Dialkyl alkylation

Oxetane, 2-(o -chlorobenzyl)-2-phenyl-X-ray crystal structure, 7, 366 Oxetane, 3-chloromethyl-3-ethyl-ring strain, 7, 370-371 Oxetane, 2-(o-chlorophenyl)- H NMR, 7, 367 Oxetane, 2-cyano-synthesis, 7, 391-392 Oxetane, 2-cyano-3,3-dimethyl-2-phenyl-thermolysis, 7, 372 Oxetane, 2,2-dialkoxy-synthesis, 7, 396 Oxetane, 2,2-dialkyl-isomerization, 7, 377 Oxetane, 3,3-dialkyl-alkylative cleavage, 7, 381 polymers, 7, 382 Oxetane, 2-diethylamino-synthesis, 7, 390 Oxetane, 3,3-difluoro-molecular dimensions, 7, 365 Oxetane, 2,2-dimethyl-mass spectra, 7, 368-369 photolysis, 7, 373 synthesis, 7, 393 Oxetane, 2,3-dimethyl- H NMR, 7, 366 thermolysis, 7, 372 Oxetane, 2,4-dimethyl-mass spectrum, 7, 369... 

In dibenzothiophene-S,S-dioxide the S atom is in a ring, and hence more constrained. The yield of SOz in the radiolysis is linear with the dose to about 13 Mrad after which it levels off as in p,p -ditolyI sulfone. However, the yield of S02 in this case is much lower (a factor of 25) than in the case of p,p -ditolyl sulfone (G = 0.002 compared to G = 0.05). This stability of the dibenzothiophene sulfone could be partially due to back reaction to reform the parent sulfone and partially due to more efficient energy delocalization. The expected biphenylene product was not detected due to limitations of the analytical method. Bowmer and O Donnell70 studied the volatile products in y-radiolysis of dialkyl, alkyl aryl and diaryl sulfones. Table 2 gives the radiolytic yields of S02 and of the hydrocarbon products of the alkyl or aryl radicals. The hydrocarbon products are those obtained either by H atom abstraction or by radical combination. The authors69 suggested the mechanism... 

Other racemization systems that may be amenable to conversion to deracemization processes in future have recently been reported by Faber and coworkers [33]. Resting cells of L. paracasei have been used for biocatalytic racemization of open-chain and cyclic dialkyl-, alkyl-aryl-, and diaryl-substituted acyloins (29/30) (Figure 5.20). Both... 

Water insoluble tetrabutylammonium metaperiodate, which can be prepared from sodium metaperiodate and tetrabutylammonium hydrogen sulphate in aqueous solution, was found to be a useful reagent for the selective oxidation of sulphides in organic solvents . The reaction was generally carried out in boiling chloroform and gave dialkyl, alkyl aryl and diaryl sulphoxides in yields which are comparable with those reported for sodium metaperiodate in aqueous methanol solution (Table 4). In the case of diaryl sulphoxides, the yields decrease with prolonged reaction time. 

Andersen (75,76), as well as Mislow (221), discovered that the ORD curves of alkyl aryl sulfoxides show a strong Cotton effect in the region below 250 nm. An extensive study by Mislow and his coworkers (47) led to the following empirical rules, correlating the sign of the Cotton effect with the absolute configurations of chiral dialkyl, alkyl aryl, and diaryl sulfoxides, as well as menthyl esters of aromatic sulfinic acids ... 

Steric effects dominate in the oxidation of dialkyl, alkyl phenyl and benzal methyl phenyl sulfides to their sulfoxides by quinolinium fluorochromate (QFC) in aqueous acetic acid. QFC oxidation of phenoxyacetic acids has been smdied. Imidazolium dichromate oxidations of a-hydroxy acids have been smdied. ... 

Due to a much lower danger of dialkylation, alkylation of iV-alkyl- and Ai-alkyl-O-protected hydroxylamines (e.g. 8, equation 6) with primary alkyl halides proceeds substantially more selectively giving high yields of Al,Al-disubstituted products " of type 9. 

Diagnostic agents classification, 36 6-7 inorganic, 36 5-6 Diagonal twist, 34 253-254 Dialkyl alkyl phosphonates, in liquid-liquid extraction, 9 29... 

The synthesis of quinazoline derivatives by the addition of N(3)-C(4) fragment units has not previously been a major synthetic route, but 2,4-dialkyl, alkyl/aryl, and diaryl quinazolines 865 are now readily available by a new procedure that involves activation of A -arylamides 864 with trifluoromethanesulfonic anhydride and 2-chloropyridine, and subsequent addition of nitriles <2006JA14254>. Either normal or microwave heating can be used to perform the final ring-closure step. 

S. Lang-Fugmann u. S. Pawlenko Dialkyl-, Alkyl-aryl-diazen-l-oxide... 

Various dialkyl, alkyl aryl and diaryl sulfoxides were readily oxidized to the corresponding sulfone in excellent yields under mild conditions at — 30 °C by 51243. Interestingly,... 

Dialkyl-, Alkyl-aryl- und Diaryl-thiophosphinsaure-chloride konnen in ausgezeichneten Ausbeuten aryliert werden. Unsymmetrisch substituierte tert.Phosphansulfide sind so in einfacher Weise leicht zuganglich52. ... 

Dialkyl, alkyl aryl, and diaryl tellurium dichlorides were reduced by thiourea dioxide in a 2 molar aqueous solution of sodium hydroxide to the corresponding diorgano tellurium compounds4,5. The tellurium species actually reduced are the diorgano tellurium oxides or dihydroxides that are formed from the dichlorides in the basic medium. 

Diorgano tellurium dihalides were prepared in this manner from dialkyl, alkyl aryl, and diaryl tellurium compounds, and from tellurium heterocycles. However, 1-oxo-1,3-dihydro-2-benzotellurophene experienced ring cleavage when reacted with sulfuryl chloride7. 

Finally, the sulfinates were transformed to o.p. sulfoxides by treatment with either Grignard or organolithium reagents. The presence of a free hydroxyl group in the sulfmate esters involves the use of two molar equivalents of the organometallic in THF at room temperature. Various dialkyl, alkyl aryl, and diaryl sulfoxides have been obtained in quantitative yield and in 100% ee (Table 12). 

As for the amine moiety, the rearrangement has been demonstrated (although not unequivocally in all cases) for mono-A -substituted glycosyl-amines derived from aromatic amines and aralkyl- and alkyl-amines and for di-A-substituted glycosylamines containing dialkyl, alkyl-aryl, aralkyl, isocyclic, and heterocyclic alkyl radicals. The rearrangement has been reported for A-glucosyl derivatives of amino acids, but not as yet... 

Dialkyl, diaryl, unsymmetrical dialkyl, alkyl aryl, and unsymmetrical diaryl telluriums served as the tellurium-containing starting materials (Vol. IX, p. 1075). The reactions with methyl iodide and low molecular mass organic bromides proceed at 20° in organic solvents such as chloroform and methanol or in mixtures of the neat reagents.With aryl telluriums several days are required for completion of the reaction. Diaryl telluriums with ortho-substituents react only with difficulty. Bis[2,4,6-trimethylpheny 1] tellurium did not combine with methyl iodide. The reactions with ethyl iodide and a-bromocarboxylic acids are accelerated by gentle heating. 

Dialkyl, alkyl aryl, and diaryl trithiocarbonates are reduced in DMF to the radical anion, which loses a thiolate ion [146-148]. The rate of the cleavage was measured with CV for substituted diphenyltrithiocarbonates, the rate constant of the cleavage was found to vary linearly with Hammett s substituent constant a. The anion radicals of mono- and... 

Fukuto TR. Toxicological properties of trialkyl prosphorothionate and dialkyl alkyl- and arylphosphonothionate esters. J Environ Sci Health B 1983 18(1) 89 117. 

Hydrocarbons, dialkyl alkyl-phosphonates, alkyl alkyl-phosphonic acids... 

The Michaelis-Arbuzov procedure, illustrated in general terms in reaction 16, has been used extensively to prepare dialkyl [alkyl(or aryl)thiomethyl]phosphonic diesters " (2-Alkylthioethynyl)phosphonic diesters (375) were prepared from RSC CCl ", whilst the esters 376 and 377 were obtained in an analogous fashion, the latter being a useful... 

Phosphonate carbanions (97), generated by the addition of various carbanions to vinylphosphonates, provide routes to functionalized alkenes. Thermolysis of the dienes (98) prepared in this way offers a route to 1,4-disubstituted benzenes via electrocyclization of the intermediate trienes (99) (Scheme 17). The reaction of phosphonate carbanion (100) with alkyl or aryl benzenethiosulphonates provides a general synthesis of the useful dialkyl alkyl- and aryl-thiomethyl-phosphonates (101). ... 

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