Approach to a better understanding and modelling of β-pyrrolidinoalcohol ligands for enantioselective alkylation

Ultrasound‐mediated synthesis of camphoric acid‐based chiral salens for the enantioselective trimethylsilylcyanation of aldehydes

“…[1][2][3][4][5][6] Since Oguni's initial studies, 7-9 many tridentate and tetradentate Schiff bases have been used and found very efficient in the enantioselective trimethylsilylcyanation of aldehydes. [10][11][12][13][14][15][16] Extending our studies on enantioselective catalysis, [17][18][19] we undertook the synthesis of optically active salen ligands derived from (1R, 3S)-1,2,2-trimethyl-1,3-diaminocyclopentane, (1R, 3S)-1, a diamine which is readily obtained from natural camphoric acid, (1R, 3S)-1,2,2-trimethyl-1,3-cyclopentanedicarboxylic acid, (1R, 3S)-2. The structural characteristics of these salens seemed appropriate for their application in the enantioselective trimethylsilylcyanation of aromatic aldehydes.…”

Direct synthesis of functionalized 3-pyrrolidines and 4-piperidines using the borrowing hydrogen methodology

“…Switching from diols to triols such as the 1,2,4-butanetriol could allow the straightforward synthesis of 3-pyrrolidinol derivatives which are interesting scaffolds found in bioactive alkaloids 35 and used as intermediates for the synthesis of drugs such as Barnidipine. 36 The reported synthetic strategies often involved two steps either from malic acid, [37][38][39][40] cis-1,4-dichlorobutene, 35 N-substituted 3-pyrroline 41 or natural (-) vasicine. 42 Reaction of dimethylsulfoxonium methylide with epoxysulfonamides 43 as well as enzymatic hydroxylation of N-substituted pyrrolidines were also reported.…”

Glycerol-free biodiesel production through transesterification: a review

“…Glycerol carbonate was shown to be biodegradable, has a low toxicity and flammability and can be used as a bio-chemical precursor for the production of polycarbonates, polyurethanes, glycidol-based polymers and surfactants [26]. Citramalic acid is a chiral building block used for the synthesis of metal (ii) citramalates for application in material production as well as the production of chemical intermediates for synthesis of pharmaceutical products [27,28].…”