Preparation of $N$-alkylmethanesulfonimidamides and study of their adducts with menthone
Abstract
The reaction of N-tosylmethanesulfonimidoyl chloride, obtained by condensation of methanesulfinyl chloride with Dichloramine-T, with secondary aliphatic amines resulted in the formation of N-tosylsulfonimidaides (MeSO(:NTs)NR$\sb2$). Tosyl cleavage was achieved upon treatment with sodium anthracenide and resulted in the formation of methanesulfonimidamides (MeSO(:NH)NR$\sb2$). The tosyl group in S,S-dialkyl-N-tosylsulfoximines (R$\sp1$SO(:NTs)R$\sp2$) could also be cleaved with sodium anthracenide. Sulfonimidamido carbamates and ureas were prepared by reaction of methanesulfonimidamides with, respectively, alkyl (ethyl or menthyl) chloroformate and phenyl isocyanate. Phase transfer catalyzed N-alkylation of methanesulfonimidamide potassium anions, obtained from potassium hydride, was performed by reaction with primary alkyl bromides and catalytic amounts of tetraalkylammonium--or phosphonium--salts. Leaving group effect, metal hydride effects, and solvent effects were studied. N-Butyl and N-benzylmethanesulfonimidamides derived from morpholine, pyrrolidine, piperidine and dibutylamine, as well as their S-phenylsulfoximine analogs were added to l-menthone via their lithium anions. In these additions, sulfonimidamides and sulfoximines were found to give comparable yields and product distributions. Study of the separation of the menthone adducts was achieved by comparing their TLC rate factor (R$\sb{f}$) ratios ($\alpha\sb{\rm TLC}$). IR analysis of the separated menthone adducts showed the diastereomers with a higher R$\sb{f}$ to be intramolecularly H-bonded. This was not observed in the diastereomers with a lower R$\sb{f}$. A conformational model whereby the observed and hypothetical intramolecular H-bond containing six-membered rings assume their most stable conformations allowed correlation of the configuration at sulfur with the stereocenters of the menthyl ring. An X-ray crystallographic analysis confirmed the sulfur absolute configuration assignment based on the conformational model. Application of the conformational model to the stereoselectivity of the addition of sulfoximine and sulfonimidamide lithium anions to menthone was discussed. Thermal treatment of isolated menthone adducts gave enantiomerically enriched N-alkylmethane-sulfonimidamides whose optical purity depended on the diastereomeric purity of the corresponding isolated $\beta$-hydroxysulfonimidamide precursors. ^
Subject Area
Chemistry, Organic
Recommended Citation
Olivier Lavergne,
"Preparation of $N$-alkylmethanesulfonimidamides and study of their adducts with menthone"
(January 1, 1989).
ETD Collection for Wayne State University.
Paper AAI8922764.
http://digitalcommons.wayne.edu/dissertations/AAI8922764