Stereoselective total synthesis of dodoneine

The stereoselective total synthesis of the naturally occurring bioactive dihydropyranone dodoneine has been achieved involving the Sharpless asymmetric epoxidation, 1,3-syn diastereoselective reduction and Grubb’s ring-closing metathesis as key steps.

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((2S,3S)-3-(4-(Benzyloxy)phenethyl)oxiran-2-yl)methanolC18H20O3[α]D = −5.4 (c 0.5, CHCl3)Source of chirality: Sharpless epoxidationAbsolute configuration: (2S,3S)

(S)-5-(4-(Benzyloxy)phenyl)pentane-1,3-diolC18H22O3[α]D = −1.4 (c 0.5, CHCl3)Source of chirality: Sharpless epoxidationAbsolute configuration: (3S)

(S)-5-(4-(Benzyloxy)phenethyl)-2,2,3,3,9,9,10,10-octamethyl-4,8-dioxa-3,9-disilaundecaneC30H50O3Si2[α]D = +7.0 (c 0.5, CHCl3)Source of chirality: Sharpless epoxidationAbsolute configuration: (3S)

(S)-5-(4-(Benzyloxy)phenyl)-3-(tert-butyldimethylsilyloxy)pentan-1-olC24H36O3Si[α]D = −33.0 (c 0.6, CHCl3)Source of chirality: Sharpless epoxidationAbsolute configuration: (3S)

(S)-8-(4-(Benzyloxy)phenyl)-6-(tert-butyldimethylsilyloxy)oct-1-en-4-oneC27H38O3Si[α]D = +1.8 (c 0.6, CHCl3)Source of chirality: Sharpless epoxidationAbsolute configuration: (6S)

(4R,6S)-8-(4-(Benzyloxy)phenyl)-6-(tertbutyldimethylsilyloxy)oct-1-en-4-olC27H40O3Si[α]D = −0.1 (c 0.6, CHCl3)Source of chirality: Sharpless epoxidation and 1,3 inductionAbsolute configuration: (4R,6S)

(4R,6S)-8-(4-(Benzyloxy)phenyl)-6-(tertbutyldimethylsilyloxy)oct-1-en-4-ylacrylateC30H42O4Si[α]D = −2.0 (c 0.25, CHCl3)Source of Chirality: Sharpless epoxidation and 1,3 inductionAbsolute configuration: (4R,6S)

(4R,6S)-4-Allyl-6-(4-(benzyloxy)phenethyl)-2,2-dimethyl-1,3-dioxaneC24H30O3[α]D = −7.1 (c 0.15, CHCl3)Source of chirality: Sharpless epoxidation and 1,3 inductionAbsolute configuration: (3S,5R)

(R)-6-((S)-2-Hydroxy-4-(4-hydroxyphenyl)butyl)-5,6-dihydro-2H-pyran-2-oneC15H18O4[α]D = +39.3 (c 0.35, CHCl3)Source of chirality: Sharpless epoxidation and 1,3 inductionAbsolute configuration: (6R,2S)