Helicity induction on a poly(phenylacetylene) derivative bearing aza‐18‐crown‐6 ether pendants in water

A stereoregular poly(phenylacetylene) bearing the bulky aza‐18‐crown‐6 ether as the pendant (poly‐ 1 ) formed a predominantly one‐handed helical conformation upon complexation with various chiral compounds, such as amino acids, peptides, aminosugars, amines, and amino alcohols in water. The complexes exhibited an induced circular dichroism (ICD) in the UV–visible region of the polymer main chain. Therefore, poly‐ 1 can be used as a novel probe for determining the chirality of chiral compounds in water. The assay of 19 common free L ‐amino acids gave the same ICD sign at 0 °C except for L ‐phenylalanine. The effects of pH, temperature, guest concentration, and organic solvent content on the ICD during the complexation of poly‐ 1 with chiral compounds were also investigated. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1004–1013, 2003     

Chirality sensing of chiral pyrrolidines and piperazines with a liquid crystalline dynamic helical poly(phenylacetylene) bearing ethyl phosphonate pendant groups

Stereoregular cis‐transoidal poly(phenylacetylene) bearing a phosphonic acid monoethyl ester as the pendant group (poly‐ 1 ‐H) was found to form a preferred‐handed helix upon complexation with various optically active pyrrolidines and piperazines in dilute dimethyl sulfoxide and water, and the complexes exhibited characteristic induced circular dichroisms (ICDs) in the UV‐vis region of the polymer backbone. The Cotton effect signs in water reflect the absolute configuration of the pyrrolidines. The sodium salt of poly‐ 1 ‐H (poly‐ 1 ‐Na) and poly‐ 1 ‐H in the presence of optically active amines formed lyotropic nematic and cholesteric liquid crystalline phases in concentrated water solutions, respectively, indicating the rigid‐rod characteristic of the polymer main chain regardless of the lack of a single‐handed helix, as evidenced by the long persistence length of about 18 nm before and after the preferred‐handed helicity induction in the polymer. X‐ray diffraction of the oriented films of the nematic and cholesteric liquid crystalline polymers exhibited almost the same diffraction pattern, suggesting that both polymers have the same helical structure; dynamically racemic and one‐handed helices, respectively. On the basis of the X‐ray analysis, a possible helical structure of poly‐ 1 is proposed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1383–1390, 2010     

Poly(p‐benzamide) having isopropyl‐substituted chiral tri(ethylene glycol) side Chain: Synthesis and helical conformation

Isopropyl‐substituted tri(ethylene glycol) is used as a chiral side chain of N‐substituted poly(p‐benzamide) in order to increase the difference of stability between the right‐ and left‐handed helical structures of the polymer. The target polymer is synthesized by the chain‐growth condensation polymerization of the corresponding monomer with an initiator using lithium 1,1,1,3,3,3‐hexamethyldisilazide as a base. A circular dichroism (CD) study of the polymer reveals that the CD signal is due to an excess of a thermodynamically controlled right‐handed helical structure of the polymer, and that the replacement of the methyl group with a bulkier isopropyl group at the side chain of poly(p‐benzamide) increases the abundance of right‐handed helical structure in chloroform. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1623–1628     

Helix formation of poly(phenylacetylene) derivatives bearing amino groups at the meta position induced by optically active carboxylic acids

Two novel phenylacetylene derivatives bearing diethylaminomethyl groups at the meta position on phenyl groups [3‐(N,N‐diethylaminomethyl)phenyl]acetylene ( 1 ) and [3,5‐bis(N,N‐diethylaminomethyl)phenyl]acetylene ( 2 ) were synthesized and polymerized with [Rh(nbd)Cl]₂ (nbd: norbornadiene). Both monomers gave highly cis–transoidal stereoregular polymers that exhibited an induced circular dichroism (ICD) in the UV–visible region, probably because of a prevailing one‐handed helical conformation upon complexation with optically active carboxylic acids such as mandelic acid and lactic acid. The sign of the Cotton effects reflected the absolute configuration of the chiral acids. Therefore, these polymers can be used as a novel probe for determining the configuration of chiral acids. The polymers were stable in the presence of chiral acids in solution. The poly‐ 1 complexed with chiral acids exhibited a split‐type ICD, whereas the poly‐ 2 complexed with chiral acids showed a different, non‐split‐type ICD. The ICD pattern of the poly‐ 1 /chiral acids complexes dramatically changed with an increase in the concentration of the chiral acids, thus showing a non‐split‐type ICD similar to those of the poly‐ 2 /chiral acid complexes. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3180–3189, 2001     

Temperature‐Induced Chiroptical Changes in a Helical Poly(phenylacetylene) Bearing N,N‐Diisopropylaminomethyl Groups with Chiral Acids in Water

A stereoregular poly(phenylacetylene) bearing an N,N‐diisopropylaminomethyl group as the pendant (poly‐ 1 ) changed its structure into the prevailing one‐handed helical conformation upon complexation with optically active acids in water. The complexes exhibited induced circular dichroism (ICD) in the UV/Vis region of the polymer backbone. Poly‐ 1 is highly sensitive to the chirality of chiral acids and can detect a small enantiomeric imbalance in these acids, in particular, phenyl lactic acid in water. For example, a 0.005 % enantiomeric excess of phenyl lactic acid can be detected by CD spectroscopy. The observed ICD intensity and pattern of poly‐ 1 were dependent on the temperature and concentration of poly‐ 1 , probably due to aggregations of the polymer at high temperature as revealed by dynamic light scattering and AFM. On the basis of the temperature‐dependent ICD changes, the preferred chiral helical sense of poly‐ 1 was found to be controlled by noncovalent bonding interactions by using structurally different enantiomeric acids.     

Chiral discrimination of a helically organized crown ether array parallel to the helix axis of polyisocyanate

The asymmetric polymerization of 4′‐isocyanatobenzo‐18‐crown‐6 with the lithium amide of (S)‐(2‐methoxymethyl)pyrrolidine successfully proceeded to afford end‐functionalized poly(4′‐isocyanatobenzo‐18‐crown‐6) with (S)‐(2‐methoxymethyl)pyrrolidine (polymer 2 ). In the circular dichroism (CD) spectrum of 2 , a clear positive Cotton effect was observed in the range of 240–350 nm corresponding to the absorption of the polymer backbone, indicating that 2 partially formed a one‐handed helical structure, which was preserved by the chirality of (S)‐(2‐methoxymethyl)pyrrolidine bonding to the terminal end in 2 . In the titration experiments for the CD intensity of 2 in the presence of D ‐ and L ‐Phe·HClO₄ (where Phe is phenylalanine), a small but remarkable difference was observed in the amount of the chiral guest needed for saturation of the CD intensity and in the saturated CD intensity, indicating that the extremely stable, one‐handed helical part should exist in the main chain of 2 , which was not inverted even when the unfavorable chiral guest for the predominant helical sense, L ‐Phe·HClO₄, was added. In addition, helical polymer 2 exhibited a chiral discrimination ability toward racemic guests; that is, the guests were extracted from the aqueous phase into the organic phase with enantiomeric excess. The driving force of the chiral discrimination ability of 2 should certainly be attributed to the one‐handed helical structure in 2 . © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 325–334, 2006     

Unexpected Thermally Stable,Cholesteric Liquid‐Crystalline Helical Polyisocyanides with Memory of Macromolecular Helicity

The achiral sodium salt of poly(4‐carboxyphenyl isocyanide) (poly‐ 1 –Na) folds into a one‐handed helix induced by optically active amines in water. The induced helicity remains when the optically active amines are completely removed, and further modification of the side groups to amide residues is possible without loss of memory of macromolecular helicity. Although the helical poly‐ 1 –Na loses its chiral memory at high temperature, helical polyisocyanides modified with achiral primary amines, which no longer have any chiral components, keep their memory perfectly even at 100 °C in N,N‐dimethylformamide in some cases and exhibit cholesteric liquid‐crystalline phases, thus providing a robust scaffold with heat resistance to which a variety of functional groups can be introduced.     

Crystallization‐Driven Asymmetric Helical Assembly of Conjugated Block Copolymers and the Aggregation Induced White‐light Emission and Circularly Polarized Luminescence

Controlling the self‐assembly morphology of π‐conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3‐hexylthiophene)‐block‐poly(phenyl isocyanide)s (P3HT‐b‐PPI) copolymers composed of π‐conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization‐driven asymmetric self‐assembly (CDASA) of the block copolymers lead to the formation of single‐handed helical nanofibers with controlled length, narrow dispersity, and well‐defined helicity. During the self‐assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single‐handed helical assemblies of the block copolymers exhibited interesting white‐light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers.     

Helical poly(phenylacetylene) derived from L‐tyrosine: A promising candidate for functional helical polymers carrying transformable N‐ and C‐termini

A novel optically active phenylacetylene derivative, N‐(tert‐butoxycarbonyl)‐4‐ethynyl‐L ‐phenylalanine methyl ester ( 1 ), was synthesized from L ‐tyrosine and polymerized with a rhodium catalyst. The corresponding polymer [poly( 1 )] with a moderate molecular weight was obtained in a high yield. The alkaline hydrolysis of poly( 1 ) gave poly[N‐(tert‐butoxycarbonyl)‐4‐ethynyl‐L ‐phenylalanine] [poly( 2 )] carrying free carboxy groups. Polarimetric, CD, and UV–vis spectroscopy analyses revealed that poly( 1 ) took a predominantly one‐handed helical structure in MeOH and toluene, and poly( 2 ) took a helical structure in MeOH. The secondary structures of poly( 1 ) and poly( 2 ) could be tuned with heat and solvents. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1691–1698, 2007     

Helicity Induction and Memory of the Macromolecular Helicity in a Polyacetylene Bearing a Biphenyl Pendant

A novel, cis‐transoidal poly‐(phenylacetylene) bearing a carboxybiphenyl group as the pendant (poly‐ 1 ) was prepared by polymerization of (4′‐ethoxycarbonyl‐4‐biphenylyl)acetylene with a rhodium catalyst followed by hydrolysis of the ester groups. Upon complexation with various chiral amines and amino alcohols in dimethyl sulfoxide (DMSO), the polymer exhibited characteristic induced circular dichroism (ICD) in the UV/Vis region due to the predominantly one‐handed helix formation of the polymer backbone as well as an excess of a single‐handed, axially twisted conformation of the pendant biphenyl group. Poly‐ 1 complexed with (R)‐2‐amino‐1‐propanol showed unique time‐dependent inversion of the macromolecular helicity. Furthermore, the preferred‐handed helical conformation of poly‐ 1 induced by a chiral amine was further “memorized” after the chiral amine was replaced with achiral 2‐aminoethanol or n‐butylamine in DMSO. In sharp contrast to the previously reported memory in poly((4‐carboxyphenyl)acetylene), the present helicity memory of poly‐ 1 was accompanied by memory of the twisted biphenyl chirality in the pendants. Unprecedentedly, the helicity memory of poly‐ 1 with achiral 2‐aminoethanol was found to occur simultaneously with inversion of the axial chirality of the biphenyl groups followed by memory of the inverted biphenyl chirality, thus showing a significant change in the CD spectral pattern.     

Recyclable helical poly(phenylacetylene)‐supported catalyst for asymmetric aldol reaction in aqueous media

A novel one‐handed helical poly(phenylacetylene) bearing L‐hydroxyproline pendants (poly(PA‐P)) was synthesized as an eco‐friendly polymer‐supported catalyst for asymmetric reactions. The helical poly(PA‐P) catalyzed the asymmetric aldol reactions of cyclohexanone with p‐nitrobenzaldehyde, and showed good recyclability and higher enantiomeric excess (ee) in aqueous medias than that in organic medias. The one‐handed helicity of poly(PA‐P) was clearly affected by the water content in the aqueous media. The helical poly(PA‐P) showed the higher enantioselectivity (ee = 99%) than its monomer PA‐P (ee = 54%) in THF/H₂O (H₂O vol % = 25.0 vol %). After the one‐handed helical structure of poly(PA‐P) was destroyed by grinding treatment, the ee of the reaction clearly decreased from 99 to 49%. These indicate that the one‐handed helical structure of poly(PA‐P) played an important role in the high enantioselectivity of the asymmetric aldol reactions in the aqueous media. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1024–1031     

Helicity Induction and Its Static Memory of Poly(biphenylylacetylene)s Bearing Pyridine N‐Oxide Groups and Their Use as Asymmetric Organocatalysts

Novel poly(biphenylylacetylene) derivatives carrying different types of pyridine N‐oxide units with a bulky or less‐bulky substituent at a different position as the functional pendant groups (poly‐ 2a and poly‐ 2b ) were synthesized by the rhodium‐catalyzed polymerization of the corresponding monomers. The influence of the steric environment around the catalytically active pyridine N‐oxide sites on the helicity induction and its static memory as well as the asymmetric catalytic activities of the resulting helical polymers with a macromolecular helicity memory was investigated. The polyacetylenes formed an excess one‐handed helical conformation upon noncovalent interactions with optically active alcohols and the induced macromolecular helicities of the polyacetylenes were efficiently memorized after the removal of the chiral inducers. Poly‐ 2b with the macromolecular helicity memory showed an enantioselectivity for the catalytic asymmetric allylation of benzaldehydes, producing optically active allyl alcohols, although their enantioselectivities were low. On the other hand, poly‐ 2a exhibited a negligible catalytic activity probably due to the bulky substituent at the o‐position of the pyridine N‐oxide residues, while poly‐ 2a underwent a unique helix‐inversion with the increasing concentration of chiral alcohols and the opposite helicity of poly‐ 2a was further successfully memorized. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2481–2490     

Supramolecular Graft Copolymerization of a Polyester by Guest‐Selective Encapsulation of a Self‐Assembled Capsule

Repeating guest units of polyesters poly‐(R )‐ 2 were selectively encapsulated by capsule 1 (BF₄)₄ to produce supramolecular graft polymers. The encapsulation of the guest units was confirmed by ¹H NMR spectroscopy. The graft polymer structures were confirmed by the increase in the hydrodynamic radii and the solution viscosities of the polyesters upon complexation of the capsule. After the capsule was formed, atomic force microscopy showed extension of the polyester chains. The introduction of the graft chains onto poly‐(R )‐ 2 resulted in the main chain of the polymer having an M ‐helical morphology. The complexation of copolymers poly‐[(R )‐ 2 ‐co ‐(S )‐ 2 ] by the capsule gave rise to the unique chiral amplification known as the majority‐rules effect.     

Influence of stereoregularity and linkage groups on chiral recognition of poly(phenylacetylene) derivatives bearing L‐leucine ethyl ester pendants as chiral stationary phases for HPLC

Stereoregular poly(phenylacetylene) derivatives bearing L ‐leucine ethyl ester pendants, poly‐1 and poly‐2a , were, respectively, synthesized by the polymerization of N‐(4‐ethynylphenylcarbamoyl)‐L ‐leucine ethyl ester ( 1 ) and N‐(4‐ethynylphenyl‐carbonyl)‐L ‐leucine ethyl ester ( 2 ) using Rh(nbd)BPh₄ as a catalyst, while stereoirregular poly‐2b was synthesized by solid‐state thermal polymerization of 2 . Their chiral recognition abilities for nine racemates were evaluated as chiral stationary phases (CSPs) for high‐performance liquid chromatography (HPLC) after coating them on silica gel. Both poly‐1 and poly‐2a with a helical conformation showed their characteristic recognition depending on coating solvents and the linkage groups between poly(phenylacetylene) and L ‐leucine ethyl ester pendants. Poly‐2a with a shorter amide linkage showed higher chiral recognition than poly‐1 with a longer urea linkage. Coating solvents played an important role in the chiral recognition of both poly‐1 and poly‐2a due to the different conformation of the polymer main chains induced by the solvents. A few racemates were effectively resolved on the poly‐2a coated with a MeOH/CHCl₃ (3/7, v/v) mixture. The separation factors for these racemates were comparable to those obtained on the very popular CSPs derived from polysaccharide phenylcarbamates. Stereoirregular poly‐2b exhibited much lower chiral recognition than the corresponding stereoregular, helical poly‐2a , suggesting that the regular structure of poly(phenylacetylene) main chains is essential to attain high chiral recognition. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Two modes of asymmetric polymerization of phenylacetylenes having an L‐amino alcohol residue and two hydroxy groups

Four novel chiral phenylacetylenes having an L ‐amino alcohol residue and two hydroxymethyl groups were synthesized and polymerized by an achiral catalyst ((nbd)Rh⁺[η⁶‐(C₆H₅)B^?(C₆H₅)₃]) or a chiral catalytic system ([Rh(nbd)Cl]₂/(S)‐ or (R)‐phenylethylamine ((S)‐ or (R)‐PEA)). The two resulting polymers having an L ‐valinol or L ‐phenylalaninol residue showed Cotton effects at wavelengths around 430 nm. This observation indicated that they had an excess of one‐handed helical backbones. Positive and negative Cotton effects were observed only for the polymers having an L ‐valinol residue produced by using (R)‐ and (S)‐PEA as a cocatalyst, respectively, although the monomer had the same chirality. Even when the achiral catalyst was used, the two resulting polymers having an L ‐valinol or L ‐phenylalaninol residue showed Cotton effects despite the long distance between the chiral groups and the main chain. We have found the first example of a new type of chiral monomer, that is, a chiral phenylacetylene monomer having an L ‐amino alcohol residue and two hydroxy groups that was suitable for both modes of asymmetric polymerization, that is, the helix‐sense‐selective polymerization ( HSSP ) with the chiral catalytic system and the asymmetric‐induced polymerization ( AIP ) with the achiral catalyst. The other two monomers having L ‐alaninol and L ‐tyrosinol were found to be unsuitable to neither HSSP nor AIP because of their polymers' low solubility. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Synthesis and properties of optically active amino acid based polyacetylenes bearing eugenol and fluorene moieties

Novel optically active amino acid based polyacetylenes bearing eugenol and fluorene moieties were synthesized, and their properties, including chiroptical ones, were analyzed. N‐[1‐(3,4‐Dimethoxyphenyl)‐2‐propyloxycarbonyl]‐L ‐alanine N′‐propargylamide ( 1 ), N‐[1‐(3,4‐dimethoxyphenyl)‐2‐propyloxycarbonyl]‐L ‐alanine propargyl ester ( 2 ), N‐(9‐fluorenylmethoxycarbonyl)‐L ‐alanine N′‐propargylamide ( 3 ), and N‐(9‐fluorenylmethoxycarbonyl)‐L ‐alanine propargyl ester ( 4 ) were polymerized with a rhodium‐zwitterion catalyst in tetrahydrofuran to afford the corresponding polymers with moderate molecular weights ranging from 10,800 to 17,300 in good yields. Because of the large specific rotation and circular dichroism (CD) signal, it was concluded that the poly(N‐propargylamide)s [poly( 1 ) and poly( 3 )] took a helical structure with a predominantly one‐handed screw sense. The solvent and temperature could tune the helical structure of poly( 1 ). On the other hand, the poly(propargyl ester)s [poly( 2 ) and poly( 4 )] exhibited only small specific rotations and CD signals. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 810–819, 2006     

Synthesis of polyisocyanide derived from phenylalanine and its temperature‐dependent helical conformation

Screw‐sense‐selective polymerization of the chiral isocyanide monomers derived from phenylalanine with NiCl₂ as a catalyst in methanol to yield helical‐conjugated polyisocyanide was investigated with respect to the thermal stability of its helical conformation. Poly(1‐tert‐butoxycarbonyl‐2‐phenylethyl isocyanide) (poly 1c ) took a stable helical conformer independent of the polymerization temperature. In poly(1‐ethoxycarbonyl‐2‐phenylethyl isocyanide) (poly 2c ), which had slightly smaller side groups, the helical conformation was thermally destabilized. The specific rotation and circular dichroism of poly 2c prepared at temperatures greater than 40 °C were considerably depressed in comparison with the values for poly 2c prepared at or below room temperature. Additionally, poly 2c prepared at low temperatures exhibited reversible temperature‐dependent specific rotation and circular dichroism, whereas poly 1c showed few changes. It is suggested that polyisocyanide derived from phenylalanine takes various helical conformers (i.e., from tightly to loosely coiled helices), the thermal stability of which depends on the size of the side group. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 399–408, 2002     

Synthesis and chiral recognition of helical poly(phenylacetylene)s bearing l‐phenylglycinol and its phenylcarbamates as pendants

A series of novel stereoregular one‐handed helical poly(phenylacetylene) derivatives ( PPA‐1 and PPA‐1a～g ) bearing l ‐phenylglycinol and its phenylcarbamate residues as pendants was synthesized for use as chiral stationary phases (CSPs) for HPLC, and their chiral recognition abilities were evaluated using 13 racemates. The phenylcarbamate residues include an unsubstituted phenyl, three chloro‐substituted phenyls (3‐Cl, 4‐Cl, 3,5‐Cl₂), and three methyl‐substituted phenyls (3‐CH₃, 4‐CH₃, 3,5‐(CH₃)₂). The acidity of the phenylcarbamate N‐H proton and the hydrogen bonds formed between the N‐H groups of the phenylcarbamate residues were dependent on the type, position, and the number of substituents on the phenylcarbamate residues. The chiral recognition abilities of these polymers significantly depended on the dynamic helical conformation of the main chain with more or less regularly arranged pendants. The chiral recognition abilities seem to be improved by the introduction of substituents on the phenylcarbamate residues, and PPA‐1d bearing the more acidic N‐H groups due to the 3,5‐dichloro substituents, exhibited a higher chiral recognition than the others. PPA‐1d showed an efficient chiral recognition for some racemates, and baseline separation was possible for racemates 5 , 11 , 12 , and 15 . © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 809–821     

Multicolor single‐layer electroluminescence device using poly(L‐glutamate) for hole transport

Helical poly(L ‐glutamate) with carbazole (Cz) side chains (PCELG) was synthesized as a hole‐transport host material for a dye‐doped polymer electroluminescence (EL) device. The main‐ and side‐chain conformations were investigated by a combination of polarized infrared spectroscopy and semiempirical quantum chemical calculation. In an electrically poled PCELG crystalline film, the main chain was found to assume a right‐handed α‐helical conformation with an order parameter of ～0.8. The Cz plane at the terminal side chain is inclined by about 44° toward the helical axis, creating a regular stacked structure conforming to the rigid α‐helical backbone. The principal EL characteristics of these devices were determined and compared with those of devices made with poly(N‐vinyl carbazole) (PVCz). For green and blue light, EL devices using PCELG exhibited luminance efficiencies comparable to those using PVCz. To the best of our knowledge, this was the first demonstration of primary colors emitted by an organic EL device with a polypeptide hole‐transport host material. The experimental results suggested that the total concentration and spatial arrangement of the Cz groups play an important role in determining the EL characteristics of dye‐doped polymer EL devices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 496–502, 2010     

Helix‐sense‐selective copolymerization of triphenylmethyl methacrylate with chiral 2‐isopropenyl‐4‐phenyl‐2‐oxazoline

The asymmetric induction leading to a one‐handed helix was investigated in the anionic and radical copolymerization of triphenylmethyl methacrylate (TrMA) and (S)‐2‐isopropenyl‐4‐phenyl‐2‐oxazoline ((S)‐IPO), and highly isotactic copolymers with a reasonable optical activity were obtained. In the anionic copolymerization, the optical activity of the obtained copolymers depended on the polarity of solvents, and a highly optically active copolymer was produced in the copolymerization in toluene. The chiral oxazoline monomer functioned not only as a comonomer but also as a chiral ligand to endow the polymer with large negative optical rotation in the copolymerization with TrMA. The copolymers with small positive optical rotation were obtained in THF, indicating that IPO unit may work only as the chiral monomer that dictates the helical sense via copolymerization with TrMA. The isotacticity of the obtained copolymers depended on the contents of TrMA units in the copolymers, but was almost independent of the solvent for copolymerization. In the radical copolymerization, the obtained copolymers exhibited small optical activities. It seemed that the chiral monomer cannot induce one‐handed helical structure of TrMA sequences even if the sequences probably have a high isotacticity. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 441–447