A general method for the alkaline cleavage of enolisable ketones

Žabjek, Alenka; Petrič, Andrej

doi:10.1016/s0040-4039(99)01262-9

Cited by 33 publications

(12 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, the radiochemical yield of [ 18 F]FENE did not exceed 11%, even with prolonged heating and with little [ 18 F]FDDNP remaining in the basic reaction mixture (Table 2, entry 10). In addition to the possible reaction of naphthyl ketones in basic solution [32], the ethylidenemalononitrile moiety in [ 18 F]FDDNP, due to the extreme polarity of the double bond, may suffer dimerization [33,34]. Therefore, removing the base from the reaction mixture by using acid prevented these secondary reactions from happening during isolation and purification, thereby increasing the reproducibility of the synthesis.…”

Section: Resultsmentioning

confidence: 99%

High-Yield, Automated Radiosynthesis of 2-(1-{6-[(2-[18F]Fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([18F]FDDNP) Ready for Animal or Human Administration

et al. 2006

Self Cite

View full text Add to dashboard Cite

The biomarker 2-(1-{6-[(2-[(18)F]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([(18)F]FDDNP) is used as a positron emission tomography (PET) imaging probe for Alzheimer's disease and other neurodegenerative diseases. A high-yield and fully automated synthesis of [(18)F]FDDNP--along with the synthesis and characterization of non-radioactive FDDNP, a fluorescent probe derived from 2-(1,1-dicyanopropenyl-2)-6-dimethylaminonaphthalene (DDNP)--are reported. Radiofluorination of the tosyloxy precursor 2-{[6-(2,2-dicyano-1-methylvinyl)-2-naphthyl](methyl)amino}ethyl-4-methylbenzenesulfonate (DDNPTs) with K(18)F/Kryptofix 2.2.2. yielded chemically (>99%) and radiochemically (>99%) pure [(18)F]FDDNP in high radiochemical yields (40-60%; n> 120), with specific activities ranging from 4 to 8 Ci/mumol at the end of synthesis (90 minutes). Both remote, semiautomated and automated synthesis procedures are described. Either approach provides a reliable method for production of large quantities (110-170 mCi from 500 mCi of [(18)F]fluoride) of [(18)F]FDDNP allowing for multiple PET experiments in the same day or for distribution of the tracer from a single cyclotron facility to PET imaging centers at various geographical distances.

show abstract

Section: Resultsmentioning

confidence: 99%

High-Yield, Automated Radiosynthesis of 2-(1-{6-[(2-[18F]Fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([18F]FDDNP) Ready for Animal or Human Administration

et al. 2006

Self Cite

View full text Add to dashboard Cite

show abstract

“…64 Under alkaline conditions, oxidative cleavage of vicinal diols into the dicarboxylic acid is catalyzed by Ru‐based pyrochlore oxides, A 2+ x Ru 2− x O 7− y (A=Pb, Bi; 0< x <1; 0< y <0.5), at room temperature 65. 66 In fact, direct oxidation of alcohols into acids brought about with Group VIII elements is usually performed under basic conditions 67–75…”

Section: Introductionmentioning

confidence: 99%

Oxidation of 1,2‐Cyclohexanediol to Adipic Acid with Oxygen: A Study Into Selectivity‐Affecting Parameters

Rozhko¹,

Raabová²,

Macchia³

et al. 2013

ChemCatChem

View full text Add to dashboard Cite

The aerobic oxidation of trans‐1,2‐cyclohexanediol in the synthesis of adipic acid was studied. Two classes of catalysts are compared, 1) alumina‐supported Ru(OH)3, and 2) Keggin type P/Mo/V polyoxometalates. These two classes are representative examples because they are active in alcohol oxidation under quite different reaction conditions. In the former case, basic conditions are needed in order to activate the substrate, whereas with polyoxometalates, acidic conditions are used. Their catalytic behavior showed remarkable differences; in basic conditions, the reaction network was very complex, and several side reactions led to a number of by‐products, with a low selectivity to adipic acid in the end. The supported Ru(OH)3 catalyst was very efficient in 1,2‐cyclohexanediol oxidative dehydrogenation to 1,2‐cyclohexanedione, but several undesired reactions occurred starting from this key intermediate under basic conditions: rearrangement into 6‐hydroxycaprolactone and 1‐hydroxycyclopentanecarboxylic acid, and formation of the product of aldol condensation. The former compound was also an intermediate for adipic acid formation, but this reaction gave only a minor contribution to the reactant conversion. Polyoxometalates were extremely selective in 1,2‐cyclohexanediol conversion into adipic acid, but under acidic conditions the product reacted with the unconverted reactant to yield the corresponding ester.

show abstract

“…We found that for 1 mmol of acetophenone derivative 1.2 mmol of CAN was enough to carry out the reaction to completion, in contrast to the other oxidation reactions, which required more than two equivalents of the reagents [3,[5][6][7][8]. Recently, this oxidation reaction has been carried out by two reagents in two steps using two equivalents of one reagent [9].…”

Section: Resultsmentioning

confidence: 99%

“…The oxidative cleavage reaction of enolizable ketones was also reported utilizing reagents such as potassium hydroxide [8] and [hydroxy-(2,4-dinitro-benzenesulfonyloxy)iodo] benzene/tetrabutyl ammonium periodate [9]. Ceric(IV) ammonium nitrate (CAN) is known to be an important reagent in oxidation reactions [10], as well as carbon-carbon [11] and carbon-nitrogen [12] bond-forming reactions.…”

Section: Introductionmentioning

confidence: 99%

Direct synthesis of p-nitrobenzoic acid and benzoic acids from benzyl ketones and acetophenones using the CAN/HOAc system

Khodaei

Khosropour

Moghanian

2007

JICS

View full text Add to dashboard Cite

A general method for the alkaline cleavage of enolisable ketones

Cited by 33 publications

References 11 publications

High-Yield, Automated Radiosynthesis of 2-(1-{6-[(2-[18F]Fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([18F]FDDNP) Ready for Animal or Human Administration

High-Yield, Automated Radiosynthesis of 2-(1-{6-[(2-[18F]Fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile ([18F]FDDNP) Ready for Animal or Human Administration

Oxidation of 1,2‐Cyclohexanediol to Adipic Acid with Oxygen: A Study Into Selectivity‐Affecting Parameters

Direct synthesis of p-nitrobenzoic acid and benzoic acids from benzyl ketones and acetophenones using the CAN/HOAc system

Contact Info

Product

Resources

About