Sulfones, alkylation reagents

A iridine traces in aqueous solution can be determined by reaction with 4-(p-nitroben25l)pyridine [1083-48-3] and potassium carbonate [584-08-7]. Quantitative determination is carried out by photometric measurement of the absorption of the blue dye formed (367,368). Alkylating reagents interfere in the determination. A iridine traces in the air can be detected discontinuously by absorption in Folin s reagent (l,2-naphthoquinone-4-sulfonate) [2066-93-5] (369,370) with subsequent chloroform extraction and hplc analysis of the red dye formed (371,372). The detection limit is ca 0.1 ppm. Nitrogen-specific thermal ionisation detectors can be used for continuous monitoring of the ambient air. 

The principal electrophiles to attack ring sulfur are either oxidants or alkylating reagents. Thiophene sulfoxide and sulfone formation is discussed in Section 3.02.2.6. Alkylating agents capable of forming thiophenium salts include trimethyloxonium tetrafluoroborate (MeaO BF ) and alkyl fluorosulfonates (ROSO2F). The salts e.g. 87) are conveniently isolated as hexafluorophosphates (88). 

The syntheses of iron isonitrile complexes and the reactions of these complexes are reviewed. Nucleophilic reagents polymerize iron isonitrile complexes, displace the isonitrile ligand from the complex, or are alkylated by the complexes. Nitration, sulfonation, alkylation, and bromina-tion of the aromatic rings in a benzyl isonitrile complex are very rapid and the substituent is introduced mainly in the para position. The cyano group in cyanopentakis(benzyl isonitrile)-iron(ll) bromide exhibits a weak "trans" effect-With formaldehyde in sulfuric acid, benzyl isonitrile complexes yield polymeric compositions. One such composition contains an ethane linkage, suggesting dimerization of the transitory benzyl radicals. Measurements of the conductivities of benzyl isonitrile iron complexes indicate a wide range of A f (1.26 e.v.) and o-o (1023 ohm-1 cm.—1) but no definite relationship between the reactivities of these complexes and their conductivities. 

Reduction of alkyl halides and sulfonate estersThis reagent in HMPT is Nomcwhat more effective than NaBH3CN for reduction of primary alkyl iodides and allylic and benzylic iodides. It is also preferred for reduction in benzene or CH2C12. 

Perfluoroalkyl(phenyl)iodonium sulfonates 42 (also known as FITS reagents), as well as lFf,lff-perfluoroalkyl(aryl)iodonium triflates 44, have found practical application as electrophilic fluoro alkylating reagents toward a... 

Alkyl halides and alkyl sulfonates have been generally used as alkylating reagents. An example of the conversion of an alcohol into a primary amine by the Gabriel synthesis is shown in Scheme 37. ... 

Both anionic and cationic type long-chain reagents are widely used in flotation as collectors. These include carboxylates, alkyl sulfonates, alkyl sulfates, alkyl amines and ehelating agents. Most minerals, except sulfides, require long-ehain eolleetors for their flotation. The behavior of long-chain collectors in solution is determined by the properties of the polar heads and hydrophobic tails and their resultant solvent power. 

The reagents (R = CH3, C2HS) react with activated arenes without Friedel-Crafts catalysts to form alkyl aryl sulfones. Alkylation rather than sulfonylation is observed when R = CH(CH3)2. Sulfonylation involves the sulfonylium ion RSO2 when R is a secondary alkyl group the ion readily loses SO2 to give the carbonium ion. ... 

Starting materials for the preparation of these snrfactants are alkylatable N-compounds (long-chain alkylamines) and alkylation reagents such as sodium chloroacetate, acrylic acid, and sodium chloro hydroxypropane sulfonate. 

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