The amplified circularly polarized luminescence emission response of chiral 1,1′‐binaphthol‐based polymers via Zn(II)‐coordination fluorescence enhancement

Two kinds of chiral 1,1′‐binaphthol (BINOL)‐based polymer enantiomers were designed and synthesized by the polymerization of 5,5′‐((2,2′‐bis (octyloxy)‐[1,1′‐binaphthalene]‐3,3′‐diyl)bis(ethyne‐2,1‐diyl))bis(2‐hydroxybenzaldehyde) ( M1 ) with alkyl diamine ( M2 ) via nucleophilic addition–elimination reaction. The resulting chiral polymers can exhibit mirror image cotton effects either in the absence or in the presence of Zn²⁺ ion. Almost no fluorescence or circularly polarized luminescence (CPL) emission could be observed for two chiral BINOL‐based polymer enantiomers in the absence of Zn²⁺. Interestingly, the chiral polymers can show strong fluorescence and CPL response signals upon the addition of Zn²⁺, which can be attributed to Zn²⁺‐coordination fluorescence enhancement effect. This work can develop a new strategy on the design of the novel CPL materials via metal‐coordination reaction. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1282–1288     

Asymmetric Hydroformylation of 4‐Vinyl‐1,3‐dioxolan‐2‐one

A chiral cyclic carbonate, 4‐vinyl‐1,3‐dioxolan‐2‐one was used as racemic substrate in asymmetric hydroformylation. The catalysts were formed in situ from “pre‐formed” PtCl₂(diphosphine) and tin(II) chloride. (2S,4S )‐2,4‐Bis(diphenylphosphinopentane ((S,S )‐BDPP)), (S,S )‐2,3‐O‐izopropylidine‐2,3‐dihydroxy‐1,4‐bis(diphenylphosphino)butane ((S,S )‐DIOP)), and (R )‐2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl ((R )‐BINAP)) were used as optically active diphosphine ligands. The platinum‐containing catalytic systems provided surprisingly high activity. The hydroformylation selectivities of up to 97% were accompanied by perfect regioselectivity towards the dioxolane‐based linear aldehyde. The enantiomeric composition of all components in the reaction mixture was determined and followed throughout the reaction. The unreacted 4‐vinyl‐1,3‐dioxolan‐2‐one was recovered in optically active form. The kinetic resolution was rationalized using the enantiomeric composition of the substrate and the products.     

Axially Dissymmetric Chiral (R)‐N,W‐Bis(2‐hydroxy‐3,5‐ditert‐butyl‐arylmethyl)‐1, 1′‐binaphthalene‐2,2′‐diamine as Chiral Ligands in the Reaction of Diethylzinc to Aldehydes†

Chiral ligand (A)‐N,N′‐Bis(2‐hydroxy‐3,5‐di‐tert‐butyl‐arylmethyl)‐1,1′‐binaphthalene‐2,2′‐diamine derived from the reduction of Schiff base (R)‐2,2′‐bis (3,5‐di‐tert‐butyl‐2‐hydroxybenzylideneamino)‐1, 1′‐binaphthyl with LiAlH₄, is fairly effective in the asymmetric addition reaction of diethylzinc to aldehydes by which good yields (46%‐94%) of the corresponding sec‐alcohols can be obtained in moderate ee (51%‐79%) with R configuration for a variety of aldehydes.     

Synthesis and chiroptical properties of chiral binaphthyl‐containing polyfluorene derivatives

New chiral binaphthyl‐containing polyfluorene (PF) derivatives, PFOH , PFMOM , and PFP , bearing different binaphthyl units ((S)‐2,2′‐bis(methoxymethoxy)‐1,1′‐binaphthyl for PFMOM , (S)‐1,1′‐binaphthyl‐2,2′‐diol for PFOH , and (S)‐2,2′‐bis(diphenylphosphinyl)‐1,1′‐binaphthyl for PFP ) in the backbone have been designed and synthesized through Pd‐catalyzed Suzuki polycondensation. Their properties have been investigated in detail by ¹H NMR, ¹³C NMR, TGA, DSC, UV–vis, photoluminescence (in solutions, in thin films before and after annealing), and circular dichroism (CD) spectroscopic methods compared with poly(9,9‐dihexylfluorene‐2,7‐diyl) ( PF ). The resulting copolymers possessed excellent solubility in organic solvents and emitted strong blue light. The phosphine oxide‐containing copolymers PFP and PFMOM exhibited higher quantum yields and better thermal spectral stability in comparison with PF . All the copolymers exhibited obviously the linearly polarized photoluminescent properties both in solutions and in solid states. High emission polarization ratios (R_PL) of PFP were observed with no obvious decrease upon thermal annealing. In addition, investigation of the CD spectroscopic properties of these copolymers in THF solutions indicated that the chirality of the binaphthyls could be transferred to the whole PF backbone. All these results demonstrated that introduction of the chiral binaphthyls, particularly BINAPO, into the backbone could effectively improve the performances of the copolymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Ferrocenophanes with Interannular Nitrogen–Gallium Bridges. 1,3,2‐Diazagalla‐[3]Ferrocenophanes and an 1‐Aza‐3‐Azonia‐2‐Gallata‐[3]Ferrocenophane. Synthesis and Structure

1,1′‐Bis(trimethylsilylamino)ferrocene reacts with trimethyl‐ and triethylgallium to give the μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetraalkyldigallanes. These were converted into the 1,3‐bis(trimethylsilyl)‐2‐alkyl‐2‐pyridine‐1,3,2‐diazagalla‐[3]ferrocenophanes, of which the ethyl derivative was characterized by X‐ray structural analysis. Treatment of gallium trichloride with N,N′‐dilithio‐1,1′‐bis(trimethylsilylamino)ferrocene affords μ‐[ferrocene‐1,1′‐diyl‐bis(trimethylsilylamido)]tetrachlorodigallane along with bis(trimethylsilyl)‐2,2‐dichloro‐1‐aza‐3‐azonia‐2‐gallata‐[3]ferrocenophane as a side product, and both were structurally characterized by X‐ray analysis. The solution‐state structures of the new gallium compounds and aspects of their molecular dynamics in solution were studied by NMR spectroscopy (¹H, ¹³C, ²⁹Si NMR).     

Substituted 2,2′‐Bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyl Complexes of Zinc

The condensation reaction of 2,2′‐diamino‐4,4′‐dimethyl‐6,6'‐dibromo‐1,1′‐biphenyl with 2‐hydroxybenzaldehyde as well as 5‐methoxy‐, 4‐methoxy‐, and 3‐methoxy‐2‐hydroxybenzaldehyde yields 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyl ( 1a ) as well as the 5‐, 4‐, and 3‐methoxy‐substituted derivatives 1b , 1c , and 1d , respectively. Deprotonation of substituted 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls with diethylzinc yields the corresponding substituted zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls ( 2 ) or zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyls ( 3 ). Recrystallization from a mixture of CH₂Cl₂ and methanol can lead to the formation of methanol adducts. The methanol ligands can either bind as Lewis base to the central zinc atom or as Lewis acid via a weak O–H ··· O hydrogen bridge to a phenoxide moiety. Methanol‐free complexes precipitate as dimers with central Zn₂O₂ rings.     

Enantioselective Dehydrogenation of Alkan‐2‐ols by Gaseous (BINOLate)Ni+

Electrospray ionization of methanolic solutions of nickel(II) nitrate, 1,1′‐binaphthalene‐2,2′‐diol (BINOL), and secondary alcohols (ROH) inter alia affords monocationic complexes of the type [(BINOLate)Ni(ROH)]⁺, where BINOLate stands for singly deprotonated BINOL. Upon collision‐induced dissociation (CID), the mass‐selected ions undergo competing fragmentations involving loss of the alcohol ligand and expulsion of the corresponding carbonyl compound. The latter reaction leads to the hydride complex [(BINOL)Ni(H)]⁺ and can thus be regarded as the reversal of the reduction of ketones with metal hydrides. The possibility of the occurrence of enantioselective gas‐phase reactions is probed for combinations of chiral BINOLate ligands with chiral alkan‐2‐ols. Whereas aliphatic alkan‐2‐ols do not show pronounced chiral effects, enantioselective bond activation is observed for 1‐phenylethanol, indicating an interaction of the aromatic ring of the alkanol with the positively charged metal center.     

Halogenation of Fluorinated 1,3,5‐Triketones

The behavior of linear and cyclic fluorinated 1,3,5‐triketones and their metal derivatives towards common halogenating agents was examined, and optimal reaction conditions for the straightforward synthesis of mono‐, di‐, and tetrahalogenated products were found (Schemes 1–3). An aromatization through a double HBr elimination from an α,α′‐dibrominated cyclohexanone was shown to be a promising synthetic route to 1,1′‐(2‐hydroxy‐1,3‐phenylene)bis[2,2,2‐trifluoroethanones] (= 2,6‐bis(trifluoroacetyl)phenols; Scheme 4). Additionally, the 1,3,5‐triketones prepared add readily H₂O or alcohols to produce novel bridged 2,6‐dihydroxypyran‐4‐ones (Scheme 2). The structure of the obtained compounds 6a and 7a was confirmed by X‐ray structure analysis.     

An Efficient Five‐Component Reaction for the Synthesis of 4,4′‐((2‐Oxoindoline‐3,3‐diyl)bis(methylene))bis(2‐aryl‐1H‐pyrrolo[3,4‐c]quinoline‐1,3(2H)‐dione) Derivatives

An efficient cascade process five‐component reaction of isatins and 3‐oxo‐N‐arylbutanamide for the synthesis of 4,4′‐((2‐oxoindoline‐3,3‐diyl)bis(methylene))bis(2‐aryl‐1H‐pyrrolo[3,4‐c]quinoline‐1,3(2H)‐dione) derivatives was reported under mild condition. The advantages of this strategy are easy to obtain raw materials, convenient one‐pot procedure, and simple operation.     

Rhodium‐Catalyzed 1,4‐Addition of Lithium 2‐Furyltriolborates to Unsaturated Ketones and Esters for Enantioselective Synthesis of γ‐Oxo‐Carboxylic Acids By Oxidation of the Furyl Ring with Ozone

Rhodium‐catalyzed 1,4‐addition of lithium 5‐methyl‐2‐furyltriolborate ([ArB(OCH₂)₃CCH₃]Li, Ar=5‐methyl‐2‐furyl) to unsaturated ketones to give β‐furyl ketones was followed by ozonolysis of the furyl ring for enantioselective synthesis of γ‐oxo‐carboxylic acids. [Rh(nbd)₂]BF₄ (nbd=2,5‐norbornadiene) chelated with 2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (binap) or 2,3‐bis(diphenylphosphino)butane (chiraphos) gave high yields and high selectivities in a range of 91–99 % ee at 30 °C in a basic dioxane/water solution. The corresponding reaction of unsaturated esters, such as methyl crotonate, had strong resistance under analogous conditions, but the 1,4‐adduct was obtained in 70 % yield and with 94 % ee when more electron‐deficient phenyl crotonate was used as the substrate.     

Kinetic Resolution of 1,1′‐Biaryl‐2,2′‐Diols and Amino Alcohols through NHC‐Catalyzed Atroposelective Acylation

We present here a highly efficient NHC‐catalyzed kinetic resolution of a wide range of 1,1′‐biaryl‐2,2′‐diols and amino alcohols to provide them in uniformly ≥99 % ee. This represents the first highly enantioselective catalytic acylation of axially chiral alcohols. The aldehyde backbone that is incorporated into the chiral acyl azolium intermediate was found to have a significant effect on the enantioselectivity of the process.     

Capillary GC using pyridyl β‐cyclodextrin stationary phase

A new β‐CD derivative, heptakis [2,6‐di‐O‐pentyl‐3‐O‐(4′‐chloro‐5′‐pyridylmethyl)]‐β‐CD, was synthesized by the selective introduction of a pyridyl group on the 3‐positions of β‐CD. The chromatographic properties of the pyridyl β‐CD derivative were studied by using it as the stationary phase in capillary GC. The polarity of the prepared stationary phase was moderate, and the separation results demonstrated that the prepared stationary phase possessed excellent separation ability and chiral recognition for a wide range of analytes. Not only the aromatic positional isomers, such as o‐, m‐, p‐xylene and α‐, β‐naphthol isomers, but also some compounds with multi‐stereogenic centers, such as n‐(1‐methylpropyl)‐3‐(2,2‐dichloroethenyl)‐2,2‐dimethylcyclopropanecarboxamide and n‐(1‐methylpropyl)‐3‐(2‐chloro‐3,3,3‐trifluoropropenyl)‐2,2‐dimethylcyclopropanecarboxamide with three stereogenic centers including eight configurational isomers, were successfully separated. The results also indicated that the polarity of the β‐CD derivative, and the hydrogen bonding between the β‐CD derivative, and the analytes had a very important effect on separation.     

Polymer‐based fluorescence sensors incorporating chiral binaphthyl and benzo[2,1,3]thiadiazole moieties for Hg2+ detection

Three chiral polymers P‐1 , P‐2 , and P‐3 could be obtained by the polymerization of (R)‐6,6′‐dibutyl‐3,3′‐diiodo‐2, 2′‐binaphthol (R‐M‐1) , (R)‐6,6′‐dibutyl‐3,3′‐diiodo‐2,2′‐bisoctoxy‐1,1′‐binaphthyl ( R‐M‐2 ), and (R)‐6,6′‐dibutyl‐3,3′‐diiodo‐2,2′‐bis (diethylaminoethoxy)‐1,1′‐binaphthyl ( R‐M‐3 ) with 4,7‐diethynyl‐benzo[2,1,3]‐thiadiazole ( M‐1) via Pd‐catalyzed Sonogashira reaction, respectively. P‐1 , P‐2 , and P‐3 can show pale red, blue–green, and orange fluorescence. The responsive optical properties of these polymers on various metal ions were investigated by fluorescence spectra. Compared with other cations, such as Co²⁺, Ni²⁺, Ag⁺, Cd²⁺, Cu²⁺, and Zn²⁺, Hg²⁺ can exhibit the most pronounced fluorescence response of these polymers. P‐1 and P‐2 show obvious fluorescence quenching effect upon addition of Hg²⁺, on the contrary, P‐3 shows fluorescence enhancement. Three polymer‐based fluorescent sensors also show excellent fluorescence response for Hg²⁺ detection without interference from other metal ions. The results indicate that these kinds of tunable chiral polybinaphthyls can be used as fluorescence sensors for Hg²⁺ detection. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 997–1006, 2010     

Chiral discrimination of β‐3‐homo‐amino acids using the kinetic method

Chiral discrimination of seven enantiomeric pairs of β‐3‐homo‐amino acids was studied by using the kinetic method and trimeric metal‐bound complexes, with natural and unnatural α‐amino acids as chiral reference compounds and divalent metal ions (Cu²⁺ and Ni²⁺) as the center ions. The β‐3‐homo‐amino acids were selected for this study because, first of all, chiral discrimination of β‐amino acids has not been extensively studied by mass spectrometry. Moreover, these β‐3‐homo‐amino acids studied have different aromatic side chains. Thus, the emphasis was to study the effect of the side chain (electron density of the phenyl ring, as well as the difference between phenyl and benzyl side chains) for the chiral discrimination. The results showed that by the proper choice of a metal ion and a chiral reference compound, all seven enantiomeric pairs of β‐3‐homo‐amino acids could be differentiated. Moreover, it was noted that the β‐3‐homo‐amino acids with benzyl side chains provided higher enantioselectivity than the corresponding phenyl ones. However, increasing or decreasing the electron density of the aromatic ring by different substituents in both the phenyl and benzyl side chains had practically no role for chiral discrimination of β‐3‐homo‐amino acids studied. When copper was used as the central metal, the phenyl side chain containing reference molecules (S)‐2‐amino‐2‐phenylacetic acid (L ‐Phg) and (S)‐2‐amino‐2‐(4‐hydroxyphenyl)‐acetic acid (L ‐4′‐OHPhg) gave rise to an additional copper‐reduced dimeric fragment ion, [Cu^I(ref)(A)]⁺. The inclusion of this ion improved noticeably the enantioselectivity values obtained. Copyright © 2010 John Wiley & Sons, Ltd.     

Catalytic Asymmetric Ring‐Opening Reactions of Aziridines with 3‐Aryl‐Oxindoles

A highly enantioselective ring‐opening alkylation reaction between 3‐aryl‐oxindole and N‐(2‐picolinoyl) aziridine has been realized for the first time. The reaction is efficiently mediated by a simple in‐situ‐generated magnesium catalyst and 3,3′‐fluorinated‐BINOL (BINOL=1,1′‐binaphthalene‐2,2′‐diol) has been identified as a powerful chiral ligand. Notably, the fluorine atom on the chiral ligand plays a key role in providing the desired chiral 3‐alkyl‐3‐aryl oxindoles with excellent enantioselectivities.     

Synthesis and characterization of novel polyamide‐imides containing noncoplanar 2,2′‐dimethyl‐4,4′‐biphenylene unit

A new diimide‐dicarboxylic acid, 2,2′‐dimethyl‐4,4′‐bis(4‐trimellitimidophenoxy)biphenyl (DBTPB), containing a noncoplanar 2,2′‐dimethyl‐4,4′‐biphenylene unit was synthesized by the condensation reaction of 2,2′‐dimethyl‐4,4′‐bis(4‐minophenoxy)biphenyl (DBAPB) with trimellitic anhydride in glacial acetic acid. A series of new polyamide‐imides were prepared by direct polycondensation of DBAPB and various aromatic diamines in N‐methyl‐2‐pyrrolidinone (NMP), using triphenyl phosphite and pyridine as condensing agents. The polymers were produced with high yield and moderate to high inherent viscosities of 0.86–1.33 dL · g⁻¹. Wide‐angle X‐ray diffractograms revealed that the polymers were amorphous. Most of the polymers exhibited good solubility and could be readily dissolved in various solvents such as NMP, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide (DMF), dimethyl sulfoxide, pyridine, cyclohexanone, and tetrahydrofuran. These polyamide‐imides had glass‐transition temperatures between 224–302 °C and 10% weight loss temperatures in the range of 501–563 °C in nitrogen atmosphere. The tough polymer films, obtained by casting from DMAc solution, had a tensile strength range of 93–115 MPa and a tensile modulus range of 2.0–2.3 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 63–70, 2001     

Synthesis and characterization of two isostructural 3d–4f coordination compounds based on pyridine‐2,6‐dicarboxylic acid and 4,4′‐bipyridine

The design and synthesis of 3d–4f heterometallic coordination polymers have attracted much interest due to the intriguing diversity of their architectures and topologies. Pyridine‐2,6‐dicarboxylic acid (H₂pydc) has a versatile coordination mode and has been used to construct multinuclear and heterometallic compounds. Two isostructural centrosymmetric 3d–4f coordination compounds constructed from pyridine‐2,6‐dicarboxylic acid and 4,4′‐bipyridine (bpy), namely 4,4′‐bipyridine‐1,1′‐diium diaquabis(μ₂‐pyridine‐2,6‐dicarboxylato)tetrakis(pyridine‐2,6‐dicarboxylato)bis[4‐(pyridin‐4‐yl)pyridinium]cobalt(II)dieuropium(III) octahydrate, (C₁₀H₁₀N₂)[CoEu₂(C₁₀H₉N₂)₂(C₇H₃NO₄)₆(H₂O)₂]·8H₂O, (I), and 4,4′‐bipyridine‐1,1′‐diium diaquabis(μ₂‐pyridine‐2,6‐dicarboxylato)tetrakis(pyridine‐2,6‐dicarboxylato)bis[4‐(pyridin‐4‐yl)pyridinium]cobalt(II)diterbium(III) octahydrate, (C₁₀H₁₀N₂)[CoTb₂(C₁₀H₉N₂)₂(C₇H₃NO₄)₆(H₂O)₂]·8H₂O, (II), were synthesized under hydrothermal conditions and characterized by IR and fluorescence spectroscopy, thermogravimetric analysis and powder X‐ray diffraction. Both compounds crystallize in the triclinic space group P. The Eu^III and Tb^III cations adopt nine‐coordinated distorted tricapped trigonal–prismatic geometries bridged by three pydc^2? ligands. The Co^II cation has a six‐coordination environment formed by two pydc^2? ligands, two bpy ligands and two coordinated water molecules. Adjacent molecules are connected by π–π stacking interactions to form a one‐dimensional chain, which is further extended into a three‐dimensional supramolecular network by multipoint hydrogen bonds.     

The crystal structure,luminescence and nitrobenzene‐sensing properties of a two‐dimensional MnII coordination polymer based on 2,6‐bis(imidazol‐1‐yl)pyridine

A two‐dimensional Mn^II coordination polymer (CP), poly[bis[μ₂‐2,6‐bis(imidazol‐1‐yl)pyridine‐κ²N³:N^3′]bis(thiocyanato‐κN)manganese] [Mn(NCS)₂(C₁₁H₉N₅)₂]_n, (I), has been obtained by the self‐assembly reaction of Mn(ClO₄)₂·6H₂O, NH₄SCN and bent 2,6‐bis(imidazol‐1‐yl)pyridine (2,6‐bip). CP (I) was characterized by FT–IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The crystal structure features a unique two‐dimensional (4,4) network with one‐dimensional channels. The luminescence and nitrobenzene‐sensing properties were explored in a DMF suspension, revealing that CP (I) shows a strong luminescence emission and is highly sensitive for nitrobenzene detection.     

Dynamic Chirality Control of tropos DPCB‐digold Skeleton by Chiral Binaphthyldicarboxylate

The planar 3,4‐diphosphinidenecyclobutene (DPCB) can be remarkably twisted into a C₂‐type helical structure by dual coordination of a AuCl moiety. A prompt chirality control of the twisted DPCB skeleton ligated by the digold units affords the enantiopure structure by exchanging the chloride ligands for chiral [1,1′‐binaphthalene]‐2,2′‐dicarboxylate. The chirality of the diaurated 2,2′‐bis(diphenylphosphanyl)‐1,1′‐biphenyl (BIPHEP) system can be controlled prior to that of DPCB. Mixing of a DPCB‐bis(chlorogold) complex with the chiral silver salt dynamically leads to a single diastereomer, which was characterized by the ³¹P NMR spectrum and the CD couplet patterns in the visible (DPCB) area. The absolute configuration of the singly induced helical structure was assigned by the theoretical CD spectra determined by TD‐DFT calculations. Intramolecular alkoxycyclization of hexa‐4,5‐dien‐1‐ol catalyzed by the asymmetric DPCB‐digold structure were also attempted.     

Asymmetric anionic polymerizations of 7‐cyano‐7‐alkoxycarbonyl‐1,4‐benzoquinone methides

Asymmetric anionic polymerizations of 7‐cyano‐7‐alkoxycarbonyl‐1,4‐benzoquinone methides ( 1 ) with various alkoxy groups were performed using chiral initiators such as lithium isopropylphenoxide (ⁱPrPhOLi)/(S)‐(–)‐2,2′‐isopropylidene‐bis(4‐phenyl‐2‐oxazoline) ((–)‐PhBox) and lithium isopropylphenoxide (ⁱPrPhOLi)/(–)‐sparteine ((–)‐Sp) to investigate the effect of the alkoxy groups of alkoxycarbonyl substituent in the monomers 1 and chiral ligands of chiral initiators on the control of chiral center in the formation of polymers. Molar optical rotation values of the polymers were significantly dependent upon alkoxy groups, and the polymers with higher molar optical rotation were obtained in monomers with primary alkoxy groups. The asymmetric anionic oligomerizations of the quinone methides having methoxy( 1a ), ethoxy( 1b ), and n‐propoxy( 1c ) groups with chiral initiators were carried out. Both 1‐mers and 2‐mers were isolated and their optical resolutions were performed to determine the extent of stereocontrol. High stereoselectivity was observed at the propagation reaction, but not at the initiation reaction. The effect of the counterion on the control of chiral center in the formation of the polymer was investigated in the asymmetric anionic polymerizations of 1b with ⁱPrPhOM(M = Li, Na, K)/(–)‐Sp and ⁱPrPhOM(M = Li, Na, K)/(–)‐PhBox initiators and discussed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011