Highly selective approach for the total synthesis of (+)-heliconol A

The total synthesis of heliconol A, a representative of a new class of polyketide-derived hemiketals containing a reduced furanocyclopentane unit, has been achieved via the stereoselective reduction of a ketone, the face selective dihydroxylation, a Sonogashira coupling reaction, and a cis-selective reduction as the key steps.

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(S)-2-Iodocyclopent-2-enolC5H7IO[α]D25=-25.5 (c 1.0, CHCl3)Absolute configuration: (S)

(S)-2-(Undec-1-ynyl)cyclopent-2-enolC16H26O[α]D25=-23.0 (c 1.4, CHCl3)Absolute configuration: (S)

(S)-tert-Butyldiphenyl(2-(undec-1-ynyl)cyclopent-2-enyloxy)silaneC32H44OSi[α]D25=-45.6 (c 1.9, CHCl3)Absolute configuration: (S)

(1S,2S,5S)-5-(tert-Butyldiphenylsilyloxy)-1-(undec-1-ynyl)-cyclopentane-1,2-diolC32H46O3Si[α]D25=-9.2 (c 1.5, CHCl3)Absolute configuration: (1S,2S,5S)

(2R,3S)-2-(tert-Butyldimethylsilyloxy)-3-(tert-butyldiphenylsilyloxy)-2-(undec-1-ynyl)cyclopentanoneC38H58O3Si2[α]D25=+6.6 (c 1.5, CHCl3)Absolute configuration: (2R,3S)

(2R,3S,Z)-2-(tert-Butyldimethylsilyloxy)-3-(tert-butyldiphenylsilyloxy)-2-(undec-1-enyl)cyclopentanoneC38H60O3Si2[α]D25=+2.4 (c 0.9, CHCl3)Absolute configuration: (2R,3S)

(+)-Heliconol AC16H30O5[α]D25=+19.6 (c 0.9, acetone)