Conformational Study of Poly(<i>N</i>-propargylamides) Having Bulky Pendant Groups
作者:Junichi Tabei、Ryoji Nomura、Toshio Masuda
DOI:10.1021/ma020320y
日期:2002.7.1
N-Propargylamides having chiral centers at the α-carbon of the amide groups, 1−3, were polymerized with (nbd)Rh+[η6-C6H5B-(C6H5)3] to afford polymers with moderate molecular weights (Mn = 6000−32 000) in good yield. The 1H NMR spectra demonstrated that the polymers have stereoregular structures (cis = 100%). The polymers were proven to take a helical conformation with an excess of one-handed screw
N-具有Propargylamides手性中心在酰胺基团的α碳,1 - 3,用聚合(NBD)的Rh + [ η 6 -C 6 H ^ 5乙-(C 6 H ^ 5)3 ],得到的聚合物用中等分子量(M n = 6000-32 000),收率良好。的1 1 H NMR谱表明,该聚合物具有立构规整结构(顺式= 100%)。事实证明,这些聚合物在CHCl 3中呈螺旋构型,并且带有多余的单手螺旋感。,其出色的CD效果和较大的旋光度得到了支持。已经证实,不仅通过空间排斥而且通过侧基之间的分子内氢键也使螺旋结构稳定。CD光谱研究表明,螺旋结构比在α位没有分支的聚合物更稳定,这使得聚合物在各种溶剂中以螺旋状态存在。聚合物的电子吸收,CD效应和旋光度与酰胺侧基之间的氢键程度密切相关。