J. F. King

An easy preparation of simple sultines and hydroxyalkanesulfinate salts

Abstract In accord with mechanistic prediction a one-pot, two-stage, controlled chlorination-hydrolysis of HO(CH 2 ) n SH gave the sultine when n = 3 or 4, and the polymeric sulfinic ester when n = 5 or 6; alkaline hydrolysis of either product yielded the corresponding sodium ω-hydroxy-1-alkanesulfinate.

Mechanisms of reactions of sulfonyl compounds with nucleophiles in protic media

The mechanism ofthe reaction of ethylene sulfone (thiirane 1,l-dioxide) with hydroxide in water and methoxide in methanol, been examined. Evidence has been obtained for two distinct pathways (respectively first order and second order in hydroxide), which are believed to proceed has via attack of hydroxide on the sulfone to give a trigonal-bipyramidal monoanion which reacts either with water or with another hydroxide ion to form ethanesulfonate anion or ethylene plus sulfite anion in quite different proportions. Study of the mechanisms of hydrolysis of alkanesulfonyl chlorides has been extended to (a) cyclopropanesulfonyl, (b) trimethylsilylmethanesulfonyl, (c) tris- (trimethylsily1)-methanesulfonyl, (d) 2,2,2-trifluoroethanesulfonyl, and (e) 2-methyl-2- propanesulfonyl chlorides. The last hydrolyzes by initial t-butyl cation formation, while the others go by more or less precedented routes, usually by way of a sulfene. Reactions of arenesulfonyl chlorides with a number of primary and secondary amines show pH-yield profiles indicating third-order processes to the sulfonamide at high pH. The propensity for third-order reactivity increases with increasing hydrophobic character of the alkyl group(s). A practical result is that a number of amines are efficiently converted into their benzenesulfonamides using only a slight (5%) excess of benzenesulfonyl chloride in 1 M NaOH. For a number of years we have been interested in the study of the mechanisms of reactions of the sulfonyl group, particularly those processes which lead to overall nucleophilic substitution. This paper presents three related topics each of which deals with the reactions of nucleophiles with a sulfonyl group in water. The specific topics, involve 1) ethylene sulfone and the final stage of the Ramberg-Blcklund reaction, 2) the hydrolysis of alkanesulfonyl chlorides, and 3) new mechanisms of reaction of arenesulfonyl chlorides with nucleophiles. 1. The Ramberg-Backlund reaction and the reactions of ethylene sulfone with nucleophiles The general course of the well-known Ramberg-Backlund reaction is shown below.

ω-HYDROXY-1-ALKANESULFONYL CHLORIDES

Abstract The general synthesis of hydroxyalkanesulfonyl chlorides is illustrated by the preparation of 6-hydroxy-1-butanesulfonyl chloride (2e) and 5-hydroxy-1-pentanesulfonyl chloride (2d) as fairly stable, oily liquids (of ∼95% purity) characterized by 1Hmr, 13Cmr and infrared spectra, and by conversion both to the corresponding sultones (3) and to crystalline acetoxy-piperidides (6); 2d and 2e form apparent polymers, very slowly on standing at room temperature and more rapidly on heating, but on reaction with triethylamine yield the sultones (3d and 3e). A sample consisting mostly (>70%) of 4-hydroxy-1-butanesulfonyl chloride (2c), prepared and characterized similarly, was found to form the sultone (3c) slowly in non-polar solvents, much more readily in polar media (t ½ ∼20 min in water), and very rapidly in the presence of triethylamine. Effective concentrations for the spontaneous cyclization of 4-hydroxy-1-butanesulfonyl chlorides (2c) and the tertiary-amine induced cyclizations of 2d and 2e are est...

Alkylation of sulfonate anions via substrate-reagent ion-pair (srip) reactions of [2]betylates. Preparation of alkyl esters of hydroxyalkanesulfonic acids

[2]Bety1ate sulfonates (4 or 8) give alkyl sulfonate esters (6) in refluxing toluene or benzene, chiral esters being formed with inversion. Preparation of alkyl hydroxyalkanesulfonates in this way (a) is a simple route to a little-known class of compounds, and (b) shows sulfonate anions to be more nucleophilic than hydroxyl groups in this system.

HYDROXYALKANESULFONYL CHLORIDES FROM CHLORINATION OF HYDROXYALKANESULFINATE SALTS IN A NONPOLAR MEDIUM: 3-HYDROXY-1-PROPANESULFONYL AND 4-HYDROXY-1-BUTANESULFONYL CHLORIDES

Abstract 3-Hydroxy-1-propanesulfonyl chloride (1b) was obtained for the first time (admixed with 10% of propane sultone, 2b) by chlorination of a dichloromethane suspension of sodium 3-hydroxy-1-propanesulfinate (3b). 4-Hydroxy-1-butanesulfonyl chloride (1c) containing 13% butane sultone (2c) was prepared similarly from 3c. The cyclizations of 1b and 1c in CDCl3 containing 1-butanol (0.9 M) showed first order rate constants of 1.4 × 10−4 and 6.4 × 10−5 s−1, corresponding to effective concentrations of 4.5 × 102 and 2.1 × 102 M, respectively. Reaction of triethylamine in ethanol-d (a) with 1b gave exclusively the undeuterated sultone (2b), evidently by a direct cyclization, and (b) with 1c produced mainly ethyl 4-hydroxy-1-butanesulfonate largely monodeuterated at the α-position, and presumably formed by way of the sulfene (6c).

The resistance to hydrolysis of N,N-dimethyl-N-phenylammoniomethanesulfonate and the improbability of a recently-proposed mechanism of hydrolysis of anilinomethanesulfonates

Abstract The hydrolysis of PhN+Me2CH2SO3− (2) is so slow that a proposed mechanism of hydrolysis of PhNHCH2SO3− Na+ involving SN2 attack of H2O on PhN2+CH2SO3− may be discounted.

The mechanism of biomolecular methyl transfer in a methyl aminoalkanesulfonate. application of 18o isotope shifts in 13cmr spectra of sulfonic esters.

Abstract 13Cmr spectra show complete absence of scrambling of an 18O label in 1 a recovered after partial conversion to 2 a thereby precluding an 0 -methylation mechanism for the bimolecular formation of 2 a from 1 a .

Stereochemistry of two-phase and substrate-reagent ion-pair reactions of betylates: complete inversion in the synthesis of halogen, sulfur, and nitrogen derivatives from R-(-)-2-octanol

Abstract Conversion of a chiral secondary alcohol into a chiral halogen, sulfur or nitrogen derivative may be conveniently carried out by way of a “betylate” ester. The overall reaction gives reasonable (40–40%) yields with high stereoselectivity (100% inversion in seven or eight examples).

THE EFFECT OF LOCATING THE SULFONYL GROUP IN A FIVE-MEMBERED RING ON THE BALANCE OF ELIMINATION VS. SUBSTITUTION REACTIONS OF SULFONIC ACID DERIVATIVES

Abstract The simplest examples of both a five-membered cyclic sulfonic anhydride (ethane-1, 2-disulfonic anhydride, 3) and a sulfonylammonium salt (2, 2-dimethylisothiazolidinium 1, 1-dioxide fluorosulfate, 13), are found to react with triethylamine and an alcohol via direct displacement at sulfur and not by way of the sulfene. When taken with previous observations these results lead to the conclusion that five-membered cyclic sulfonic acid derivatives can generally be expected to react entirely by direct displacement, even in those reactions in which the acylic or six-membered cyclic analogues react entirely via the sulfene.

MECHANISTIC VARIATION IN ALKANESULFONYL CHLORIDE HYDROLYSIS AND RELATED REACTIONS

Abstract Kinetic and product ratio studies are consistent with the following mechanisms for the hydrolysis of methanesulfonyl chloride: (a) in acidic medium (pH 1–6) via a direct substitution on sulfur (SN 2-S), (b)in mildly basic medium (pH 8–10) by way of sulfene (CH2=SO2) formation followed by trapping with water, and (c) in strongly basic solution (pH > 10) via sulfene with trapping by the hydroxide ion. The reactions of primary and secondary alkanesulfonyl chlorides are qualitatively similar.