Synthesis of enantiomerically pure perhydrofuro[2,3-b]furans

Enantiomerically pure 2,5,6a-trisubstituted perhydrofuro[2,3-b]furans were obtained by the cyclization of bis-alkenylketones, promoted by camphorselenenyl sulfate produced in situ by oxidation of camphor diselenide with ammonium persulfate in a mixture of water and acetonitrile at room temperature. The cyclization reaction proceeded through a double selenohydroxylation of the two double bonds and produced a mixture of the two diastereoisomers trans- and cis-2,5-bis[(camphorseleno)methyl] perhydrofuro[2,3-b]furans. These were separated by medium pressure liquid chromatography and then deselenenylated with triphenyltin hydride and AIBN.

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(2S,5S)-2,5-Bis[(camphorseleno)methyl]-6a-phenylhexahydrofuro[2,3-b]furanC34H46O4Se2[α]D21=-2.7 (c 2.76, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5S

(2R,5R)-2,5-Bis[(camphorseleno)methyl]-6a-phenylhexahydrofuro[2,3-b]furanC34H46O4Se2[α]D24=+9.3 (c 2.65, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2R,5R

(2S,5R)-2,5-Bis[(camphorseleno)methyl]-6a-phenylhexahydrofuro[2,3-b]furanC34H46O4Se2[α]D19=-1.3 (c 3.74, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5R

(2R,5S)-2,5-Bis[(camphorseleno)methyl]-6a-phenylhexahydrofuro[2,3-b]furanC34H46O4Se2[α]D20=-27.8 (c 2.63, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2R,5S

(2S,5S)-2,5-Bis[(camphorseleno)methyl]-6a-methylhexahydrofuro[2,3-b]furanC29H44O4Se2[α]D17=+5.2 (c 3.83, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5S

(2R,5R)-2,5-Bis[(camphorseleno)methyl]-6a-methylhexahydrofuro[2,3-b]furanC29H44O4Se2[α]D19=+17.6 (c 3.35, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2R,5R

(2S,5R)-2,5-Bis[(camphorseleno)methyl]-6a-methylhexahydrofuro[2,3-b]furanC29H44O4Se2[α]D20=+9.1 (c 3.16, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5R

(2R,5R)-2,5-Dimethyl-6a-phenylhexahydrofuro[2,3-b]furanC14H18O2[α]D25=+29.6 (c 2.47, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2R,5R

(2S,5S)-2,5-Dimethyl-6a-phenylhexahydrofuro[2,3-b]furanC14H18O2[α]D25=-28.15 (c 1.91, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5S

(2R,5R)-2,5,6a-Trimethylhexahydrofuro[2,3-b]furanC9H16O2[α]D21=-21.7 (c 1.20, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2R,5R

(2S,5S)-2,5,6a-Trimethylhexahydrofuro[2,3-b]furanC9H16O2[α]D21=+21.7 (c 1.05, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: 2S,5S