Six‐membered cyclic sulfites derived from glucofuranose and 1,2,4‐butanetriol

Abstract

Six-membered cyclic sulfites derived from glucofuranose derivatives 5, 6 and from 1-O-tert-butyldimethylsilil-1,2,4-butanetriol 12 were synthesized and separated into pure diastereomers which were in turn subjected to the sequence of reactions leading to the introduction of the terminal vinyl ether fragment. Reactivity and applicability of cyclic sulfites as intermediates in [2+2]cycloaddition of chlorosulfonyl isocyanate (CSI) to vinyl ethers were studied. The cycloaddition to vinyl ethers 19 and 20 proceeded in low yield and low asymmetric induction, in the case of the former, and moderate yield and pronounced asymmetric induction, in the case of the latter. The (1)H-NMR spectra of sulfites 13-16 reveal a preference of the sulfite oxygen atom for the axial position. Thus, well-defined conformation in solution for compounds 13 and 15 and a mixture of the two possible chair forms for sulfites 14 and 16 could be assigned. The stretching frequency of the S-->O bond in stable conformation with an axial sulfite oxygen occurs in the range 1,160-1,210 cm(-1), whereas conformationally mobile sulfites exhibit corresponding absorption above 1,220 cm(-1). The absolute configuration assignments of sulfites 7, 8, 15, 16 and 25-28 were done empirically based on the combined analysis of the NMR, IR, X-ray, and dichroic data. It was demonstrated that the sign of the Cotton effect around 194 nm correlated with the absolute stereochemistry at the sulfur atom in a sulfite chromophore.

Diastereoisomerically Pure, (S)-O-1,2-O-isopropyli dene-(5-O-α-d-glucofuranosyl) t-butanesulfinate: Synthesis, Crystal Structure, Absolute Configuration and Reactivity

“…; 1 H NMR (CDCl 3 ): 2.28 (s, 3H); 1.15 (s, 9H). These data are fully consistent with the literature data [ 25 , 28 ].…”

“…Having in the hands diastereomerically pure ( R )-1,2- O -isopropylidene-3,5- O -sulfinyl-α- d -glucofuranose ( R )- 4 , synthesized from α- d -glucofuranose in the sequence of reactions, described earlier by one of us [ 28 ], we decided to check if its reactions with Grignard reagents could be stopped at the stage of the corresponding sulfinic acid esters. Reactions of 4 with methylmagnesium iodide 7a , phenylmagnesium bromide 7b , and p -tolylmagnesium bromide 7c did not afford optically active sulfinates 8a – c , but symmetrical sulfoxides 9a – c were obtained as products.…”

“…In the search for an alternative and new procedure for the preparation of diastereomeric sulfinates derived from readily available sugars, we focused our attention on diastereomerically pure ( R )-1,2- O -isopropylidene-3,5- O -sulfinyl-α- d -glucofuranose ( R )- 4 [ 28 ] ( Figure 1 ) and its reactivity with organometallic reagents.…”

“…The best results were obtained with diacetone α-D-glucose (DAG) and its cyclohexyl analogue, dicyclohexylidene α-D-glucose (DCG) (Scheme 2) [22][23][24][25][26][27]. In the search for an alternative and new procedure for the preparation of diastereomeric sulfinates derived from readily available sugars, we focused our attention on diastereomerically pure (R)-1,2-O-isopropylidene-3,5-O-sulfinyl-α-D-glucofuranose (R)-4 [28] (Figure 1) and its reactivity with organometallic reagents. The possibility of using this diastereoisomerically pure sulfite for the preparation of selected diastereoisomeric O-sulfinates results from our earlier observation that the reaction of prochiral sulfites with t-butylmagnesium chloride could be stopped on the stage of the corresponding sulfinic esters [29] and from the synthesis of enantiomerically enriched t-butanesulfinates 6 by the reaction of prochiral The possibility of using this diastereoisomerically pure sulfite for the preparation of selected diastereoisomeric O-sulfinates results from our earlier observation that the reaction of prochiral sulfites with t-butylmagnesium chloride could be stopped on the stage of the corresponding sulfinic esters [29] and from the synthesis of enantiomerically enriched t-butanesulfinates 6 by the reaction of prochiral sulfites 5 with t-butylmagnesium chloride carried out in the presence of optically active aminoalcohols as a chiral complexing agent (Scheme 3) [30].…”

Improved microbiological hydroxylation of sesquiterpenoids: semisynthesis, structural determination and biotransformation studies of cyclic sulfite eudesmane derivatives

“…23,26 In recent years, new synthetic applications of chiral cyclic sulfites as the intermediates in stereoselective transformations of diols have been developed. 27, 28 Their regioselective ring opening in nucleophilic substitution reactions with strong nucleophiles, their oxidation reaction to give cyclic sulfates as versatile intermediates in synthesis, or their applications in the…”