Synthesis of benzylidene-pendant polyphthalimidines from flexible bisphthalides and various diamines

New polyphthalimidine-forming monomers, 5,5′-(oxydi-p-phenylenedicarbonyl)bis(3-benzylidenephthalide) and the 6,6′-derivative, were synthesized by the Friedel–Crafts reaction of diphenyl ether with 5- and 6-chloroformyl-3-benzylidenephthalide, respectively. The direct polycondensation of these bisphthalides with both aliphatic and aromatic diamines in o-phenylphenol at 200–250°C afforded polyphthalimidines having inherent viscosities of 0.2–1.2 dL/g in almost quantitative yields. Syntheses of aliphatic polyphthalimidines with higher inherent viscosities were also achieved by a two-step procedure involving ring-opening polyaddition and subsequent thermal cyclodehydration. All the polymers were amorphous and readily soluble in N-methyl-2-pyrrolidone (NMP), m-cresol, nitrobenzene, pyridine, and chloroform. Tough and flexible films could be cast from NMP solutions of the polymers. Glass transition temperatures of the polyphthalimidines were in the range of 158–246°C. The thermogravimetry of the aromatic polymers showed 10% weight loss in air and nitrogen at 445–515 and 500–520°C, respectively. The crosslinking reaction of some benzylidenependant polyphthalimidines took place at 300°C through double-bond addition to afford cured polymers with improved thermal stability.     

Synthesis of benzyl substituted naphthalenes from benzylidene tetralones

A convenient and efficient synthesis of novel highly substituted dimethoxybenzylnaphthalenes, which are precursors to several dihydroxynaphthoic acids, is described. The approach involves the use of aldol chemistry to provide a number of benzylidene tetralones, which are converted to the target naphthalenes in three steps, with good to excellent yields. Grignard reaction of intermediate benzyl tetralones provided 1-substituted benzyl naphthalenes. The reported synthesis is flexible and scalable and provides access to naphthalenes having a variety of substitution patterns. These benzyl substituted naphthalenes are being converted to naphthoic acids and the bioactivities of these compounds are currently being investigated.     

Synthesis of certain benzylidene derivatives of lagochilin

Methods for preparing certain aromatic acetals of 3,15,16,18-tetrahydroxy-9,13-epoxylabdane are described. The structures of the resulting acetals are confirmed by IR and PMR spectra. Certain physicochemical constants of the compounds are presented.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 225–226, May–June, 2000.     

Synthesis of new ionic monomers fromα-bromomethacrylic acid

Conclusions We synthesized some new ionic vinyl monomers derived from -bromomethacrylic acid and a number of nitrogen- and sulfur-containing compounds that are capable of undergoing radical copolymerization.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 187–188, January, 1982.     

Synthesis of dithiocarbamate bearing azobenzene group and use for RAFT polymerization of vinyl monomers

A novel dithiocarbamate bearing azobenzene group, 2‐(phenylazo‐phenoxy‐carbonyl) prop‐2‐yl 9H‐carbazole‐9‐carbodithioate (APCDT), was synthesized and used as a RAFT agent in the polymerization of methyl methacrylate (MMA). The results showed that the controllability to the polymerization of MMA was promoted with APCDT as RAFT agent compared to 2‐(ethoxycarbonyl) prop‐2‐yl 9H‐carbazole‐9‐carbodithioate (EPCDT) under the same experimental conditions. The reason was attributed to the higher chain transfer constant of APCDT than that of EPCDT in the presence of more bulkier and more electrophilic azobenzene moiety. In addition, the RAFT polymerizations of St and methylacrylate (MA) using APCDT as the RAFT agent were also carried out. The ultraviolet spectrum and fluorescence spectrum of the obtained polymers were investigated. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2886–2896, 2007     

Synthesis and properties of three novel series of monomers containing para-methoxyazobenzene as the mesogenic group

Three novel series of monomers, namely n-1-bromo-[4-(4-methoxyphenylazo)phenyloxy]-alkanes (Bn, n = 3, 6, 10), n-[4-(4-methoxyphenylazo)phenyloxy]alkyloxy-4-methoxybenzene (Cn, n = 3, 6, 10) and n-[4-(4-methoxyphenylazo)phenyloxy]alkyloxy-[4-methoxy-2,5-bis(chloromethyl)]benzene (Dn, n = 3, 6, 10) were synthesized and characterized with FTIR, ¹H NMR, UV-visible and fluorescence spectroscopy. Their thermal behaviour was studied by different scanning calorimetry and polarizing optical microscopy. The results show that B3, B6 and C6 exhibit monotropic nematic liquid crystalline behaviour.     

Synthesis and properties of three novel series of monomers containing para-methoxyazobenzene as the mesogenic group

Three novel series of monomers, namely n-1-bromo-[4-(4-methoxyphenylazo)phenyloxy]-alkanes (Bn, n = 3, 6, 10), n-[4-(4-methoxyphenylazo)phenyloxy]alkyloxy-4-methoxybenzene (Cn, n = 3, 6, 10) and n-[4-(4-methoxyphenylazo)phenyloxy]alkyloxy-[4-methoxy-2,5-bis(chloromethyl)]benzene (Dn, n = 3, 6, 10) were synthesized and characterized with FTIR, ¹H NMR, UV-visible and fluorescence spectroscopy. Their thermal behaviour was studied by different scanning calorimetry and polarizing optical microscopy. The results show that B3, B6 and C6 exhibit monotropic nematic liquid crystalline behaviour.     

Synthesis of ligand monomers derived from 4,5-diazafluoren-9-one

This report describes a convenient two-step synthesis of free radical polymerizable ligand monomers starting from 4,5-diazafluoren-9-one.     

Synthesis of fluorinated difunctional monomers

In order to obtain fluorinated difunctional monomers for fluoropolyurethanes, we synthesized novel fluorinated aliphatic diisocyanates [OCNCH₂(CF_c2)_nCH₂NCO] from corresponding diols [HOCH₂CH₂(CF₂)_nCH₂CH₂OH]. Oxidation of the diols with chromium trioxide-sulfuric acid gave α, α, ω, ω-tetrahydroperfluoroalkylene dicarboxylic acids in high yields. Then treating the acids with phosphorus pentachloride afforded corresponding dicarboxyl chlorides, which are easily converted to dicarboxyl azides with hydrazoic acid-pyridine complex. Finally, on Curtius rearangement of the azides, the end products, α, α, ω, ω-tetrahydroperfluoroalkylene diisocyanates were obtained in 53% (n=4) and 19% (n=6) yields from the starting diols.     

Synthesis and properties of liquid crystal monomers containing a reactive group in the lateral substituent

A series of nematic liquid crystal (LC) monomers containing a reactive group (double bonds) in the lateral substituent was designed and synthesised. Length of the lateral substituted groups that have one double bond varied from 1 to 4 methylene units. Length of the terminal substituted groups varied from 2 to 5 methylene units. The molecular structures of the intermediates and the LC monomers were characterised by Fourier transform infrared spectroscopy (FT-IR), elemental analysis and nuclear magnetic resonance (NMR) spectroscopy. The thermal phase behaviour of the monomers was investigated by differential scanning calorimetry (DSC) and polarised optical microscopy (POM) coupled with hot stage. Some molecules (V₁₅, V₂₅) with high aspect ratio exhibit enantiotropic nematic mesophase. The other compounds (V₁₂, V₂₂, V₄₂, V₄₃) show monotropic nematic mesophase during cooling. The relationship between the structure and mesomorphic property is also discussed.     

Synthesis of New Benzoxaphosphole Derivatives from the Reaction of Dialkylphosphonates and Trisdialkylaminophosphines with 2,6-Bis(benzylidene)cyclohexanones

The reaction of 2,6-bis(benzylidene)cyclohexanones with dialkylphosphonates and tris(dialkylamino)phosphines afforded the new benzoxaphosphole derivatives (5a–5d) and (9a–9f). The biological activity of the newly synthesized compounds was also examined. Possible reaction mechanisms are considered, and the structural assignments are based on analytical and spectroscopic results. The structure of the new benzoxaphosphole 5a was confirmed by a single crystal X-ray determination.     

Synthesis and characterization of optically active polyamides derived from carbohydrate-based monomers

The synthesis of three new stereoregular AB-type polyamides based on D -ribono-1,4-lactone, L -arabinose, and D -xylose has been carried out by the active ester polycondensation method. These polyamides were characterized by elemental analysis, IR and NMR spectroscopies, and powder X-ray diffraction. They displayed optical activity and had a pronounced affinity to water, although they were not soluble in this solvent. The polyamide obtained from D -ribono-1,4-lactone was highly crystalline and yielded films with spherulitic texture. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3645–3653, 1997     

Synthesis and polymerization of fluorinated monomers bearing a reactive lateral group 13. Copolymerization of vinylidene fluoride with 2-benzoyloxypentafluoropropene

The synthesis of 2-benzoyloxypentafluoropropene (BPFP) and its radical copolymerization with vinylidene fluoride (VDF), initiated by tert-butyl peroxypivalate is presented. In a first step, the preparation of two monomers [F₂CC(CF₃)OCOR were R stands for CH₃ or C₆H₅] was attempted. In contrast to the acetoxy derivative that could not be isolated, the benzoyl monomer was purified and then copolymerized with VDF. A series of 11 copolymerization reactions was achieved starting from initial [VDF]₀/([BPFP]₀+[VDF]₀) molar ratios ranging from 19 to 99 mol%. The molar compositions of the obtained copolymers were assessed by means of ¹⁹F nuclear magnetic resonance spectroscopy. From the Tidwell and Mortimer method, this kinetics of copolymerization led to the determination of the reactivity ratios, r_i, of both comonomers (r_VDF=0.77±0.40 and r_BPFP=0.11±0.32). Hence, the Alfrey and Price equation enabled one to assess the Q and e parameters of BPFP as follows: 0.019 (from Q_VDF=0.008), 0.043 (from Q_VDF=0.015) or 0.182 (from Q_VDF=0.036) and 1.97 (vs e_VDF=0.40), 2.07 (vs e_VDF=0.50) or 2.77 (vs e_VDF=1.20), respectively. These Q-e parameters and r_i were compared to those of other fluoroalkenes and are discussed.     

Synthesis of aminimide monomers and polymers

A convenient and practical synthesis of trimethylamine acrylimide, 1 , starting from 1, 1, 1-trimethylhydrazinium p-toluenesulfonate, 3 , and 3-chloropropionyl chloride is described. The intermediate, trimethylamine 3-chloropropionimide, 2 , is easily transformed into 1 either through a single-step dehydrohalogenation or through a two-step process consisting of very facile thermal rearrangement to 1,1,1-trimethylacrylylhydrazinium chloride, 4 , and subsequent deprotonation. Two new polymerizable monomers, 5 , and 6 , containing aminimide functionality were synthesized from trimethylamine imine, 7 , and the appropriate vinyl oxazolones, 8 , and 9 . Synthesis of hitherto unreported trimethylamine chloroacetimide, 10 , which offers unique opportunities for incorporating water-solubilizing and alkali-stable aminimide functionality into a variety of structures through nucleophilic displacement, is also described.     

Synthesis and reactivity of metal-containing monomers

The polymerization of diacrylates of the nontransition metals Mg, Zn, Ba, and Pb, which proceeds at low temperatures (5–10°C) with the complexes of alkylcobalts with tridentate Shiff bases (RCo) as initiators, was studied. The radical mechanism of the process was proved with the aid of free radical scavengers. The polymerization kinetics is given by the equationW _n = k [M] · [RCo]^0.75. The influence of the nature of the metal in the monomer and the alkyl ligand in the initiator on the polymerization process was discussed. Low temperatures promote the formation of polymers with high molecular weights and a predominantly syndiotactic structure. The effect of the steric hindrances arising during polymerization due to the formation of a three-dimensional cross-linked structure in the metal-containing polymer on the microstructure of polymer chain and on polymerization kinetics was considered.For part 24 seeBull. Acad. Sci., Div. Chem. Sci., 1992, 1609.For a preliminary communication see Ref.1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 500–503, March, 1993.