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Two modular and highly convergent approaches for the synthesis of both isomers of a large number of optically pure C(2)-symmetric bis-sulfoxides have been developed, and their scope and limitations have been assessed. The first one uses as intermediate diastereomerically pure C(2)-symmetric bis-sulfinate esters 6(S(S),S(S)) and 6(R(S),R(S)), obtained by dynamic kinetic resolution of ethane-1,2-bis-sulfinyl chloride 5. A single inducer of chirality, the glucose-derived DAG (diacetone-D-glucose) 1 is used for the enantioselective synthesis of both diastereomerically pure C(2)-symmetric bis-sulfinate esters, thanks to the opposite stereodirecting effect of pyridine and (i)Pr(2)NEt used to catalyze the reaction. The second approach is based on the copper-catalyzed oxidative coupling of optically pure lithiomethyl sulfoxides. Both isomers of a large number of methyl sulfoxides can be obtained in a convergent manner using (R(S))- and (S(S))-DAG methanesulfinate esters 8R(S) and 8S(S). Methanesulfinates 8R(S) and 8S(S) are also obtained in an enantioselective way by a dynamic kinetic resolution of methane sulfinyl chloride 24. The final bis-sulfoxides are obtained with enhanced enantioselectivities compared to the corresponding monomers, as a result of the Horeau effect which is operating in both approaches. A model based on the formation of pentacoordinated sulfur intermediate is proposed. This model can explain the dynamic kinetic resolution observed via Berry pseudorotations, without the commonly accepted in situ racemization of the starting material. The usefulness of the approaches is demonstrated by the preparation of complexes of Pd(II) and Ru(II) bearing bidentated chiral sulfoxides as ligands.

Diacetone- D -glucose (DAG) reacts with t -BuSOCl in the presence of NEt 3 and Py to give (−)-( S )- and (+)-( R )- tert -butanesulfinate respectively, in high diastereomeric excess. These sulfinates were transformed into various enantiomerically pure tert -butyl sulfoxides by reaction with different Grignard reagents. Additionally, the reaction of tert-butylmagnesium chloride with (+)-( R )- and (−)-( S )-methanesulfinates of DAG has been found to occur with complete inversion of configuration and not with retention as previously reported.

N-Propargylsulfeneamides 2-5 and N-propargylmethanesulfineamides 6 and 7 have been synthesized from N-propargylamines 1 and sulfenyl halides or methylsulfinyl chloride, respectively. In a similar way, propargylmethanesulfinates 8 and 9 have been obtained from the corresponding propargyl alcohols and methylsulfinyl chloride. The IR spectral study on the existence of intermolecular and/or intramolecular hydrogen bonds in S-containing propargyl compounds 6-9 has been carried out.

An improved method for the separation and purification of azetidinyl methyl sulfinates is described. This method utilizes a Waters preparative high-performance liquid chromatographic set-up. The methyl sulfinate isomers are isolated in high purity and no double bond isomerization is observed to occur. The diastereomers eluted from both the analytical and preparative columns at approximately the same retention times under the conditions used in the method.

Sulfinyl chlorides were prepared in good to excellent yields by reacting aryl or alkyl 2-trimethylsilylethyl sulfoxides with SO2Cl2.

Synthese de dimethyl-1,1 ethanesulfonate et de (diphenyl-1,1 trifluoro-2,2,2) ethanesulfonate de neopentyle, nitro-4 phenyle, et de dioxabicyclooctyle

Agelasidine A was synthesised based on the strategy modelled on the hypothesis of biosynthesis; this strategy provided an efficient three-step synthesis of agelasidine A from farnesol.