Deuterated acetone

Isotope labeling by derivative formation with deuterated reagents is useful for the preparation of analogs such as dg-acetonides, da-acetates, da-methyl ethers, dg-methyl esters, etc. The required reagents are either commercially available or can be easily prepared. (The preparation of da-methyl iodide is described in section IX-F. Various procedures are reported in the literature for the preparation of dg-acetone, da-diazometh-ane57.i63.i73 and da-acetyl chloride. ) These reactions can be carried out under the usual conditions and they need no further discussion. A convenient procedure has been reported for the da-methylation of sterically hindered or hydrogen bonded phenolic hydroxyl functions by using da-methyl iodide and sodium hydroxide in dimethyl sulfoxide solution. This procedure should be equally applicable to the preparation of estradiol da-methyl ether derivatives. 

Write the complete mechanism of the deuteration of acetone on treatment with D30+. 

The isotopic method has been used in conjunction with a flow apparatus by Stranks, to measure the exchange between the cyclopentadienyl complexes of iron (III) and iron (II) in methanol. Separation was based on the insolubility of Fe(C5H5) in petroleum ether at —80 °C. Using Fe(II) and Fe(III) 10 M and short reaction times ( msec), a rate coefficient 8.7 x 10 l.mole .sec at — 75 °C was obtained. The rate of exchange in the presence of chloride ions and inert electrolytes was found to be more rapid. Calculations using Marcus Theory showed reasonable agreement with the experimental observations. In deuterated acetone, line broadening measurements have led to an estimate of this rate coefficient of > 10 l.mole . sec at 26 °C. 

Somewhat later it was hypothesized that mechanochemical and sonochemical phenomena indnced by gas-bnbble transformations could be of decisive importance. Several serions scientihc gronps have np to now looked at this problem. The mechanism being tested by them is not able, of course, to satisfy the power levels claimed in nuclear reactions, bnt it is of high scientihc interest. It has already been found that it is not at all compnlsory to generate the gas electrolytically in order to utilize the energy of the bubbles, and that the gas itself need not at all contain deuterium. One of the model reactants nsed in cnrrent investigations in this area, more particularly, is deuterated acetone CjDgO. 

Plant material is homogenized in acetone followed by addition of water. The filtered extract is diluted with acetone-water (2 1 v/v) and filtered through a syringe filter. The sample extract is diluted 1 1 with a deuterated azinphos-methyl internal standard and analyzed using LC/MS/MS in the positive-ion selected reaction monitoring (-I-SRM) mode. 

Combine a 0.5-mL aliquot of the Anal sample exAact or a 0.020 igmL azinphos-methyl standard solution in acetone-water (2 1 v/v) with 0.5 mL of a 0.040 ig mL deuterated internal standard solution in methanol-water (2 3 v/v) in an HPLC autosampler vial. Combination may be made using other volumes as long as the solutions are combined 1 1 (v/v). Inject 200 aL from the 0.020 and 0.040 igmL standard/internal standard soluAon. Inject 200 aL from each of the 10 sample exAact/ internal standard soluAons. Inject 200 p-L from anoAier 0.020 and 0.040 pgmL standard/internal standard solution. 

The condensation reaction in deuterium revealed that up to 92% of the acetone undergoes deuterium exchange to form various states of deuterated acetone, with C3H5DO present as the most populated species at ca. 60%. These results indicate that the exchange process is extremely facile even on a catalyst only containing weakly basic sites. Various deuterated products were observed in all of the reaction products, implying that there is significant H-transfer... 

Figure 5 Proposed mechanism for acetone condensation reaction under deuterated conditions.

Further studies by Spenser demonstrated that l,2-13C-labeled acetate (13) was incorporated into lycopodine but gave a distribution of the labels that did not account for the pelletierine-route that was hypothesized (Scheme 6.2) [11]. An intact 3-carbon unit was desired for testing, but labeled acetoacetate (l,2,3,4-13C-acetoacetate (14), which could undergo decarboxylation to provide an intact 3-carbon unit) was found to give the same incorporation pattern as acetate (and therefore must have been cleaved to acetate prior to uptake). In addition, feeding studies using deuterated, 13C-labeled acetate provided a loss or washout of deuterium at the C16 methyl group. This could only occur if an intermediate had formed that would provide for facile enolization. Both the equal distribution of the 13C labels and loss of the deuteriums led the researchers to propose that the intermediate was symmetric, such as acetone dicarboxylic acid (15). 

In the spring of 2002, the research group of Oak Ridge National Laboratory [ORNL] has reported [1] that if USW is irradiated on deuterated acetone (C3D60), nuclear emission is observed and the thermonuclear reactions ... 

Illinois group [2] has expressed a negative version on ORNL group, but their estimation of rc was done for water, so that it was too small to give enough potential to the initial bubble. Their version cannot be applied to deuterated acetone. 

The addition of a proton and a phosphine generally proceeded via cis-addition. When 1-octyne was treated with CH3S03H and PPh3 in acetone- in the presence of Pd(PPh3)4, (Z)-l-deutero-l-octen-2-ylphosphonium salt was obtained (Scheme 9). An H-D exchange occurred between sulfonic acid and the deuterated solvent generating deuterated sulfonic acid, which transferred deuterium to the alkyne. 

Kinetic studies on the quaternization reaction of pentamethylpyridine (154A, Scheme 64) and its deuterated congener suggest that there may be an equilibium between this aromatic pyridine and its valence isomer, pentamethyl-Dewar-pyridine (154B). It is known that such valence isomers are stabilized by steric factors such as encountered in pentamethylpyridine.194195 On determining conductometrically the initial rate of quaternization with methyl iodide for polymethylpyridines in acetone, it was found that all but one followed clean bimolecular kinetics. Pen-... 

Unlike ketones and alkenes, aliphatic imines are reluctant to undergo photoinduced (2 + 2) cycyoadditions. For example, the cyclohexanimines of acetone and its derivatives were studied149. Compound 155 undergoes photoaddition with deuterated acetone, but the oxazetidine 156 decomposes to acetone and hexa-deuterioimine 157 (equation 89). 

J. G. Parker and W. D. Stanbro, Optical determination of the collisional lifetime of singlet molecular oxygen in acetone and deuterated acetone, J. Am. Chem. Soc. 104, 2067-2069 (1982). 

Deuterated troponoids, e.g., 32 and 33 [Scheme 9 80BSF(1)327], result from condensations involving mono- or dideuterated diformyl compounds (D enters positions 4 and 8 in 32) and/or perdeuterated acetone (D enters... 

Rotation barriers have also been looked at (80TL1553) in TV-substituted 2,4,6-trimethyI-pyridinium cations (267). In addition to diastereotopic protons HA and HB, the a-Me and (8-protons are anisochronous as shown by HNMR, as are the a-Me, a-ring and /3-ring carbons, as shown by 13C NMR. This anisochronism appears to be due to hindered rotation about the pyridinium N—C bond (268), the stable conformation being that in which the hydrogen atom on the sp3 C is in the plane of the pyridine ring. Observation of coalescence temperatures in deuterated acetone or pyridine solvent allows calculation of energy barriers to this rotation, and these are as follows (267 R = Me, R = H), 7.1 (267 R = Me, R = COMe) (267 R = Et, R = H), 8.1 kJ mol-1. 

Soil Addition of 10 ml water and deuterated standards to 50 g of soil followed by equilibration for 1 h. Sonication 3 times with acetone/ hexane. Phase separation followed by water removal using sodium sulfate, concentration using K-D, and nitrogen blow-down. Spiking with phenanthrene-... 

The binuclear hydride salts are air sensitive, soluble in THF, acetone, CH3CN, MeOH, and diethyl ether, and insoluble in hydrocarbon solvents. They can be stored cold under an inert gas or in vacuo for several months. The salts tend to slowly decompose into W(CO)6 and [PPN] [FeH(CO)4], Carbon monoxide rapidly (within minutes) degrades the dimer into the same products.5 The salts react rapidly with CH3COOD or stronger deuterated acids to form the H-D exchanged products, [FeCrD(CO)9]. The hydrides also act as catalysts in olefin isomerization.10... 

The H/D exchange between the methyl groups of adsorbed acetone molecules and the Bronsted acid sites of zeolite HZSM-5 was also observed upon adsorption of C-2-acetone on a deuterated catalyst (D,HZSM-5, nsi/ Ai = 21.5) at room temperature (Figs 20c and d). The " C MAS NMR spectrum of C-2-acetone adsorbed on zeolite D,HZSM-5 (Fig. 20e) consists of the carbonyl signal at 223 ppm with a featured sideband pattern and a methyl signal at 29 ppm. No significant... 

One of the best procedures for the synthesis of 1,3-diphenylbenzo[c]furan (138) consists of the reaction of 3-phenylphthalide (102) with phenylmagne-sium bromide, 2- especially when the reaction mixture is worked up in the presence of hydroquinone. The primary product can be isolated as colorless crystals with mp 145°C (decomposition above 100°C) in the presence of acid this unstable compound loses water very rapidly. The stereochemistry of the hydroxyphthalan is not known with certainty presumably the cis isomer (137a) is formed first. In deuterated acetone equilibrium with the trans isomer (137b) is established. ° For the synthesis of 1,3-diphenylbenzo [cjfuran, the hydroxyphthalan need not be isolated. 

The H NMR spectra of organic compounds are usually obtained in an aprotic solvent at concentration levels of a few percent. The most widely used solvent is deuterated chloroform (CDC13), sufficiently polar to dissolve most organic compounds. Acetone-r/6 (C3D60), methanol-e 4 (CD3OD), pyridinc-r/5 (C5D5N) and heavy water (D20) are also used. 

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