It is believed that effective stereochemical communication between substrate and enzyme is essen-tial for attaining high enantioselectivity in asymmetric reaction, and most of the successful salen-M catalysts also operate on this principle.

The different selectivities,including chemoselectivity,regioselectivity,syn/trans selectivity,diastereoselectivity,and enantioselectivity,of organic reactions under the microwave-assisted and conventional heating conditions are reviewed.

Epoxidation of 4-acetamidocyclopentene furnished good diastereoselectivity comparable to that of allylic ones.

Three strategies (additive, chiral auxiliary or chiral reagent) were developed to improve the diastereoselectivity or enantioselectivity of the ylide cyclopropanation reactions.

Highly Diastereoselective Epoxidation of △～5-Steroids Derivatives Catalyzed by Polymer-Supported Metalloporphyrins;

Our calculations confirm that title reaction consists of two parallel step processes, in which complexes, TS, intermediates and enantiomer middle products are located on the enantioselective reaction pathway between oxazaphospholidine borane adduct and acetophenone.

The enantioselective Diels-Alder reaction of N-propenoyl-1,3-oxazolidin-2-one with cyclopentadiene was catalyzed by free and polymer-supported complexes of titanium with N-sulfonyl-L-amino acids.