This paper describes the investigation of an interaction between chiral induction behavior and a chiral polymer obtained by cyclopolymerization of a bisacrylamide (1) prepared from a-pinene and acrylonitrile. Poly(1) can interact with aromatic aldehydes, as confirmed by infrared (IR), circular dichroism (CD), diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY) and 1-D nuclear Overhauser effect difference (1-D NOE) measurements. The observed induced CD demonstrates that the chiral framework of poly(1) forced aldehydes to remain in chiral environments. IR, DOSY and 1-D NOE measurements on mixtures of poly (1) Keywords: chiral interaction; cyclopolymerization; radical polymerization INTRODUCTION Chiral polymers have been used as stationary phases for chiral separation 1-10 and as templates for asymmetric reactions. 11-15 To achieve high performance with a chiral polymer, the polymer needs appropriate functional groups and a rigid structure. As a candidate, we designed a chiral polyacrylamide prepared through cyclopolymerization of a chiral bisacrylamide (1) (Scheme 1). 16 The monomer can easily be prepared by a one-step reaction of a-pinene and acrylonitrile. 17 The cyclopolymerization proceeds through the formation of 10-or 11-membered chiral rings. Although the structure of the rings has not been clarified completely by spectroscopic analyses, computational calculation suggested that the 11-membered ring formations are significantly predominant over 10-membered ring formations because of steric hindrance and the stability of propagating radicals. The details will be described elsewhere. In spite of the typically unfavorable large ring formation, this cyclopolymerization can yield soluble polymers bearing the desired cyclic units in quantitative yields. The selectivity of the cyclopolymerization without branching was confirmed by matrix-assisted laser desorption-ionization time of flight mass spectroscopy analysis of poly(1) obtained by reversible additionfragmentation chain transfer (RAFT) polymerization, indicating that poly(1) has only one initiating and terminating group originating from the chain transfer agent. The circular dichroism (CD) spectra of the resulting polymers show Cotton effects originating from the amide moieties in chiral environments and suggest the potential application of poly(1) as a chiral polymer. The chiral rings in poly(1) contain
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