Chemistry of sulfones: synthesis of a new chiral nucleophilic catalyst

A chiral pyrrolidinopyridine was synthesized by using Buchwald methodology. The sulfone was used to add a benzyl group, which positioned a phenyl near the reacting position.

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(2S,3S)-2,3-Bis(benzyloxy)-1,4-bis[[(4-methyl-phenyl)sulfonyl]oxy]butaneC32H34O8S2Ee, de >95% (NMR)[α]D20=+14.6 (c 0.3, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,3S

(2S,3S)-2,3-Bis(benzyloxy)-1,4-bis(methylsulfonyloxy)butaneC20H26O8S2Ee, de >95% (NMR)[α]D20=+17.9 (c 0.5, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,3S

(3′S,4′S)-4-[(3′,4′)-Bis(benzyloxy)pyrrolidin-1′-yl]pyridineC23H24N2O2Ee, de >95% (NMR)[α]D20=+8.9 (c 1.2, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 3′S,4′S

(2S,3S,4R)-2-Benzenesulfonylmethyl-3,4-isopropylidenedioxypyrrolidineC14H19NO4SEe, de >95% (NMR)[α]D20=-26.0 (c 0.1, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,3S,4R

(2′S,3′S,4′R)-4-(2′-Benzenesulfonylmethyl-3′,4′-isopropylidenedioxypyrrolidin-1′-yl)pyridineC19H22N2O4SEe, de >95% (NMR)[α]D20=-13.6 (c 0.8, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2′S,3′S,4′R

(2′R,3′S,4′R,1″R)-4-[2′-(1″-Benzenesulfonyl-2″-phenylethyl)-3′,4′-isopropylidenedioxypyrrolidin-1′-yl]N-benzylpyridinium bromideC33H35BrN2O4SEe, de >95% (NMR)[α]D20=-22.2 (c 0.6, MeOH)Source of chirality: asymmetric synthesisAbsolute configuration: 2′R,3′S,4′R,1″R

(2′R,3′S,4′R,1″R)-4-[2′-(1′-Benzenesulfonyl-2″-phenylethyl)-3′,4′-isopropylidenedioxypyrrolidin-1-yl]pyridineC26H28N2O4SEe, de >95% (NMR)[α]D20=-28.3 (c 0.9, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2′R,3′S,4′R,1″R