Benzenesulfonyl chlorides, hydrolysis

These micellar charge effects also seem to be present for reactions at heteroatoms. For example, in the spontaneous hydrolysis of a series of benzenesulfonyl chlorides (12), values of k+/k for reactions in CTAC1 and SDS increase from 0.85 for X = OMe to 22 for X = NOz, suggesting that there is a substituent effect upon the relative extents of bond-making and breaking (Bunton et al., 1985). 

General base (jSnuc = 0.19) and nucleophilic catalysis mechanisms have been established for the hydrolysis of benzenesulfonyl chloride. Two-parameter LFERs were found for each route and electronic effects were seen to be greater than steric.272... 

Studies of the spontaneous hydrolysis of a series of substituted benzoyl chlorides and of 4-X-benzenesulfonyl chlorides at 25 °C in cationic, anionic, and sulfobetaine micelles have allowed an assessment to be made of micellar charge effects on hydrolysis mechanisms.72... 

Methanesulfonyl chloride is the largest-volume alkanesulfonyl chloride. Benzenesulfonyl chloride is the only aromatic sulfonyl halide with significant commercial production, primarily as a feedstock for the manufacture of A-butyl benzenesulfonamide. All sulfonyl chlorides are poorly water soluble, which limits their hydrolysis except at elevated temperatures or in the presence of a homogenizing agent such as a cosolvent, surfactant or phase-transfer agent. 

Formation of adduct 23 is usually less of a problem with tertiary oryZamines because of their lesser nucleophilicity and lower solubility as compared to trialkyl amines. Consequently, the competing hydrolysis of benzenesulfonyl chloride by hydroxide ion (Eq. 25.55) allows recovery of most of the amine. However, this class of amines is often subject to other side reactions that produce a complex mixture of... 

Theoretical studies of the gas-phase hydrolysis or methanolysis of methylsul-fonyl chloride indicated a concerted Sn2 process involving a four-membered cyclic transition state. The tertiary amine-catalysed hydrolysis of benzenesul-fonyl chloride was shown to be inhibited by chloride ion and a nucleophilic mechanism of catalysis was favoured. Kinetic studies" of the solvolysis of p-substituted benzenesulfonyl chlorides in aqueous binary mixtures with acetone, methanol, ethanol, acetonitrile and dioxime showed that the reactions were third order processes, with first order rate constants determined mainly by the molar concentrations of the protic solvent, so that the reaction rates appear to be dominated by solvent stoichiometry. The solvolyses in methanol and ethanol yield both an alcoholysis (ap) and a hydrolysis product (hp). Solvolyses of electron-rich arylsulfonyl chlorides, under neutral or acidic conditions, exhibited surprising maxima in solvent-dependent S values as defined by Equation 15. 

These effects were hidden in previous studies, which were restricted to hydrolysis in mixtures with aprotic solvents or in sulfuric acid where only one product is obtained. The experimental data indicated changes in reaction mechanism depending on water content and solvent polarity. In agreement with previous studies, they indicated the operation of two simultaneous reaction channels in the different media used, with an SNl-type reaction favoured in more aqueous media. In the methanolysis of p-substituted benzenesulfonyl chlorides in various solvent combinations, the mechanism appeared to consist of a mixture of the SnI and Sn2 reaction pathways, but in methanol-ethylene glycol mixture, the results favoured the Sn2 mechanism. ... 

The preparation of monoalkyl derivatives of diamines represents something of a synthetic problem. Procedure 13-3 involves acetylation of ethylenediamines under mild conditions to the monoacetyl ethyl-enediamine, protection of the second amino group by a Hinsberg reaction with benzenesulfonyl chloride, followed by N-alkylation of the acetamido group, and recovery of the iV-alkylethylenediamine by acid hydrolysis [15]. 

The aromatic sulfonyl chlorides which have no a-hydrogen and thus cannot form sulfenes give acylic sulfones. Thus 1-piperidinopropene on reaction with benzene sulfonyl chloride (9J) gave 2-benzenesulfonyl-l-piperidinopropene (153). Similarly the enamine (28) reacts with p-toluene-sulfonyl chloride to give the 2-p-toluenesulfonylcyclohexanone (154) on hydrolysis (/OS). 

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