Synthesizing linearly

Amb and Rasmussen attempted to synthesize linear polymer 25 by two different electrochemieal methods, anodie polymerization of [Bu4N][4a] in a number of solvents, and eathodic polymerization of [Bu4N][4e] in the presence of [Ni(bpy)3][PFg]2 in a 0.1 M BU4NPF6 diehloromethane solution. The... 

In the field of polymer science, the most extensively used transferase is phosphorylase (systematic name (1 4)-a-D-glucan phosphate a-D-glucosyltransferase EC 2.4.1.1). Although this enzyme is responsible for the depolymerization of linear a-( 1 4) glycosidic chains in vivo it can also be used to synthesize linear a-( 1 4) glycosidic chains (amylose) in vitro. 

Now that methods have been developed for synthesizing linear and isotactic polymers, the possibility of creating highly crystalline polymers exists. Coupled with more reliable methods of estimating the extent of crystallinity, polymers can now be better characterized than formerly, thus making more significant low temperature specific heat measure-... 

In order to investigate the possibility of synthesizing linear N6 (still experimentally unknown), the following reaction scheme (Eq. 2) was proposed by Mezey... 

One of the pioneers in designing high-temperature, high-performance polymers was Carl Speed Marvel (1894-1988). Marvel obtained his PhD in organic chemistry from the University of Illinois, where he then spent 41 years as a faculty member in the chemistry department. One of the first students in his organic class was Wallace Carothers, who was just beginning his doctoral studies. Marvel soon became interested in polymers, and was probably the first person to synthesize linear polyethylene, although he did not pursue it. 

The reaction shown in Eq. (4) (X=halogen, OR Me=MgCl, Li, Na) was used to synthesize linear fully methylated carbosilanes (me = CH3). By the reaction... 

A similar technique is used in the industrial preparation of polarizing films. Amon and Kane21) impregnated an organic plastic film successively with solutions of rubean-ate and copper salts to synthesize linear polymers in this film. These polymers become oriented to give the polarizing film when the latter is stretched in one direction. 

For the synthesis of glycogen-type polysaccharides from a-n-glucopyran-osyl phosphate, two enzymes are required. Phosphorylases, in presence of a suitable primer, synthesize linear chains of -( —> 4)-linked n-glucose residues these are then converted into a branched polysaccharide by a branching enzyme. ... 

For the production of ethylene/l-octene copolymers, metallocenes in combination with oligomeric methylalumoxanes or other compounds are now used [31, 63]. Half-sandwich transition metal complexes such as [(tetramethyl- / -cyclopentadienyl) (A-/-butylamido)dimethylsilyl]titanium dichloride are applied to synthesize linear low-density copolymers and plastomers, called constrained geometry catalysts [31]. Ethylene and styrene can be copolymerized to products ranging from semicrystalline mbber-like elastomers to highly amorphous rigid materials at room temperature [64]. 

We strongly encourage reducing the substitution of the resin for tetrameric peptide synthesized linearly, longer molecules (>30 residues) or for peptides rich in -structural elements to a substitution value lower than 0.25mmol/g of resin. 

Peters and Peters applied similar chemistry to synthesize linear dil enzo hcierocycles terminating in a quinoxalinc system <0IJHC1055>. Fused quinoxalines 245 were prepared from the condensation of 1,2-phcnylenediamine 242 with 1,2-dicarbonyl compounds 244. 

Chen et al. developed a strategy for preparing cyclic peptides via in situ generation of a thioester resulting from disulfide reduction subsequent NCL results in the desired peptide (Fig. 12) [76]. This strategy was used to synthesize linear glycopeptides, which, after thioester formation, resulted in cyclization to form a model glycopeptide in 73% yield (Scheme 8). 

Our overall objective is to explore the utility of the [2ti + 2tc + 2%] (homo Diels-Alder) cycloaddition reactions of norbomadiene as a route to synthesizing linearly and angularly fused polycyclic natural products... 

The difference between synthesizing linear or zigzag chains comes in general from the shape of the organic ligand. 

Two different approaches can be used to synthesize linear CD-based polymers. The first one consists in initially synthesizing CD-monomers that can be engaged in a polymerization process to obtain CD-based polymers. Classic CD functionalizations are generally made with acrylates or vinyl derivatives (see next section) [8]. The second method consists in reacting native or modified CDs with an already synthesized polymer to functionalize it (see next section). 

Tsekos 1., Okuda K., and Brown, Jr. R.M. 1996. The formation and development of cellulose-synthesizing linear terminal complexes (TCs) in the plasma membrane of the marine red alga Erythrocladia suhintegra Rosenv. Protoplasma 193 33 5. 

The copolymerization of ethylene with polar monomers is one potential method of improving various properties of PE [146, 147]. ADMET offers a method of synthesizing linear polymers identical to sequence-specific or random copolymers of ethylene and polar monomers with a variety of comonomer compositions. 

---