A consecutive approach towards the stereoselective synthesis of trisubstituted THF domains

A highly efficient, consecutive approach for the construction of synthetically valued, enantiomerically pure, trisubstituted THF domains 3–10 in a stereoselective manner starting from glycal derived allylic alcohols 1a–1d under Sharpless asymmetric epoxidation (SAE) conditions is reported. The reaction involves the intramolecular asymmetric ring opening (ARO) of in situ formed enantiopure 2,3-epoxy alcohols followed by protection of the diol.

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(2S,3S,4S,5R)-1,2-O-Isopropylidine-3,6-anhydro-4-O-benzyl-d-galactitolC16H22O5De >99%[α]D = +14.0 (c 0.100, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S,4S,5R)

(2S,3S,4R,5R)-1,2-O-Isopropylidine-3,6-anhydro-4-O-benzyl-d-glucitolC16H22O5De >99%[α]D = −12.0 (c 0.100, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S,4R,5R)

(2S,3S,4S,5R)-1,2-O-Isopropylidine-3,6-anhydro-4,5-di-O-benzyl-d-galactitolC23H28O5De >99%[α]D = +5.95 (c 0.235, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S,4S,5R)

(2S,3S,4R,5R)-1,2-O-Isopropylidine-3,6-anhydro-4,5-di-O-benzyl-d-glucitolC23H28O5De >99%[α]D = −23.6 (c 0.165, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2S,3S,4R,5R)

(2R,3R,4S,5R)-1,2-O-Isopropylidine-3,6-anhydro-4-O-benzyl-d-galactitolC16H22O5De >99%[α]D = +47.3 (c 0.148, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3R,4S,5R)

(2R,3R,4R,5R)-1,2-O-Isopropylidine-3,6-anhydro-4-O-benzyl-d-glucitolC16H22O5De >99%[α]D = +4.95 (c 0.101, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3R,4R,5R)

(2R,3R,4S,5R)-1,2-O-Isopropylidine-3,6-anhydro-4,5-di-O-benzyl-d-galactitolC23H28O5De >99%[α]D = −7.7 (c 0.220, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3R,4S,5R)

(2R,3R,4R,5R)-1,2-O-Isopropylidine-3,6-anhydro-4,5-di-O-benzyl-d-glucitolC23H28O5De >99%[α]D = +14.0 (c 0.121, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3R,4R,5R)

(2R,3S)-4,5,6-Tri-O-benzyl-2,3-epoxy-d-glucitolC27H30O5De >99%[α]D = −6.5 (c 0.108, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (2R,3S,4R,5R)