Catalytic asymmetric synthesis of α-methylene-β-hydroxy-ketones
作者:Anthony G. M. Barrett、Akio Kamimura
DOI:10.1039/c39950001755
日期:——
Condensation of an α,β-unsaturated ketone, an aldehyde and trimethylsilyl phenyl sulfide or selenide, catalysed by a chiral (acyioxy)borane, and subsequent oxidative elimination gives the title adducts in high enantiomeric excess.
Stereoselective Synthesis of Methyl 7-Dihydro-trioxacarcinoside B
作者:Christian M. König、Klaus Harms、Ulrich Koert
DOI:10.1021/ol702078t
日期:2007.11.1
A stereoselective synthesis of 7-dihydro-triocacarcinose B, a branched octose from the quinocyclines, has been achieved. The biocatalytic resolution of a Baylis-Hillman adduct and a subsequent ring-closing metathesis were used to assemble the molecular framework. Subsequent key steps were a highly stereoselective epoxidation and a regio- and stereoselective opening of the epoxide by allyl alcohol and