Optically active cyclophanes, such as helical molecules and three-dimensional, cagelike cyclophanes have been the subject of extensive investigation from the standpoints of structural chemistry and material science.

Effects of the composition of chiral-achiral N-propargylamide copolymers on their secondary structures and optical activity

The electronic and steric effects of substituted groups,the structures of chiral catalysts and chiral reagents and the reaction system on optical activity of products are summarized.

Thus,four kinds of hydantoins,(5R) 5 (5 imidazolylmethyl) 3 phenyl 2,4 imidazolidinedione,(5R) 5 benzyl 3 phenyl 2,4 imidazolidinedione,(5S) 5 methyl 3 phenyl 2,4 imidazolidinedione and (5S) 5 hydroxymethyl 3 phenyl 2,4 imidazolidinedione,were prepared,which all have certain optical activity and were proved to have the expected structures by elementary analysis,IR and .

This article reviews the preparation of optically active cyanohydrins, which are formed by prochiral suitable substrates catalyzed by optically active biological or chemical catalysts.

In this paper, the brominations of activated arenes a.

Study on the effect of Fe(Ⅲ) on the photochemical activity of nanometer TiO_2;

Opinions were put forward that impaired the aging behavior of the basis material was not the photocatalytic effect but the photochemical activity from lattice defect of TiO_2.

Nona-TiO 2 doped with Mo was prepared in to approaches in an effort to block out its photochemical activity,lower its photosensitivity and improve its weather durabikity.