An enantiodivergent synthesis of both (+)- and (−)-disparlure from (R)-2,3-cyclohexylideneglyceraldehyde

Reduction of ketone 3 derived from (R)-2,3-cyclohexylideneglyceraldehyde 1 with some common hydrides took place with syn-selectivity. The resulting major product 4a has been exploited as a common chiral template to prepare both enantiomers Ia,b of disparlure.

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(2R,3R)-1,2-O-Cyclohexylidene-3-O-(tert)-butyldiphenylsilyltridecane-1,2,3-triolC35H54O3Si[α]D25=+3.75 (c 0.7, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(2R,3R)-3-O-(tert)-Butyldiphenylsilyltridecane-1,2,3-triolC29H46O3Si[α]D25=-20.15 (c 0.8, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(2R,3R)-1,2-Epoxy-3-(tert)-butyldiphenylsilyloxytridecaneC29H44O2Si[α]D25=-16.8 (c 0.9, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(7R,8R)-2-Methyl-8-O-(tert)-butyldiphenylsilyl-7,8-octadecanediolC35H58O2Si[α]D25=+4.7 (c 1.07, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (7R,8R)

(2R,3R)-1,2-O-Cyclohexylidene-3-O-benzyltridecane-1,2,3-triolC26H42O3[α]D25=+16.9 (c 1.5, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(2R,3R)-3-O-Benzyltridecane-1,2,3-triolC20H34O3[α]D22=+4.5 (c 2.01, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(2R,3R)-1,2-Epoxy-3-benzyloxytridecaneC20H32O2[α]D25=+16.7 (c 1.08, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (2R,3R)

(7R,8R)-2-Methyl-8-O-benzyl-7,8-octadecanediolC26H46O2[α]D25=+10.3 (c 0.7, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (7R,8R)

(7R,8R)-2-Methyl-7-O-(tert)-butyldimethylsilyl-7,8-octadecanediolC25H54O2Si[α]D25=-4.2 (c 0.7, CHCl3)Source of chirality: (R)-2,3-cyclohexylideneglyceraldehydeAbsolute configuration: (7R,8R)