Synthetic polymers optically active compounds

PHTP is a chiral host which can be resolved into enantiomers DCA and ACA are (or derive from) naturally occurring optically active compounds. Using these hosts inclusion polymerization can be performed in a chiral environment and can be used for the synthesis of optically active polymers. This line of research has been very fruitful, both on the synthetic and on the theoretical plane. It has been ascertained that asymmetric inclusion polymerization occurs by a "through space" and not by a "through bond" induction only steric host-guest interactions (physical in nature) and not conventional chemical bonds are responsible for the transmission of chirality (W). 

The problems of charged and reactive polymers are correlated to optically active compounds and it shows an inherent property of both ordinary macromolecules as well as large range of synthetic polymers. Chiral compounds are optically active and essential for life such as proteins, polysaccharides, nucleic acids, etc. and chirality is most important for existence. About 97 % dmgs are formed from namral sources,... 

The optically active compounds are synthesized by highly efificient methodologies and catalysts. The various synthetic approaches for optically active polymers are described below ... 

More recently, in the 1980s and 1990s new series of fused phenothiazine derivatives, the benzo[a,b or c]phenothiazines (BPHTs), were synthesized [3, 21 and references therein] and have received a great deal of attention, mainly because of their potential applications and their important biomedical properties [12-24]. Indeed, some BPHTs are coloured compounds and have been applied as polycyclic dyes or pigments for synthetic polymers, and also in optical recording media ([21] and references therein). Moreover, certain benzo [a or c]phenothiazine derivatives are potential anti-helmintics, possess an antiviral activity, for example inhibiting the multiplication of encephalomyocarditis viruses in tissue cultures ([21,22], and refer-... 

We have been studying and developing the industrial-scale production of C3 and C4 chiral synthetic units such as 2,3-dichloro-l-propanol (DCP), epichlorohydrin (EP), 3-chloro-l,2-propanediol (CPD), glycidol (GLD), 4-chloro-3-hydroxy-butyrate (CHB), 3-hydroxy-y-butyrolactone (HL), etc. These compounds were not available even on a laboratory scale, although they have various possible applications for chiral pharmaceuticals, agrochemicals, optically active liquid crystals or polymers, etc. (Fig. 1) [1]. Our concept of a study and the development for the industrial production is shown in Fig. 2. 

From the discussion above, it appears that for synthetic optically active polymers with relatively high stereoregularity, probable preferential conformations should influence more or less the chiroptical properties. Usually, comparison with model compounds have been used to detect contributions of such ordered conformations according to the well-based assumption that, in their absence, chiroptical properties should mainly depend on monomeric unit behavior and, therefore, should be very similar to those of model molecules. This is correct only if actual ordered conformation effects prevail i.e. if no other phenomena can give similar optical activity changes. 

In this chapter chiral thermotropic semisynthetic and synthetic polymers are included. They will be treated in separate sections focused on cellulose and polypeptide systems and on polyesters containing (-h)-(/ )-3-methyl-adipic acid as the chiral moiety. Mixtures of achiral condensation polymers with optically active low molar mass compounds will be also briefly discussed. 

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