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Grignard reagents with sulphurous acid derivatives

TABLE 8. Formation of sulphoxides, R2S=0, from the reaction of Grignard reagents with sulphurous acid derivatives, SOX2... [Pg.258]

A mixture of 2-t-butylfuran and 2,5-di-t-butylfuran is obtained by the action of t-butyl chloride on furan in the presence of mesitylene nolybdenum tricarbonyl." The intermediate in the nitration of furan-2-aldehyde in acetic anhydride has been identified as compound (26). Treatment of 5-bromo-2-furoic acid with sulphur tetrafluoride in hydrogen fluoride yields the dihydrofuran (27). Bromo-furans are converted into aryl-furans by crosscoupling with aryl Grignard reagents in the presence of nickel(II)-phosphine complexes. 2-Furoic acid is lithiated at position 5, 3-furoic acid at C-2. 2-Methylfuran yields the 5-methylthio-derivative by lithiation and subsequent treatment with dimethyl disulphide. The corresponding phenylthio-compound (28) has been converted into a series of 4-substituted 2-methyl-furans (29 R = alkyl, MeaSi, CO2H, or RCHOH) by the sequence bromi-nation, lithiation, treatment with the appropriate electrophile, and, finally, desulphurization with Raney nickel. 2-Lithiofuran reacts with copper(II)... [Pg.205]

Harder nucleophiles often react with thiirans to give a predominance of attack at carbon, with consequent cleavage of the weak carbon-sulphur bond. This strategy has been used to prepare 7-oxa-4-thia-alk-l-enes from alkoxides, thiiran, and allyl chlorides, yS-mercaptoethyl sulphides from thiiran and thiolate ions, thiazines by the CujO-catalysed cyclization of the adducts of a-lithio-isocyanides with thiirans, tautomeric mixtures of (18) and (19) or (20) from thiiran and hydrazones, 7V-methylpyrrolidines from bis(epithio)linoleic acid and methylamine, and 2,4-dimethylhex-5-ene-2-thiol by addition of the Grignard reagent derived from 3-chlorobut-l-ene with 2,2-dimethylthiiran. Methylthiiran has been found to open... [Pg.210]


See other pages where Grignard reagents with sulphurous acid derivatives is mentioned: [Pg.354]   
See also in sourсe #XX -- [ Pg.257 , Pg.258 ]




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Acid Reagents

Acidic reagents

Grignard derivative

Grignard reagent with acids

Grignard reagents derivatives

Grignard reagents with acid derivatives

Grignard with acid derivatives

Sulphur derivatives

Sulphuric acid

Sulphuric acid derivatives

Sulphurous acids

With Grignard Reagents

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