69370-45-2Relevant academic research and scientific papers
Additions of Carboxylic Acid Dianions to α,β-Unsaturated Carbonyl Compounds - Control of the 1,2-/1,4-Regioselectivity by Steric Substituent Effects
Mulzer, Johann,Bruentrup, Gisela,Hartz, Georg,Kuehl, Uwe,Blaschek, Ursula,Boehrer, Gerald
, p. 3701 - 3724 (2007/10/02)
Dilithium carboxylic acid dianions 1 attack α,β-unsaturated aldehydes (2) 1,2-regiospecifically with formation of the unsaturated β-hydroxy carboxylic acids 3/4.Additionally, the addition of the phenylacetate dianion 1a can be conducted to the threo-isomer with high selectivity by reversible reaction. - α,β-Enones (8) add 1 irreversibly in 1,2- and 1,4-position.Depending on the substitution pattern, the whole range from pure 1,2- to pure 1,4-adduct is covered.The influence of the 1-counterion M and of the solvent is significant; the 1,4-portion increases with the complexing effect of M and with the Lewis-basicity of the solvent.
