853193-61-0Relevant articles and documents
Solid-phase synthesis of [5.5]-spiroketals
Sommer, Stefan,Kuehn, Marc,Waldmann, Herbert
supporting information; experimental part, p. 1736 - 1750 (2009/08/14)
An efficient and reliable multi-step synthesis of 251 natural product-like [5.5]-spiroketals on solid supports has been developed. As central key step, a double intramolecular hetero-Michael (DIHMA) reaction to alkynones was applied. The sequence allows for introduction of numerous substituents on the scaffold and for variation of stereochemistry. [5.5]-Spiroketals bearing an additional ketone were obtained in high overall yields. Further diversification was achieved by reduction of the ketone and reductive amination using polymer-supported borohydride, Grignard reaction and conversion to oxime derivatives in the solution phase.
Remote asymmetric induction in an intramolecular ionic Diels-Alder reaction: Application to the total synthesis of (+)-dihydrocompactin
Sammakia, Tarek,Johns, Deidre M.,Kim, Ganghyeok,Berliner, Martin A.
, p. 6504 - 6505 (2007/10/03)
The total synthesis of (+)-dihydrocompactin via an intramolecular ionic Diels-Alder reaction that proceeds with remote stereocontrol is described. This reaction proceeds by an intermediate vinyl-oxocarbenium ion (6), the conformational constraints of whic