Alkyl sulfates coupling

Reduction of the C—N bond 0-86 Coupling of alkyl halides (Wurtz) 0-87 Coupling of alkyl halides with or-ganometallic reagents 0-89 Reaction between organometallic reagents and alkyl sulfates or sulfonates... 

Tosylates and other sulfonates and sulfates couple with Grignard reagents, most often those prepared from aryl or benzylic halides.Alkyl sulfates and sulfonates generally make better substrates in reactions with Grignard reagents than the corresponding halides (10-57). The method is useful for primary and secondary R. 

Electrospray ionization. ESI-MS in the negative-ion mode is effective for MS of alkyl sulfates in the surfactant range of C12-C15 chain length (16). The parent ion by itself is not sufficient for unequivocal identification, but this is provided by coupling with LC (31) or by CAD analysis of the parent ion (15). 

The anomeric proton in phenylthio 2,3-dideoxy-hex-2-enopyranosides is sufficiently acidic to enable deprotonation and, for example, reaction of S-glyco-side 68 with BuLi leads to dianion 69 which alkylates or acylates at C (1) from the a-face to give C-glycosides 70 (Scheme 17) [24]. Similarly, deprotonation of hex-2-enopyranoside 71 and coupling with cyclic sulfate 72 provides alkylated product 73 which, upon hydrolysis at pH > 3.5, undergoes a loss of sulfate and a... 

Diazadimethinecyanine dyes are formed by coupling diazotized N-heterocyc-lic amines in the b-position to the nitrogen atom of other heterocycles followed by alkylation. The most important coupling agent is l-methyl-2-phenylindole. Reaction of this compound with diazotized 2-aminothiazole and subsequent methylation with dimethyl sulfate, yields 43, a dye that draws up very quickly on polyacrylonitrile and dyes it a lightfast red shade [102],... 

Diazacyanine dyes with two different alkyl substituents on the triazole nitrogen atoms are obtained by coupling diazotized 3-amino-1-benzyl-1,2,4-triazole to l-ethyl-2-phenylindole and quatemizing the azo dye with dimethyl sulfate or, in the acid pH range, with acrylamide to form the diazacyanine dye [104],... 

The substitution path b) (Eq. (94) ), is favored by the following experimental conditions low current density, grapliite as anode material, alkaline medium, water or water-pyridine as solvent, and admixture of foreign ions e.g., bicarbonate, sulfate, perchlorate, dihydrogen phosphate, Pb2+, Mn2+, Cu2+, Fe2+, Co2+. The carbonium ion path b) can furthermore be expected for carboxylates RR CHOO with a-substituents R such as alkyl, phenyl 198 hydroxy, halogen 1 amino, or alkoxy. These substituents facilitate oxidation of the intermediate alkyl radical R to the carbonium ion R+. Product formation occurs via carbonium ions and not, as is also conceivable, via mixed coupling of R with Nu ... 

Coupling of a benzoic acid derivative under basic conditions is achieved with alkyl iodides," alkyl chlorides,dimethyl sulfate, or (l,1-dihydroperfluoroalkyl)phenyliodonium triflates. Common bases used arc potassium carbonate or sodium hydroxide (with phase-transfer catalyst). " Again, employing acid chlorides " - or anhydrides, " is the method of choice. The reaction can be performed without further activation, " " but in most cases the transformation takes place in the presence of the usual bases, triethylamine - " or pyridine " " " " " [in some cases 4-(dimethylamino)pyridine is added " ]. In a similar manner carbamates. thiocarbamates, " or thiocarbonates are synthesized. Perfluoropropcn-2-ol... 

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