25462-27-5Relevant academic research and scientific papers
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.
Thiol esters in organic synthesis XVII. S,S'-diethyl dithiomalonate as masked ethanol carbanion and 1,3-diol equivalent in the Knoevenagel condensation
Rose,Liu
, p. 2089 - 2095 (2007/10/02)
S,S'-Diethyl dithiomalonate (1) has been shown to be a useful reagent in the Knoevenagel condensation with aldehydes, using DABCO as the base. The resultant products can be reduced either to 1,3-diols by use of sodium borohydride or to ethanol derivatives using Raney Nickel.
