Speros, Bryan D. White, Yanfei Wu, Elizabeth A. Jackson, Bradley S. Slowinski, C. Macromolecules , 45 5 , Ana M. Chemical Reviews , 8 , Organometallics , 29 15 , Macromolecules , 42 14 , Macromolecules , 0 proofing DOI: Macromolecules , 41 21 , Kayo Terada, Erik B. Berda, Kenneth B. Wagener, Fumio Sanda and Toshio Masuda.
Macromolecules , 41 16 , Sirajud D. Khaja,, Sungmun Lee, and, Niren Murthy. Biomacromolecules , 8 5 , Violeta I. Petkovska,, Timothy E. Hopkins,, David H. Powell, and, Kenneth B. Analytical Chemistry , 78 11 , Stephen E.
Lehman, Jr. Organometallics , 24 7 , Haihu Qin,, Brian J. Chakulski,, Ingrid A. Mather, , Gregory S. Constable and, E. Bryan Coughlin. Macromolecules , 37 14 , Debra Tindall and, Kenneth B. The product was vacuum distilled through a short path vacuum distillation apparatus. The product was collected between "C at 4mmHg. Ethyl 7-octene decenoate 2b. Synthesized as above with high conversion indicated by GC.
Spectra consistent with structure. LRMS , calcd. HRMS Ethyl 9-decene dodecenoate 2c. Product was a thick oil with consistent GC retention times with what was expected.
Step C: Reduction of ester: Synthesis of 2- 4-pentene heptene-l-ol 3a. In a flamed dry ml three neck round bottom flask equipped with a stir bar and condenser, 9.
This solution was kept under an inert atmosphere and cooled to 0 'C. Some bubbling was observed during this addition. The reaction was allowed to warm to room temperature and stirred for 2 hours. The reaction was then slowly quenched with water followed by 3M HC1. The solution was extracted with ether dried over MgSO4 and rotary evaporated.
A clear oil was recovered and vacuum distilled at "C at 1mm Hg. IR CDCl3, cm-1 : Synthesized as above with high conversion by GC. Short path vacuum distillation was done for purification with the main fraction collected at 'C at lmmHg.
Spectral analysis: 1H NMR 1. Due to the size, and therefore the boiling point, of this product a high vacuum short path distillation was done using a short path high vacuum distillation apparatus equipped with a dry ice isopropanol condenser.
The solution was then slowly heated until condensing was observed. The zinc dicarboxylate components aggregated into a self-assembled structures adopting a cubic crystalline lattice, an unprecedented observation for ionomers having a purely hydrocarbon backbone [ 58 ]. Precision ethylene—vinyl halide copolymers have also been examined [ 59 ]. Contrary to many other systems, it was discovered that regardless of the halide identity except iodide and appearance frequency on the polymer backbone, the halogen atoms were included in the unit cell.
This yielded an orthorhombic system in the case of fluorine, and triclinic systems in the case of the larger chlorine and bromine substituents. Motivated by the recent advances in fuel cell membranes, precision polymers incorporating sulfonic [ 60 ] and phosphonic [ 61 , 62 ] acids have been investigated for potential uses as proton carriers.
As with carboxylic acids, the aforementioned functionalities must be protected prior to polymerization to prevent poisoning of the metathesis catalyst. While ethyl phosphonates could straightforwardly be deprotected post-hydrogenation, the sulfonate analogues have not led to comparable results.
The significant insolubility of the poly ethylene-co-vinylsulfonic acid s promotes premature precipitation of the material and prevents complete deprotection. This problem is currently being addressed by the Wagener group.
With sufficient spacing 20 methylene spacers or greater , the ethylene—vinylphosphonic acid copolymers show a semicrystalline behavior. Amorphous materials are promoted by shorter methylene segments. Finally, among others, ADMET polymerization has been utilized to produce precision materials containing ether [ 63 ], silicon [ 64 ], or amine [ 65 ] moieties.
These materials are often macromonomers used to synthesize larger polymers, and they have many other uses as well. Telechelic oligomers of polybutadiene Fig. ADMET polybutadiene may alternatively be achieved by the polymerization of 1,5-hexadiene. This polymer can then be used to prepare telechelic oligomers by reacting with a suitable olefin. Sometimes the reaction is incomplete, producing telechelic oligomers. Additionally, polybutadiene produced by cationic polymerization can undergo ADMET depolymerization with acrylates to yield ester-terminated telechelics [ 68 ].
This approach was also used to produce a polyamide by depolymerizing polybutadiene with acryloyl chloride and subsequently reacting with 1,6-diaminohexane. Ester-end-capped polyethylene oligomers have been made by ADMET by reacting 1,9-decadiene and 9-decenyl acetate and subsequently hydrogenating the unsaturated units. Telechelic polyacetylenes have been synthesized by ADMET polymerization of 2,4-hexadiene with 1,2-disubstituted olefins [ 69 ].
Polyacetylene oligomers terminated with a variety of end groups, including silanes, alkyl groups, and esters were prepared with this method. These materials could potentially be used in UV- and hydrolysis-resistant polyurethanes. Some molecular weight control was achieved in the resulting telechelics, which had 2. In another report, 1,9-decadiene was polymerized using [Ru]1 with epoxy-containing monoenes [ 71 ]. The resulting telechelic polymer was then reacted with toluene diisocyanate resulting in a copolymer containing oxazolidone linkages.
ADMET has been used to synthesize ester-terminated telechelics with a similar approach [ 72 ]. Conclusion Over the last two decades, ADMET polymerization has been extensively studied as a unique and valuable means to access and synthesize precision polymers. These materials have provided better understanding of structure—property relationships in various systems, as they serve as models for their ill-defined commercial counterparts.
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Macromolecules , 50 7 , Two molar potassium tert-butoxide was prepared in a dry schlenk tube by combining the salt Aldrich with THF distilled from NaK alloy.