic core of the molecule in a controlled manner by selective oxidative ring opening. Moreover, the nature of the solvent system determines the product type and distribution, for molecules with more than two aromatic rings. Competitive oxidation between substrates with different numbers of aromatic rings has been studied in detail. It was found that the rate of polyaromatic hydrocarbon oxidation increases with the number of fused aromatic rings. A similar trend was also identified for alkylated aromatic hydrocarbons. The proof-of-concept investigation provides new insight into selective oxidation chemistry for upgrading of polyaromatic molecules.

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Section: Introductionmentioning

confidence: 99%

Oxidation of Polynuclear Aromatic Hydrocarbons using Ruthenium‐Ion‐Catalyzed Oxidation: The Role of Aromatic Ring Number in Reaction Kinetics and Product Distribution

Nowicka

Clarke

Sankar

et al. 2017

Chemistry A European J

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“…1,2 Though the most popular process mediated by PCC is the oxidation of primary and secondary alcohols to aldehyde and ketones, respectively, many other functional groups undergo PCC oxidation. As a continuation of our interest in oxidative processes mediated by transition metal oxo-species [3][4][5][6][7][8][9][10][11] as well as in the synthesis and derivatization of new THF-containing compounds, [12][13][14][15][16][17][18][19][20][21] we recently focused on oxidation processes mediated by PCC. These studies led to the discovery of new interesting transformations including oxidative spiroketalization, 22 oxidative cleavage of trisubstituted mono-THF compounds 23 and synthesis of bis--acyloxy-1,4-and 1,5-diketones from THF and THP-diols, respectively.…”

Section: Introductionmentioning

confidence: 99%

Pyridinium chlorochromate chemistry. New insight into oxidation of tetrahydrofurans

Zaccaria¹,

Borbone²,

Oliviero³

et al. 2017

Arkivoc

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A thorough investigation of the minor oxidation products of two penta-tetrahydrofuran compounds with pyridinium chlorochromate has been carried out. Isolation of ring-B oxygenated spiroketal and degradation products, including polycyclic mono-and bis-lactone compounds, supports the previously postulated involvement of cyclic enolether intermediates in the oxidation of THF and poly-THF substances with PCC. Based on the collected evidence, a new mechanistic route for the PCC-mediated oxidative cleavage of -hydroxy-THF compounds to -lactones has been postulated. The proposed mechanism well agrees with the one reported for the oxidative cleavage of 8-hydroxy-neoisocedranol oxide by RuO4, a fact that further supports our previous observation on the similar oxidizing behaviour shown by PPC and RuO4 towards THFcontaining compounds.

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“…The oxidative cleavage of unsaturated fatty acids into either aldehydes or carboxylic acids is a reaction of considerable practical interest. [1][2][3] This conversion is nowadays mostly performed with second-and third-row transition-metal catalysts based on Os, [4][5][6][7][8][9][10][11][12] Ru, [13][14][15][16][17][18] or W, [19][20][21][22][23][24][25] on the lab scale, or with ozone in an industrial process. [3,26] More benign methods for these processes are clearly desired.…”

Section: Introductionmentioning

confidence: 99%

Fe‐Catalyzed One‐Pot Oxidative Cleavage of Unsaturated Fatty Acids into Aldehydes with Hydrogen Peroxide and Sodium Periodate

Spannring

Yazerski

Bruijnincx

et al. 2013

Chemistry A European J

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A one-pot method has been developed for the oxidative cleavage of internal alkenes into aldehydes by using 0.5 mol% of the nonheme iron complex [Fe(OTf)2(mix-bpbp)] (bpbp=N,N'-bis(2-picolyl)-2,2'-bipyrrolidine) as catalyst and 1.5 equivalents of hydrogen peroxide and 1 equivalent of sodium periodate as oxidants. A mixture of diastereomers of the chiral bpbp ligand can be used, thereby omitting the need for resolution of its optically active components. The cleavage reaction can be performed in one pot within 20 h and under ambient conditions. Addition of water after the epoxidation, acidification and subsequent pH neutralization are crucial to perform the epoxidation, hydrolysis, and subsequent diol cleavage in one pot. High aldehyde yields can be obtained for the cleavage of internal aliphatic double bonds with cis and trans configuration (86-98%) and unsaturated fatty acids and esters (69-96%). Good aldehyde yields are obtained in reactions of trisubstituted and terminal alkenes (62-63%). The products can be easily isolated by a simple extraction step with an organic solvent. The presented protocol involves a lower catalyst loading than conventional methods based on Ru or Os. Also, hydrogen peroxide can be used as the oxidant in this case, which is often disproportionated by second- and third-row metals. By using only mild oxidants, overoxidation of the aldehyde to the carboxylic acid is prevented.

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Studies towards the synthesis of polyoxygenated steroids. Reaction of some tri- and tetra-substituted monoene steroids with RuO4

Cited by 43 publications

References 26 publications

Oxidation of Polynuclear Aromatic Hydrocarbons using Ruthenium‐Ion‐Catalyzed Oxidation: The Role of Aromatic Ring Number in Reaction Kinetics and Product Distribution

Oxidation of Polynuclear Aromatic Hydrocarbons using Ruthenium‐Ion‐Catalyzed Oxidation: The Role of Aromatic Ring Number in Reaction Kinetics and Product Distribution

Pyridinium chlorochromate chemistry. New insight into oxidation of tetrahydrofurans

Fe‐Catalyzed One‐Pot Oxidative Cleavage of Unsaturated Fatty Acids into Aldehydes with Hydrogen Peroxide and Sodium Periodate

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