%0 Journal Article
%T Enantioselective addition of diethylzinc to benzaldehyde catalyzed by an organometallic Ti(IV) compound and a xylose derivative
%A Parada
%A Jos¨¦
%A Herrera
%A Juan
%A Pedraza
%A A.
%J Journal of the Brazilian Chemical Society
%D 2009
%I Sociedade Brasileira de Qu¨ªmica, SBQ
%R 10.1590/S0103-50532009000100013
%X a derivative of d-xylose, 1,2-o-isopropylidene-¦Á-d-xylofuranose (1), with ti(oipr)4 was used as a chiral catalyst in the asymmetric alkylation of benzaldehyde with diethylzinc (et2zn) for the high-yield production (90% conversion) and moderate enantioselectivity (45% ee (s)) of 1-phenyl-1-propanol. optimum conditions (conversion and enantioselectivity) for the catalytic system formed by 1 and ti(iv) were 10.0 mol % of 1 and 1 equivalent of ti(iv) with respect to benzaldehyde in ch2cl2 as a solvent, at room temperature. in the asymmetric alkylation of benzaldehyde with et2zn compound 1 in substoichiometric amount with ti(oipr)4 forms a chiral catalyst of the ti(iv)-sugar type that ensures the good-yield conversion and the enantioselectivity of the reaction.
%K diethylzinc
%K xylose derivative
%K ti(iv)
%K titanium.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0103-50532009000100013&lng=en&nrm=iso&tlng=en