2258-55-1Relevant academic research and scientific papers
Syn -selective vinylogous Kobayashi aldol reaction
Symkenberg, Gerrit,Kalesse, Markus
supporting information; experimental part, p. 1608 - 1611 (2012/05/07)
The Kobayashi aldol reaction has become a prominent transformation in polyketide syntheses. This methodology takes advantage of the directing effects of the Evans auxiliary and allows the stereoselective incorporation of a four carbon segment with two additional methyl branches establishing an anti-relationship between the two newly formed chiral centers. So far this transformation was restricted to anti-aldol products. We present here a modified protocol that provides the corresponding aldol product with high syn-selectivity.
DIENCARBONSAEUREN AUS 1,3-DIENEN UND CO2 DURCH C-C-VERKNUEPFUNG AN NICKEL(0)
Hoberg, H.,Schaefer, D.,Oster, B. W.
, p. 313 - 320 (2007/10/02)
(Lig)Ni0 systems react with 1,3-dienes in the presence of CO2 to give nickela carboxylates.The influence of ligands and temperature on the regioselectivity of the C-C bond formation is elucidated.In some cases the nickela carboxylates undergo reductive elimination under the influence of maleic anhydride, and the coupled diene/CO2 moiety rearranges to give the diene carboxylic acid.A possible reaction sequence is discussed.
