Marc Larchevêque

An alternative stereoselective synthesis of trans-(2R,3R)-3-hydroxypipecolic acid

Abstract The enantioselective synthesis of trans -(2 R ,3 R )-3-hydroxypipecolic acid 1b is presented, starting from O -protected methyl mandelate as chiral source. The synthesis involved a regioselective intramolecular nucleophilic substitution of an azido epoxide as the key step .

Stereocontrolled reductive amination of 3-hydroxy ketones

Abstract syn-1,3-Aminoalcohols are synthesized in high diastereomeric excess by reductive amination of 3-hydroxyketones with sodium cyanoborohydride in the presence of benzylamine.

An efficient synthesis of α- and β-aminophosphonic esters from α-amino acids

Abstract Catalytic hydrogenation of N -Boc aziridine 2-phosphonates derived from 3-amino-2-hydroxyphosphonates affords N -Boc α-aminophosphonic esters in high enantiomerical purities. Alternatively, the α-hydroxy β-aminophosphonic esters can be reduced into β-aminophosphonic esters by radical deoxygenation.

Reductive cyanation: A key step for a short synthesis of (−)-(2S,3S)-3-hydroxyproline

Abstract A short stereoselective synthesis of (−)-(2 S ,3 S )-3-hydroxyproline has been realized from L-malic acid as the source of chirality. The key step was the reductive cyanation of the intermediate 1a , in high stereoselectivity and yield.

A new route to (2S,4R)- and (2R,4S)-4-hydroxypipecolic acid

Abstract Both enantiomers of cis -4-hydroxypipecolic acid have been prepared by asymmetric synthesis using ( S )- or ( R )-glycidol as the chiral source, and involving a stereoselective hydrogenation of a six-membered cyclic imine. The latter is obtained by reduction and cyclization of a cyano β-hydroxy ketone.

A synthetic route to anti aminoalkyl epoxides by stereocontrolled reductive amination of ketoepoxides

anti-Aminoalkyl epoxides are synthesized in an enantiomerically pure form by stereoselective reductive amination of ketoepoxides derived from methyl glycidate with tetramethylammonium triacetoxyborohydride.

Synthesis of R-(−)-2-phenylpropanal: a potentially new route towards chiral 2-phenylalkanals

Abstract A facile two step synthesis of ( R )-2-phenylpropanal in high enantiomeric excess is described, starting from commercial ( S )-styrene oxide, involving as a key step a Dess–Martin oxidation.

A GENERAL STEREOCONTROLLED SYNTHESIS OF HYDROXYETHYLENE DIPEPTIDE ISOSTERES

Abstract Hydroxyethylene dipeptide isosteres were synthesized by stereocontrolled hydroboration of homoallylic alcohols derived from syn protected aminoepoxides followed by chemoselective oxidation of the resulting primary alcohols.

Asymmetric synthesis of the Abbott amino dihydroxyethylene dipeptide isostere subunit

Abstract The aminodiol 1b, a N-benzyl protected form of the Abbou dipeptide isostere 1a is prepared, starting from an appropriate α,β-unsaturated ester, involving an asymmetric dihydroxylation and a rearrangement of an intermediate anti α,β-aminoepoxide.

A general approach towards 2-substituted 3-hydroxy propanoates; application to the synthesis of methyl tropinate

Abstract Enantiomerically pure R of S 2-substituted 3-hydroxy propanoates may be prepared by regioselective BF 3 promoted opening of homochiral styrene oxide by lithium cyanocuprates followed by oxidative cleavage of the aromatic moiety with catalytic ruthenium trichloride.