- Synthesis of Aromatic and Olefinic Sodium Sulfonates by Electrophilic Destannylation with Trimethylsilyl Chlorosulfonate
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A mild and effective method for the preparation of a variety of aromatic, olefinic, and acetylenic sodium sulfonates is described.The reaction of trialkylaryl- (2a-k) and -heteroarylstannanes (4a-d), bis-(1-alkenyl)dibutylstannanes (6a-f), or trialkylakynylstannanes with trimethylsilyl chlorosulfonate (1) followed by hydrolysis with aqueous NaHCO3 provides the sodium sulfonates in an ipso-specific and in the case of vinylic stannanes stereospecific manner.A comparision of the reactivity of stannylated and silylated olefinic compounds 13 and 14 underlines the greater leaving ability of the stannyl moiety.The in situ preparation of the stannanes makes it possible to apply the synthetic method to natural products such as N-substituted apocodeine (17). - Key Words: Electrophilic aromatic substitution/ Electrophilic vinylic substitution/ Trialkylstannanes, application of/ Arylsulfonates, sodium salts of/ Vinylsulfonates, sodium salts of
- Niestroj, Michael,Lube, Andreas,Neumann, Wilhelm P.
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p. 575 - 580
(2007/10/02)
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- Sulfosilylation of Aromatic Hydrocarbons by Trimethylsilyl Chlorosulfonate
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Aromatic hydrocarbons 2 ,6 ,8 ,9 ,13 ,16 ,18 ,19 ,22 react with trimethylsilyl chlorosulfonate (1) to give trimethylsilyl arenesulfonates 5, 7, 11, 12, 15, 23 or sulfonic acids 17, 20, 21.If trimethylsilyl sulfonates are obtained, working up of the sulfonation mixtures is possible by distillation.By hydrohalogenolysis of trimethylsilyl sulfonates 5 at 0-5 deg C anhydrous sulfonic acids 3 result.The pathways to diphenylsulfone (25a) in the reaction of benzene (2a) with 1 were investigated.In this connection we succeeded in synthesizing benzenepyrosulfonic acid (28) and trimethylsilyl benzenepyrosulfonate (29).
- Hofmann, Karin,Simchen, Gerhard
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p. 282 - 297
(2007/10/02)
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- Le sulfate de bis (trimethylsilyle) reactif de sulfonation en chimie organique
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Trimethylsilyl chlorosulphonate 1 and di-(trimethylsilyl) sulphate 2 are obtained by reacting trimethylchlorosilane with chlorosulphonic acid and sulphuric acid respectively. 1 and 2 are thermally stable and soluble in most of the organic solvents.The silyl sulphonates are hydrolyzed at room temperature. 2 is less reactive than 1 and is adequate reagent when the molecule contains ether or ester groups as 1 reacts also as chlorination reagent.Thus, 2 when refluxed in the presence of an excess of methoxy benzene gives quantitatively trimethylsilyl 4-methoxybenzenesulphonate 3 which is hydrolyzed quantitatively into 4-methoxybenzenesulphonic acid. 2 reacts with acid chlorides and acid anhydrides in refluxing cyclohexane or carbon tetrachloride which leads to α-sulphonic carboxylic acids 4 by sulphonation in position α to the acyl function.When starting from chloroacetylchloride, a gem-disulphonic derivative 5 is formed.A common intermediate, acyl and trimethylsilyl sulphate 6, is put forward and easy preparation and isolation of sulphonic acids by this method is pointed out.
- Bourgeois, Paul,Duffaut, Norbert
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p. 195 - 199
(2007/10/02)
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