1.4- Butane sultone

Sulfobutylether P-cyclodextrin is prepared by alkylation of P-cyclodextrin using 1,4-butane sultone under basic conditions. The degree of substitution in P-cyclodextrin is controlled by the stoichiometric ratio of P-cyclodextrin to sultone used in the process. 

In 1996, Sony Corporation found that 1,4-butane sultone (24) (5-50 wt%) can be substituted for EC as a solvent [60] in 1997, Ube Industries, Ltd. discovered that the addition of small quantities of cyclic monosulfonic acid esters (sultones), such as 1,3-propane sultone (PS) (25), suppresses PC decomposition [61]. Furthermore, in 1999, researchers at Ube Industries, Ltd. found that 3-hydroxypropanesulfonic add (26), which is present as an impurity in PS, decomposes at the electrode before PS decomposition and thus adversely affects battery performance by inhibiting the formation of SEI of PS [62] and consequently developed highly pure PS containing little 3-hydroxypropanesulfonic acid (26) [62]. In the same year, Ube Industries found that the combination of small amount of PS (25) and VC (1) can be used as additives [54],... 

The sulfobutylation experiment was conducted in such a way that HNPAEK-xx was dissolved in dry NMP or DMSO and the hydroxyl groups were deprotonated with NaOH first and then reacted with excessive 1,4-butane sultone. General description 1 g HNPAEK-80 (2.59 mmol hydroxyl groups) was dissolved in 20 mL DMSO in a three-necked flask. 0.2 g NaOH (5 mmol) was then added to the solution and the reaction mixture was stirred for 6 h at room temperature. 0.39 g 1,4-butane sultone (2.85 mmol) was then added dropwise to the solution, and the reaction was heated to 160°C, stirred at that temperature for 12 h. The resulting sulfonated copolymers were precipitated in 250 mL acetone and washed by boiling water several times. The obtained polymer was immersed in a large excess of HCl (5 wt.%) solution over 24 h to make the salt form convert into the acid form. The product (SNPAEK-80) was finally dried in a vacnnm at 80°C. 

A reactor containing 4-butane sultone (0.20 mol) dissolved in 150 ml of THE was cooled 70°C and treated dropwise with 21.0 ml of lOM n-butyl lithium followed by... 

SYNS BUTANESULFONE A-BUTANE SULTONE l,4-BUTANESULTONE(MAK) 1,4-BUTYLENE SULFONE A-VALEROSULTONE... 

BUTANE, 2,2 -OXYBIS-(9CI) see BRH760 BUTANESULFONE see BOU250 BUTANE SULTONE see BOU250 A-BUTANE SULTONE see BOU250... 

In addition to the regioselectively derivatized CDs, a number of statistically substituted CDs are in use. Highly water-soluble statistic derivatives are obtained by reaction of CDs with methyl halides [68], with epoxides (e.g., ethylene oxide, propylene oxide [69,70], or allyl glycidylether [71]), and with cyclic sulfates (e.g., butane sultone [72]). Statistical allyl ethers were converted to sulfonates by addition of sulfite [71], Monochlorotriazinyl-P-CD is another available reactive CD. Since these synthetic procedures are rather simple compared to the regioselective ones, many of these statistical compounds are available at the technical scale. 

The rate of hydrolysis of the bicyclic <5-sultone 6153,172 proceeds some 10 times faster than that of the analogous -sultone 62 and some 800 times faster than that of butane sultone as determined by Bordwell and coworkers16,21 reflecting the ability of sulphonate to act as a leaving group from the bridgehead of a bicyclic system. The sultone 61 also reacts readily with pyridine and the sodium derivative of adenine (Scheme 5). 

Both propane sultone and butane sultone have been shown to be mutagenic174 with the former being about forty times more active—consistent with its greater reactivity towards nucleophilic attack as deduced from the rates of hydrolysis16,21. Goldschmidt and his... 

The target product can be obtained by the reaction between L, 4-butane sultone and /3-CD in alkaline solution. Different reaction conditions can have different average DS. Capillary electrophoresis is always applied to analyze the differences in the composition of product mixtiue [9]. 

The formation of the sultone (160) probably involves addition of the complex across the alkene double bond, a 1,2-hydride shift and an intramolecular nucleophilic substitution reaction. The sultone (161) is formed by addition of sulfur trioxide to give the unstable p-sultone which rearranges to the more stable y-isomer (161). Another useful route to sultones is by metallation of alkanesulfonate esters for example, butane-1,3-dimethylsulfonate (162), prepared from butanel,3-diol, yields the 8-sultone, namely 6-methyl-l,2-oxathiin-2,2-dioxide (163) (Scheme 67). 

The rate of hydrolysis of propane sultone in aqueous solution is essentially independent of pH over the pH range 4-9, consistent with a BAL-E1 mechanism (equation 96). At higher pH values, however, in aqueous aprotic solvents the rate of hydrolysis increases and is attributable to an increasing contribution to the overall rate from concurrent bimolecular attack at sulphur (equation 97). Oxygen-18 tracer experiments confirmed that at pH >12, the hydrolysis of propane sultone proceeds with 14% sulphur-oxygen bond fission. The relative rates of hydrolysis at pH > 7 in 65% aqueous acetone of five-membered six-membered open-chain sulphonates (propane sultone, butane-1,4-sultone and of ethyl ethanesulphonate) were found to be 37 1 7126. The enthalpies of activation of all three compounds were very similar and the difference in rates were attributed to differences in entropies of activation ( — 17.1, —24.0 and —17.9 e.u., respectively). These data, however, are composite values. It is not possible to compare the kinetic acceleration for attack at sulphur in aliphatic sultones because both the six-membered sultone and the open-chain sulphonate hydrolyse exclusively with carbon-oxygen bond fission, within the limits of experimental detection. 

The N-nitroso derivatives of propane sultam, butane sultam and pentane sultam were synthesized from the parent compounds (equation 230). N-nitrososultams decompose thermally in aqueous solution to form the corresponding sultones. However, just as in the case of sulphonamides, unless bases are present, a variety of reaction products are formed as a result of various (acid-catalysed) side-reactions. Reproducible rates of decomposition... 

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