138513-51-6Relevant articles and documents
Chemoenzymatic Preparation of Asymmetrized Tris(hydroxymethyl)methane (THYM*) and of Asymmetrized Bis(hydroxymethyl)acetaldehyde (BHYMA*) as New Highly Versatile Chiral Building Blocks
Guanti, Giuseppe,Banfi, Luca,Narisano, Enrica
, p. 1540 - 1554 (2007/10/02)
A series of asymmetrized tris(hydroxymethyl)methanes 2 and bis(hydroxymethyl)acetaldehydes 3 have been prepared in both enantiomeric forms through a chemoenzymatic methodology.The key step is the highly enantioselective PPL-catalyzed monohydrolysis of 2(E)-alkenyl-1,3-diacetoxypropanes 25-27.A careful study on the effect of unsaturations adjacent to the prochiral center in a series of 2-substituted 1,3-diacetoxypropanes has confirmed the suggested beneficial effect of a ? system in that position but has also unveiled an unprecedented dramatic effect of double-bond configuration on enantioselectivity.A new empirical model for the interpretation of these and other results, based both on polarity and steric arguments, is proposed.This study provides a general protocol for the efficient synthesis of asymmetrized 1,3-propanediols bearing in position 2 saturated or unsaturated carbon chains.
SYNTHESIS OF BOTH ENANTIOMERIC FORMS OF 2-SUBSTITUTED 1,3-PROPANEDIOL MONOACETATES STARTING FROM A COMMON PROCHIRAL PRECURSOR, USING ENZYMATIC TRANSFORMATIONS IN AQUEOUS AND IN ORGANIC MEDIA
Tombo, G. M. Ramos,Schaer, H.-P.,Busquets Fernandez I,Ghisalba, O.
, p. 5707 - 5710 (2007/10/02)
A direct entry to both enantiomeric forms c and ent-c based on enzyme catalyzed transformations of prochiral compounds of type a and b is described.The catalysts used are carboxyl esterase preparations obtained from crude porcine pancreas lipase.
