We have found a simple and novel synthetic method for obtaining chiral polymer from an achiral monomer by using catalytic system. The chirality of the was caused only one-handed helical backbone, had no other structures in side groups. In addition, conformation stable solution itself. This is first example helix-sense-selective polymerization substituted acetylene. stability helicity to be intramolecular hydrogen bonds.

Because of their unique structures and properties, π-conjugated polymers have attracted the attention scientists engineers. The authors studied synthesis two kinds poly(aromatic acetylene)s, i.e. poly(arylacetylene)s poly(aryleneethynylene)s with aim obtaining new having novel functions or higher performances. This review mainly concerns authors' results, as follows: first, we describe properties achiral poly(arylacetylene)s, containing trimethylsilyl groups, oligodimethylsiloxanyl dendritic...

A novel, highly selective photocyclic aromatization (SCAT) of π-conjugated polymers from phenylacetylene having two hydroxyl groups to exclusively yield a 1,3,5-trisubstituted benzene derivative was developed, and its success confirmed by (1)H NMR, GPC, TOF-MS. The SCAT reaction has many unique characteristics. (1) It is quantitative reaction: it gave only the corresponding cyclic trimer, i.e., derivative, quantitatively (100%). No byproducts were produced under best conditions. (2) an...

Abstract Poly[p-{L-(−)-menthoxycarbonyl}phenylacetylene]s prepared by [Rh(norbornadiene)Cl]2 as a polymerization catalyst exhibited much higher [α]D20 (= −605) than that(= −68.8) of the monomer and very high molar ellipticity(more 104) at π–π* region in CD spectrum: A chiral helical conformation main chain solution is suggested. The solid membrane this polymer showed enantioselective permeability (54%ee) for DL-tryptophan.

Optical resolution of various racemates such as (±)-tryptophan and (±)-1,3-butanediol was achieved by permeation through a self-supporting membrane (+)-poly{1-[dimethyl(10-pinanyl)silyl]-1-propyne} [(+)-poly(DPSP)] prepared homopolymerization (−)-1-[dimethyl(10-pinanyl)silyl]-1-propyne [(−)-DPSP]. Almost complete optical (% ee the permeate = 81−100% ee) at an initial period concentration-driven permeation, stable with moderate permselectivity 12−54% continued for more than 600 h. In...

Disubstituted acetylenes with chiral pinanyl groups, (−)-1-{4-[dimethyl(10-pinanyl)silyl]phenyl}-2-phenylacetylene (1), (−)-1-{3-[dimethyl(10-pinanyl)silyl]phenyl}-2-phenylacetylene (2), (−)-1-{4-[dimethyl(10-pinanyl)silyl]phenyl}-1-propyne (3), and (−)-1-chloro-2-{4-[dimethyl(10-pinanyl)silyl]phenyl}acetylene (4), polymerized NbCl5-, TaCl5-, or MoCl5-based catalysts to give high molecular weight polymers in good yields. Poly(1) poly(2) showed intense circular dichroism (CD) effects the...

In this study, we investigated the helix-sense-selective polymerizations of newly synthesized achiral phenylacetylenes having two N-alkylamide groups, such as 3,5-bis(dodecylamide)phenylacetylene (DAPA), 3,5-bis(octylamide)phenylacetylene (OAPA), and 3,5-bis(butylamide)phenylacetylene (BAPA), by using a chiral rhodium catalyst system ([Rh(nbd)Cl]2-(R)-(+)-1-phenylethylamine [(R)-PEA]). Poly(BAPA) was insoluble in any solvents. On other hand, poly(DAPA) poly(OAPA) were soluble toluene, THF,...

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTOptically Active Conjugated Polymer Nanoparticles from Chiral Solvent Annealing and NanoprecipitationHyojin KimHyojin KimSchool of Applied Chemical Engineering, Major in Science Kyungpook National University 1370 Sankyuk-dong, Buk-ku, Daegu 702−701, KoreaDaegu Technopark Nano Convergence Practical Application Center, 891−5 Daecheon-dong, Dalseo-ku, 704−801, KoreaMore by Hyojin Kim, Young-Jae JinYoung-Jae JinSchool Jin, Beomsu Shin-Il KimBeomsu Toshiki...

One of the authors discovered helix-sense-selective polymerization (HSSP) an achiral substituted phenylacetylene which has two hydroxymethyl groups and a relatively hydrophobic substituent by using chiral catalytic system in 2003. The one-handed helicity is stable static nonpolar solvents because it maintained intramolecular hydrogen bonds. Since resulting polymer extremely tight its main chain, shows many interesting unusual properties including highly selective photocyclic aromatization...

Although two-dimensional polymers (2DPs) and related materials are very attractive subjects for research because they expected to function as ideal gas separation membrane materials, we need answer some basic questions about them. For example, "Why not a common or popular topic, especially in textbooks?"; "How can be synthesized?"; "Whatever 2DPs? define 2DPs?" In this review, try these questions. First, the significance of 2DP molecular-sieving is explained Section 1. Second, definitions...

Abstract Absolute helix‐sense‐selective polymerization of an achiral acetylene monomer ( 1 ) in one‐handed helical channels created with decomposition (±)‐poly using circularly polarized light is realized no chiral compounds. In addition, the relative optical yield (%ee) formed oligomers controlled by those channels.

ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication the EditorNEXTEnantioselective Permeation through Membranes of Chiral Helical Polymers Prepared by Depinanylsilylation Poly(diphenylacetylene) with a High Content Pinanylsilyl GroupMasahiro Teraguchi, Jun-ichi Suzuki, Takashi Kaneko, Toshiki Aoki, and Toshio MasudaView Author Information Graduate School Science Technology, Niigata University, Ikarashi 2−8050, 950-2181, Japan, Center for Transdisciplinary Research, 2-8050,...

ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication the EditorNEXTPolydendron: Polymerization of Dendritic Phenylacetylene MonomersTakashi Kaneko, Takahiro Horie, Motohiro Asano, Toshiki Aoki, and Eizo OikawaView Author Information Graduate School Science Technology, Niigata University, Ikarashi 2-8050, 950-21, JapanCite this: Macromolecules 1997, 30, 10, 3118–3121Publication Date (Web):May 19, 1997Publication History Received18 November 1996Revised18 February 1997Published...

Two new chiral helical poly(hydroxyl-containing phenylacetylene) membranes without the coexistence of any other moieties were prepared in following manner: (1) synthesis and homo- or copolymerization two pinanylsiloxy-containing phenylacetylenes, (2) preparation self-supporting from (co)poly(chiral phenylacetylene)s by a solvent-casting technique, (3) depinanylsilylation preformed polymer situ. Complete was successfully achieved treating with trifluoroacetic acid. The resulting exhibited...

A poly(9,10-anthryleneethynylene)-based polyradical with two pendant stable phenoxyls in one anthracene skeleton was newly synthesized via polymerization of the corresponding bromoethynylanthracene monomer using a Pd(0) catalyst. The average molecular weight polymer reached M(n) = 5 x 10(3) and soluble common organic solvents. prepared from hydroxyl precursor appropriately at room temperature. ESR spectrum monomeric radical suggested an effectively delocalized spin density distribution on...

{4-[(3,5-Di-tert-butyl-4-hydroxyphenyl)(3,5-di-tert-butyl-4-oxocyclohexa-2,5-dienylidene)methyl]phenyl}acetylene (abbreviated as (4-ethynylphenyl)hydrogalvinoxyl) was polymerized using [Rh(norbornadiene)Cl]2 catalyst in the presence of (R)-1-phenylethylamine or (S)-1-phenylethylamine to give red polymers. The circular dichroism (CD) spectra polymers indicated that an excess one-handed helical polyacetylene backbone induced by helix-sense-selective polymerization under asymmetric condition...

To develop new phenylacetylene monomers more suitable for helix-sense-selective polymerization (HSSP) we reported previously and to improve the efficiency of HSSP membrane performance resulting polymers, novel phenylacetylenes having a flexible oligosiloxanyl group (SnBDHPA) together with other related three series were synthesized polymerized by using chiral catalytic system enantioselectivity in permeation membranes from polymers examined. SnBDHPA was most CD absorptions (G values)...

Abstract 4‐Alkyloxy‐3,5‐bis(hydroxymethyl)phenylacetylenes with eight types of alkyl groups were synthesized and polymerized a chiral catalytic system. We found that the length played very important role in achieving helix‐sense‐selective polymerization. Five polymerizations achieved resulting polymers whose chain was longer than six. think ‐ prevented from becoming insoluble by forming inter molecular hydrogen bonds between hydroxyl groups, stabilized their one‐handed helical structure...

S. Otsuka, Y. Tatsuno, M. Miki, T. Aoki, Matsumoto, H. Yoshioka and K. Nakatsu, J. Chem. Soc., Commun., 1973, 445 DOI: 10.1039/C39730000445

By using a living one-handed helical cis-transoidal poly(chiral substituted phenylacetylene) as polymer initiator (poly(1n)), helix-sense-selective polymerization (HSSP) of an achiral phenylacetylene 2 having two hydroxy groups successfully afforded diblock copoly(phenylacetylene) (copoly(1n/2m)) consisting dynamic block and static cis-cisoidal block. The formation the structure was confirmed by consumption chiral initiator, appearance characteristic CD indicating block, occurrence selective...

Commercially available molecular rotor (MR) compounds were recrystallized using chiral monoterpenes as solvents. The resulting crystals exhibited large circular dichroism signals with opposing signs according to the handedness of solvent used. X-ray crystallographic analysis showed that chirality originated from asymmetric restriction intramolecular rotation in crystals. also highly emissive due restricted bond rotation, while solutions materials almost nonemissive. solvent-to-MR transfer...