Unusual Stereochemical Opportunities in Extended Helical Conformations

化学部的有机动力学项目和材料研究部的聚合物项目的资助支持了理工大学绿色教授和Levon博士的持续工作。这一研究结果将对聚合物的右旋或左手螺旋性质提供新的认识和见解。控制右旋或左旋螺旋优先形成的因素将被探讨。由于生物聚合物，如肽和DNA，可以存在于右手或左手螺旋，这项工作是特别感兴趣的。绿色和莱文博士将提供新的和重要的信息在三个领域，其中所有有关的单体的手性如何影响的螺旋手性的聚合物。在第一个方面，将研究手性中心对异氰酸酯聚合物的手性螺旋度的影响。研究发现，在R-1-氘代己基异氰酸酯中，氘取代形成的手性中心对多异氰酸酯的螺旋手性有很大的影响。这一观察结果将进一步研究，以及从R-2-deuteriohexylisocyanate产生的聚合物的螺旋手性。在第二个领域中，将研究N-羧基酸酐单体中含有联苯基的侧链的螺旋扭曲与聚谷氨酸酯聚合物的螺旋度之间的关系。在第三个方面，将研究作为功能的单体的立体化学的聚异氰酸酯的凝胶化。

This grant from the Organic Dynamics Program of the Chemistry Division and the Polymers Program of the Division of Materials Research supports the continuing work of Professor Green and Dr. Levon at the Polytechnic University. The results of this research will give new understanding and insight to the right or left hand helical nature of polymers. The factors that control the preferential formation of right- or left- handed helices will be explored. Since bio-polymers, such as peptides and DNA, can exist in right- or left- handed helices, this work is of particular interest. Drs. Green and Levon will provide new and important information in three areas, of which all are related to how the chirality of the monomers effect the helical chirality of the polymers. In the first area, the effect of a chiral center on the chiral helicity of isocyanate polymers will be studied. It has been found that a chiral center by virtue of deuterium substitution in R-1- deuteriohexylisocyanate had a profound effect on the helical chirality of the polyisocyanate. This observation will be studied further as well as the helical chirality of the polymer resulting from R-2-deuteriohexylisocyanate. In the second area, a study will be made of the relationship between helical twist of a side chain containing a biphenyl group in an N-carboxyanhydride monomer and helicity of the polyglutamate polymer. In the third area, the gelation of polyisocyanides as function of the stereochemistry of the monomer will be investigated.