Methyl iodide methacrylate

Free hydroxyl groups of heparin have been caused to react with methyl iodide, to afford methoxyl derivatives,100,101,264 with chlorosul-fonic acid-pyridine266 or chlorosulfonic-sulfuric acid,267 to give su-persulfated heparins, and with methacryl chloride, to provide a water-soluble, heparin methacrylate268 that can be condensed to heparin polymers. 

Only one kinetic study exists on initiation of methacrylate polymerization by a sodium compound. The initiator was the disodium oligomer ( tetramer ) of a-methylstyrene and polymerization was investigated at 25°C in toluene in presence of 0.05—0.2 mole fraction of tetrahydrofuran [181]. An internal first order disappearance of monomer was observed, the first order coefficient being directly proportional to active chain and tetrahydrofuran concentrations. The rate coefficients evaluated, e.g. fep = 3.1—13 X 10 1 mole sec at various tetrahydrofuran concentrations, are much lower than those for lithium initiators. They were, however, evaluated using a methyl iodide titration technique to estimate the active chain concentration. In view of the reactivity of tritiated acetic acid with many short chains which are clearly not active in chain propagation, there must be suspicion of similar behaviour with methyl iodide. If this happens, the active chain concentration would be over-estimated and the derived fep value would be too low. Unfortunately no molecular weights of the precipitable polymer were determined, so that it is impossible to check on active chain concentration using this alternative method. 

Mercury compounds Methanol Methoxychlor Methyl bromide Methyl chloride Methyl ethyl ketone Methyl hydrazine Methyl iodide Methyl isobutyl ketone Methyl isocyanate Methyl methacrylate Methyl f-butyl ether... 

Polymerization of tetramethylammonium methacrylate was carried out in water at 45 °C in the presence of the water soluble dithiobenzoate RAFT agent 18 and with 2,2 -azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (Wako VA-044) initiator. Methylation of the resultant poly(tetra-methylammonium methacrylate) with excess methyl iodide provided PMMA with Mn 8200, Mw/A/nl.l7 and/nm.-/nr.-rr 2 21 77 compared to poly(methacrylic add) under similar conditions with mm.mrrr 3 34 63 (this is similar to PMMA obtained by bulk polymerization for which mm.mrrr 3 35 62). Polymerization of salts (Na, K, Cs) methacrylic acid with inorganic counterions also gave a more syndiotactic polymer though the effect appears smaller... 

Bromo-3-methyl-4-nitroisothiazole can be converted into the 5-iodo analogue by reaction with sodium iodide in acetone (65AHC(4)107). Halogen exchange also takes place when 4-bromo-3-methylisothiazole-5-diazonium chloride is treated with methyl methacrylate and hydrolyzed, giving the chloro compound (150) (72AHC(14)l). 

Our requirements for certain applications called for the preparation of block copolymers of styrene and alkali metal methacrylates with molecular weights of about 20,000 and methacrylate contents of about 10 mol%. In this report we describe the preparation and reactions of S-b-MM and S-b-tBM. In the course of our investigation, we have found several new methods for the conversion of alkyl methacrylate blocks into methacrylic acid and/or metal methacrylate blocks. Of particular interest is the reaction with trimethylsilyl iodide. Under the same mild conditions, MM blocks are completely unreactive, while tBM blocks are cleanly converted to either methacrylic acid or metal methacrylate blocks. As a consequence of this unexpected selectivity, we also report the preparation of the new block copolymers, poly(methyl methacrylate-b-potassium methacrylate) (MM-b-MA.K) and poly(methyl methacrvlate-b-methacrylic acid) (MM-b-MA). 

Materials. Methyl methacrylate was a product of Rohm and Haas, and t-butyl methacrylate was obtained from Polvsciences, Inc. Potassium trimethylsilanolate (PTMS) was obtained from Petrarch Systems, Inc. Anhydrous lithium iodide, trimethylsilyl iodide (TMSI), and n-butyllit.ium (in hexanes) were purchased from Aldrich Chemical Co. 

In summary, we have examined several new methods for cleaving ester groups in poly(styrene-b-alkyl methacrylates). Short blocks of methyl methacrylate are very difficult to hydrolyze, but can be cleaved with reagents such as lithium iodide and potassium trimethylsilanolate. These latter reagents, however, result in side-reactions which appear to crosslink the polymer. 

In experiments with a supported palladium catalyst, Pd/C, satisfactory yields were obtained without the use of phosphine ligands for the Heck reactions of aryl iodide with acrylonitrile, styrene, and methyl methacrylate in the ionic liquid [BMIM]PF6 (259). The addition of triethylamine improved the yields. The Pd/C remained in the ionic liquid only. The ionic liquid containing Pd/C can be reused as... 

Compound Name Mercuric Chloride Mercuric Iodide Mercuric Chloride Mercuric Ammonium Chloride Mercuric Cyanide Mercuric Cyanide Mercuric Chloride Mercuric Nitrate Mercuric Oxide Mercuric Chloride Mercuric Nitrate Mercurous Chloride Mercurous Nitrate Mercurous Chloride Mesityl Oxide Calcium Resinate Methyl Methacrylate N-Butyl Methacrylate Glycidyl Methacrylate Ethyl Methacrylate Methyl Methacrylate Methallyl Chloride Methallyl Chloride Formaldehyde Solution Methane... 

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