Maurice Le Corre

Phosphine-borane complexes; direct use in asymmetric catalysis

Abstract An easy and soft method of decomplexation of phosphine-borane complexes, by DABCO, allows its use in situ in asymmetric catalytic hydrogenation of double bonds with metal phosphine complexes.

Activation of phosphines with borane

Abstract Phosphine-borane complexes are very stable reagents. When borane is added to the phosphene, these complexes have a reactivity similar to phosphine-oxide. Alkylation reactions and olefination reactions (Horner type 1 ) with these complexes are easily obtained.

Expedient synthesis of (−)-(1S, 2R)-Allonorcoronamic acid

Abstract The title amino acid was synthesized in enantiomerically pure form, starting from ( S )-(+)-1,2-propanediol 2 in three steps, by condensation of cyclic sulfate 3 with methyl benzylideneglycinate.

Asymmetric synthesis of a phosphonic analogue of (−)-allo-norcoronamic acid

Abstract (−)-(1R,2R)-1-Amino-2-methylcyclopropanephosphonic acid was synthesized in an enantiomerically pure form starting from the cyclic sulfate of (+)-(S)-1,2-propanediol and dimethyl t-butoxycarbonylmethylphosphonate.

Stereoselective synthesis of new functionalized bisphosphines

Abstract Chiral functionalized bisdiphenylphosphines have been prepared and isolated from natural tartaric acid via the dihydrophosphorylation of dimethyl 4,5-O-isopropylidene-2,6-octanedienedioate, 4,5-O-isopropylidene-2,6-octanedienedinitrile and bis 5 (H)-2-furanone.

First asymmetric synthesis of (−)-(2S, 3R)-methanoproline

Abstract The title amino acid was synthesized in enantiomerically pure form, starting from ( S )-(−)-butanetriol 1 , by condensation of cyclic sulfate 3 with methyl benzylideneglycinate.

Synthesis of optically active 2,3-methanopipecolic acid

Abstract The title compound was synthesized in enantiomerically pure form, starting from L -glutamic acid.

Bithiocamphor: an interesting synthon for the synthesis of chiral ligands

Abstract Bithiocamphor 1 was studied; its reduction led to dithiols 3a and 3b , its oxidation led to bicamphor 8 .

Efficient synthesis of 3-methylene-2-pyrrolidinone and highly exoselective Diels-Alder addition to cyclopentadiene

Abstract A new efficient synthesis of 3-methylene 2-pyrrolidinone 1 ylide-lactame 6 is reported. Diels-Alder cycloadditions of 1 to cyclopentadiene exhibited very high exoselectivities, regardless of the experimental conditions. These results confirm the generality of exoselectivity for conformationally restricted s-cis dienophiles and indicate that the dienophile functionality and dipole moment have little influence on its magnitude.

Enantiospecific synthesis of norcoronamic acids

Abstract The synthesis of enantiomerically pure norcoronamic acids, starting from enantiomerically pure 1,2-propanediols, is described.