Benzyl Acrylate Research Articles

Asymmetric induction in the cycloaddition of 1,3-butadiene to a polymer-bound chiral acrylate

Crosslinked polystyrene resins containing pendant benzyl acrylate or chiral acrylates derived from R-(−)-1,3-butanedoil reacted with 1,3-butadiene or 2,3-dimethyl-1,3-butadiene in the presence of the Lewis acid catalysts TiCl 4, TiCl 3(OiPr), or TiCl 2(OiPr) 2 to yield Diels-Alder adducts. Cleavage of the adducts gave racemic or optically active 3-cyclohexen-1-ylmethanol and 3,4-dimethyl-3-cyclohexen-1-ylmethanol. The polymerbound Diels-Alder reactions were compared with their analogous reactions in solution. In reactions leading to optically active products the enantiomeric excesses on the polymer were at least as high as those performed in solution.

ChemInform Abstract: Cycloaddition Reactions of Oximes. Powerful New Carbon‐Carbon Bond Forming Methodology.

AbstractThe oximes (I), (V), (VIII), and (X) react with benzyl acrylate (IIa), phenyl vinyl sulfone (IIb), or the 2‐allylacrylate (XII) to give isoxazole derivatives via cycloaddition and Michael addition processes.

Synthesis of a New Class of Side Chain Liquid Crystal Polymers—Polymers with Mesogens Laterally Attached Via Short Linkages to Polymer Backbones

Abstract New monomers, 2,5-(4-alkoxybenzoyl-oxy)benzyl acrylates were synthesized. Upon radical polymerizations of these monomers thermotropic liquid crystalline polyacrylates with mesogens laterally attached to polymer backbones via short linkages were obtained. The polymers were found non-crystalline by WAXS measurements. Above glass transition all the polymers had a stable mesophase as revealed by DSC and a polarizing microscope. The glass transition and the isotropization temperatures were about 100°C and about 165°C respectively, both varying with the size of the R substituents in the mesogens. The term “mesogen-jacketed polymer” is proposed to describe this type of polymers of which the main chains are jacketed with laterally substituted mesogens and to distinguish this new class of side chain liquid crystal polymers from the conventional ones.

Radical copolymerization of acrylic monomers. VIII. Copolymerization of methyl methacrylate with methyl α‐p‐chlorobenzylacrylate and methyl methacrylate with methyl α‐p‐methoxybenzylacrylate

AbstractFree‐radical copolymerization of methyl methacrylate with methyl α‐p‐chlorobenzylacrylate and methyl methacrylate with methyl α‐p‐methoxybenzylacrylate have been studied in benzene solution at 40°C. Although a simple copolymerization model fits the composition data, the kinetic behavior of both copolymerization systems are analyzed from simple and reversible copolymerization models, taking into account the relatively low ceiling temperature of both methyl α‐(p‐substituted benzyl)acrylates and considering that the overall rate of copolymerization drastically decreases with the increase of the corresponding methyl α‐(p‐substituted benzyl)acrylate molar fraction in the feed.

Synthesis and free-radical polymerization of methyl α( p-substituted benzyl)acrylates

Methyl α- p-chlorobenzylacrylate and methyl α- p-methoxybenzylacrylate were synthesized from dimethylmalonate by well known organic reactions. Both monomers were polymerized by a free-radical mechanism in benzene and their ceiling temperature determined. Comparison of the ceiling temperatures with that of methyl α-benzylacrylate seems to indicate that the differences in entropic factor for the polymerization of methyl α( p-substituted benzyl)acrylates might be related to the differences in ceiling temperatures.

Polymeric reaction of acrylic polymer–monomer system irradiated by low‐energy electron beam. II. Effect of ester structure of acrylic polymer

AbstractPolymeric reactions of polyacrylate–benzyl acrylate (BzA) systems induced by a low‐energy electron beam were investigated by changing the species of polyacrylates added to the system. The gel fraction, the proportion of BzA units incorporated into gel by infrared (IR) analysis, and the molecular weight and its distribution curves by gel permeation chromatography (GPC) were examined to elucidate the reaction mechanism for the polymer–monomer system. The GPC curves were detected by both ultraviolet (UV) and refractive index (RI). As the UV‐detected GPC curves represent the benzyl groups of graft polymers and homo polymers, the polymerization reactions can be followed by GPC. Ester structures of acrylic polymers were varied in order to examine how much the ester group affects such individual reactions as crosslinking, graft polymerizations, and homopolymerizations. In the case of both polyisobutylacrylate–BzA and poly(isoamyl acrylate)–BzA systems, the crosslinking and graft reactions predominated, while in the case of poly(t‐butyl acrylate)–BzA systems, homopolymerization was the main reaction. These results can be explained by the structure and reactivity of polymer radicals and viscosity of the system.

Polymeric reaction of acrylic polymer–monomer system irradiated by low energy electron beam. I. Effects of molecular weight of polymer and polymer‐to‐monomer ratio

AbstractPolymeric reaction of the poly(n‐butyl acrylate) (PBA)–benzyl acrylate (BzA) system induced by a low‐energy electron beam was investigated. In order to elucidate the reaction behavior of the PBA–BzA system, the gel fraction, molecular weight of soluble part, and molecular weight distributions were examined by means of gel permeation chromatography (GPC) equipped with both ultraviolet (UV) and refractive index (RI) detectors. RI‐detected GPC curves represented the molecular weights and their distributions of the total polymers, graft polymer, homopolymer, and unreacted PBA, while UV‐detected curves only corresponded to the benzyl groups of graft polymer and homopolymer. Thus, the reaction behavior of the system was able to be followed by GPC. The molecular weight of the added PBA and the mole ratio of PBA/BzA were varied. The crosslinking, the graft reaction and the homopolymerization of BzA proceeded competitively during the polymeric reaction. The proportions of BzA unit incorporated into the crosslinked, graft and homo polymers were estimated by combining of measurement of gel fraction, UV‐detected GPC curves, and infrared (IR) spectrum of gel. It was revealed that in the system containing PBA with high molecular weight, the grafting, and the crosslinking reactions predominated. The main reaction was the grafting in the system with a high mole ratio of PBA/BzA, while it was the homopolymerization in the systems with the low mole ratio of PBA/BzA. The reaction mechanism is discussed on the basis of reactivity and mobility of polymer radicals.

Studies on the light-focusing plastic rod 17: Plastic GRIN rod lens prepared by photocopolymerization of a ternary monomer system

Plastic GRIN rod lenses have been fabricated by photocopolymerization of ternary monomer systems. To select the monomer appropriate to photocopolymerization, we developed a computer program to predict the physical constants of the homopolymer from the chemical structure. Furthermore, according to the model of the gradient-index formation, methyl methacrylate (MMA)–acrylonitrile–vinyl benzoate (VB) monomer system and MMA–benzyl acrylate–VB monomer system were chosen as suitable systems. In both monomer systems, plastic GRIN rods with good lens functions up to the periphery were successfully obtained.

Synthesis of novel β-lactamase inhibitors from clavulanic acid. Preparation and chemical reactions of (5R)-3-vinyl-4-oxa-1-azabicyclo[3.2.0]hept-2-en-7-one

Three methods for the preparation of (5R)-3-vinyl-4-oxa-1-azabicyclo[3.2.0]hept-2-en-7-one (2) have been developed; the most convenient method involves the reaction of clavulanic acid with NN-dimethylformamide dimethyl acetal. Hydrogenation of the diene (2) gave three products: (3S,5R)-3-ethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one and (E)- and (Z)-(5R)-3-ethylidene-4-oxa-1-azabicyclo[3.2.0]heptan-7-one. Reaction of the diene (2) with methanol gave 4-methoxy-1-(2-oxobut-3-enyl)azetidin-2-one and 2-hydroxy-3-methoxy-3-vinyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one and with both acetic acid and thiophenol, it gave products derived from reaction at the β-lactam moiety.Thiophenol and oxygen reacted with the diene (2) to give a single 1,4-addition product, (Z)-(2S,5R)-3-(2-hydroxyethylidene)-2-phenylthio-4-oxa-1-azabicyclo[3.2.0]heptan-7-one and with thiophenol in the presence of a free-radical initiator, it gave three 1,4-addition products: (Z)-(5R)-3-(2-phenylthioethylidene)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one and (E)- and (Z)-(2S,5R)-3-ethylidene-2-phenylthio-4-oxa-1-azabicyclo[3.2.0]heptan-7-one.Tetracyanoethylene, maleic anhydride, diethyl azodicarboxylate, singlet oxygen, acrylaldehyde, and nitroso-benzene all reacted with the diene (2) to give Diels–Alder adducts. With benzyl acrylate, (2) gives three adducts: benzyl (1S,5R,11S)-3-oxo-6-oxa-2-azatricyclo[5.4.0.02,5]undec-7-ene-11-carboxylate and benzyl(1S,5R,10R)- and (1S,5R,10S)-3-oxo-6-oxa-2-azatricyclo[5.4.0.02,5]undec-7-ene-10-carboxylate. Some of the above 1,4-addition products and Diels–Alder adducts were found to be β-lactamase inhibitors.

Regioselectivity in cycloaddition reactions on solid phases

A 1% crosslinked divinylbenzene-styrene copolymer, incorporating benzyl acrylate groups, reacted in normal Diels–Alder reactions with E-1-phenyl-1,3-butadiene or methyl E-2,4-pentadienoate to give their respective polymer-bound benzyl cyclohexenecarboxylates. Polymer-bound benzyl propiolate and polymer-bound benzyl phenylpropiolate reacted with benzonitrile oxide in a typical 1,3-dipolar addition reaction to give their respective polymer-bound isoxazoles. Cleavage of the polymer-bound Diels–Alder adducts and the polymer-bound 1,3-dipolar addition adduct derived from polymer-bound benzyl propiolate gave mixtures of ortho and meta regiomers similar to those produced in analogous reactions in solution. Cleavage of the polymer-bound 1,3-dipolar addition adduct, derived from polymer-bound benzyl phenylpropiolate, followed by esterification, gave a solitary adduct, 4-carbomethoxy-3,5-diphenylisoxazole, but an analogous solution 1,3-dipolar addition yielded a 1:1 ratio of the two possible regiomers.

Attempted anionic homo‐ and copolymerization of vinylcymantrene, ferrocenylmethyl acrylate, η6‐(benzyl acrylate)‐tricarbonylchromium, and η4‐(2,4‐hexadien‐1‐yl methacrylate)‐ tricarbonyliron

Attempted anionic homo‐ and copolymerization of vinylcymantrene, ferrocenylmethyl acrylate, η⁶‐(benzyl acrylate)‐tricarbonylchromium, and η⁴‐(2,4‐hexadien‐1‐yl methacrylate)‐ tricarbonyliron

On the mechanism of isomerization in the esters of some α,β‐unsaturated carboxylic acids—II

AbstractThe effect of a phenyl group on the mechanisms of isomerization in the ionized methyl esters of simple α,β‐unsaturated acids (methyl acrylate and related compounds) has been investigated with the aid of deuterium labelling as well as information from mass analysed ion kinetic energy spectra and first field free region metastable peak shapes. Substitution of a hydrogen atom of the OCH3 group by a phenyl group (benzyl acrylate and homologues) greatly enhances the rate of [ester] → [acid] isomerizations (loss of H2O and COOH˙). It is inferred that this is due to an accelerating effect of the phenyl group on the first and the third steps (ring opening of the key intermediate ion which has the structure of the ionized enol form of γ‐butyrolactone) of the reaction whose mechanism is basically the same as that in methyl acrylate. A phenyl group present at the α‐ or β‐position of the vinylic double bond appears to suppress the [ester] → [acid] isomerization in some compounds by promoting other reactions or opening up a new reaction pathway, i.e. the loss of CH2O from ionized methyl atropate for which mechanisms are proposed.

Arenemetal complexes : VIII. Preparation of (η 8-alkenylbenzene)dicarbonylchromium complexes

Several (η 8-alkenylbenzene)dicarbonylchromium complexes (arenechelate complexes) were prepared in fair yield by the photolysis in ether of the tricarbonylchromium complexes of benzonorbornadiene ( syn-isomer), dibenzobicyclo[2.2.2]octa-2,5,7-triene ( syn-isomer), 4-phenyl-1-butene, 4-phenyl-1-butene-4,4- d 2, 5-phenyl-1-pentene, allyl phenyl ether, and benzyl vinyl ether. All of these arenechelate complexes are relatively stable and their IR, NMR, and mass spectral data are presented. Photolysis of the tricarbonylchromium complexes of benzobicyclo[2.2.2]octa-2,5-diene ( syn-isomer), 1,4-dihydronaphthalene, 3-phenyl-1-propene, 6-phenyl-1-hexene, and benzyl acrylate lead to decomposition and no arenechelate complexes. It is concluded that this method of preparation of arenechelate complexes is fairly general but there are some limitations that are apparent from the tricarbonylchromium complexes studied which failed to produce arenechelate complexes.

One-dimensional order in atactic polyacrylates containing aromatic side groups

To help in the understanding of the relations between chemical structure and morphological order in polymers of the type of poly( p-biphenyl acrylate) (PPBA), some polymers of similar structure have been synthesized and some of their physical properties studied. These polymers are: poly( p-biphenyl methacrylate), poly(vinyl p-phenyl benzoate), poly( p-phenyl benzyl acrylate), poly( p-benzyl phenyl acrylate) and poly( p-cyclohexyl phenyl acrylate) (PPCPA). Only PPCPA has been shown to possess a one-dimensional order in the solid state for reasons which are briefly discussed. The effect of copolymerization on the structural order of PPBA has also been given preliminary study. Copolymers of p-biphenyl acrylate (PBA) with p-biphenyl methacrylate (PBMA), N-vinyl carbazole (NVC) and p-cyclohexyl phenyl acrylate (PCPA) have been prepared and their properties have been studied by DSC and X-ray techniques. Small concentrations of PBMA or NVC units are sufficient to cancel the order of PPBA. On the contrary, copolymers of PBA and PCPA of any composition display morphological order in the solid state.

A simple method of determining copolymerization reactivity ratios by means of a computer

A Fortran IV program for determining copolymerization reactivity ratios is proposed. The program is based on the curve-fitting method and has the advantage of delivering values free of personal judgement. To check its validity the system benzylacrylate (BeA)/methylmethacrylate (MMA) was investigated. The reactivity ratios obtained from the Fineman-Ross plots ( r 1 = 0 · 34 ± 10 per cent and r 2 = 1 · 7 ± 10 per cent) are in good agreement with values obtained by using the proposed method ( r 1 = 0 · 36 and r 2 = 1 · 78).

Organometallic Polymers. XIII. Addition Polymerization and Copolymerization of π-(Benzyl acrylate)chromium Tricarbonyl

Organometallic Polymers. XIII. Addition Polymerization and Copolymerization of π-(Benzyl acrylate)chromium Tricarbonyl

Kinetics of polymerization of benzyl acrylate in bulk

AbstractThe kinetics of polymerization of benzyl acrylate has been studied at 55, 60, and 65°C with azobisisobutyronitrile as initiator. The overall rate of polymerization, degree of polymerization, chain transfer due to monomer, and the ratio of propagation and termination constant were calculated. The overall activation energy, the difference between the activation energy of propagation and termination, and the frequency factor are also reported.

The thermal degradation of poly(benzyl acrylate)

The thermal degradation of poly(benzyl acrylate) at 260° to 300° C has been studied. The main products of degradation are carbon dioxide, benzyl alcohol and low polymer. The main polymer chain backbone decomposes in an essentially random manner. In the light of spectroscopic data on the polymeric residue reaction mechanisms to explain the breakdown are considered. The pyrolysis of poly(benzyl acrylate) appears to follow a pattern similar to that of poly(methyl acrylate).

Gamma irradiation of polymers of arly and alkary methacrylates and acrylates

AbstractPoly(benzyl methacrylate) and poly(phenyl methacrylate) appear to degrade exclusively on gamma irradiation; energies for main‐chain, carbon‐carbon bond breaking are 711 and 228 e.v., respectively, which indicates a strong protective effect of the benzene ring. Poly(phenyl acrylate) requires higher doses to cause gelation than do poly(benzyl acrylate) and poly(phenylethyl acrylate), the latter behaving similarly to poly(n‐alkyl acrylates). Absence of hydrogen on the carbon adjacent to the ester link appears to be required to affect the radiation behavior of polyacrylates.