Keywords: Aldol reactions, Green chemistry, Homogeneous catalysis, Phase-transfer catalysis, Proline amides, Pyridinium salts.
Although, using new environmentally friendly reaction medium has found a lot of interest from the viewpoint of green chemistry, most of the organocatalytic aldol reactions performed in organic solvents such as DMSO, DMF, toluene, chloroform, and there is a few example on using water as solvent .
The synthesis of 1 started from an anti-selective asymmetric aldol reaction
(37) between silyl enol ether 2 and aldehyde 3 to set the two stereocenters at C4 and C5 of 4 (Fig.
They cover important natural products and pharmaceuticals, aldol reactions
, Michael reactions and conjugate additions, rearrangement reactions, cycloaddition reactions, asymmetric cross-coupling and Mizoroki-Heck reactions.
The construction utilized enantioselective aldol reactions as well as Stille and Wittig couplings to prepare the sensitive cyanotetraene part of the molecule.
Duthaler spoke about the use of cyclopentadienyltitanium-TADDOLS to mediate enantioselective additions of organolithium species to carbonyls and to effect aldol reactions as well as additions of allyl titanium species to carbonyls.
Logically organized by reaction type, the sections focus on [3,3]-sigmatropic rearrangements, aldol reactions
, metal allylation reactions, stereoselective reductions, and other reactions.
The topics include electrophilic aromatic substitution, organometallic reagents, acid halides and anhydrides, aldol reactions
, amines, and proton (1H) nuclear magnetic resonance.
Total Synthesis of Polyketides Using Asymmetric Aldol Reactions