95891-76-2Relevant academic research and scientific papers
Diethylaluminum ethoxide mediated crossed aldol reaction of enol esters with carbonyl compounds
Mukaiyama, Teruaki,Shibata, Jun,Shimamura, Tadashi,Shiina, Isamu
, p. 951 - 952 (1999)
Crossed aldol reaction of enol esters, stable carbon nucleophiles, with carbonyl compounds is effectively performed by the promotion of diethylaluminum ethoxide under mild conditions. This reaction is applicable not only to simple enol esters but also to
Nickel- and Palladium-Catalyzed Aldol-Type Condensation by Enol Esters
Masuyama, Yoshiro,Sakai, Tatsuya,Kato, Takeshi,Kurusu, Yasuhiko
, p. 2265 - 2272 (2007/10/02)
PdCl2(PhCN)2-SnCl2, bis(1,5-cyclooctadiene)nickel(0) /PPh3-Zn, NiBr2(PPh3)2-Zn, or Pd-(OAc)2/PPh3-Zn catalytic systems induced aldol-type condensation of isopropenyl acetate with aldehydes to produce 4-substituted (E)-3-buten-2-ones.PdCl2(PhCN)2-SnCl2 was utilized in the aldol-type reaction with any arenecarbaldehyde, bearing either an electron-donating group or an electron-withdrawing group, at 50 deg C in acetonitrile.Catalytic systems using zinc, in particular Ni(cod)2/PPh3-Zn, exhibited some high chemoselectivities at 60 deg C in dioxane: (1) an aldehyde only reacted in the presence of an internal ester or ketone, (2) olefinic aldehydes only reacted in the presence of saturated aliphatic aldehydes, (3) reactivity in the condensation with substituted benzaldehydes is the inverse of that in usual nucleophilic addition to carbonyl compound, and (4) 2-methoxybenzaldehyde only reacted in the presence of 4-methoxybenzaldehyde.Using PdCl2(PhCN)2-SnCl2, Ni(cod)2/PPh3-Zn, or Pd(OAc)2/PPh3-Zn, cyclic enol ester, namely 5-methyl-2(3H)-furanone also caused aldol-type reaction with carbonyl compounds.The reaction with Ni(cod)2/PPh3-Zn or Pd(OAc)2/PPh3-Zn at 60 deg C in dioxane selectively produced 5-substituted 4-acetyl-2(5H)-furanones via dehydrogenation of γ-substituted β-acetyl-γ-butyrolactones.
Aldol-Type Reaction by Propen-2-yl Acetate with NCS/SnCl2/ROH
Masuyama, Yoshiro,Kobayashi, Yumiko,Yanagi, Ryota,Kurusu, Yasuhiko
, p. 2039 - 2042 (2007/10/02)
The addition of N-chlorosuccinimide (NCS) to a solution of propen-2-yl acetate, aldehydes, SnCl2, and benzyl alcohol in CH2Cl2 or CH3CN caused an aldol-type reaction to produce 4-substituted 4-benzyloxybutan-2-ones in high yields.Use of methanol instead of benzyl alcohol produced not only 4-methoxybutan-2-one but also 3-buten-2-one by dehydromethoxylation.
Palladium-catalyzed aldol-type condensation by enol esters with SnCl2
Masuyama, Yoshiro,Sakai, Tatsuya,Kurusu, Yasuhiko
, p. 653 - 656 (2007/10/02)
Using PdCl2(PhCN)2-SnCl2, enol esters caused aldol-type condensation with aldehydes at 50°C in acetonitrile to produce (E)-α,β-unsaturated carbonyl compounds. Cyclic enol ester such as α-angelicalactone also reacted with aldehydes under the same conditions to afford γ-substituted β-acetyle-γ-butyrolactones and/or 5-substituted 4-acetyl-2(5H)-furanones.
