Experimental and theoretical investigation of the enantioselectivehydrogenation of ethyl pyruvate with a Pt catalyst with newnon-cinchona chiral modifiers

JOSÉ F. RUGGERA; ANDREA. B. MERLO; REINALDO PIS DIEZ; MÓNICA L. CASELLA

JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 423 p. 233 - 239

1381-1169

The enantioselective hydrogenation of ethyl pyruvate using a Pt/SiO2catalyst modified with sixdifferent chiral modifiers was studied. The chiral modifiers chosen were: (S)-(+)-1-aminoindan,(R)-(−)-1-aminoindan, (1R,2S)-(+)-cis-1- amino-2-indanol, (1S,2R)-(−)-cis-1-amino-2-indanol, (S)-(+)-1-indanol and (R)-(−)-1-indanol.An excess of the (R) enantiomer of the product of 63% and 45% with(S)-(+)-1-aminoindan and (R)-(−)-1-aminoindan modifiers, respectively was obtained. When using(1S,2R)-(−)-cis-1-amino-2-indanol and (1R,2S)-(+)-cis-1-amino-2-indanol, the enantiomeric excess (ee%)obtained was 30% and 5%, respectively, while with both indanols ee% did not exceed 8%. Molecularmodeling of the complex formed between the chiral modifier and ethyl pyruvate performed by DFTcalculations allowed predicting the values of ee% obtained experimentally. The low ee% value obtainedboth aminoindanol chiral modifiers were used, could be explained by the analysis of non-covalent inter-actions (NCI) method. These calculations demonstrated the presence of an intramolecular hydrogen bondin the structure of these modifiers.