Methyl inside reaction temperatures

In this particular experiment, methyl acrylate was reacted with the Pd/Cu/Fe catalyst at 0.9 MPa oxygen pressure at 45 °C. In about 10 min, the inside reaction temperature reached 120 °C, and at this point, oxygen deficiency set in, leading to palladium black formation. Furthermore, product selectivity decreased due to overoxidation and other side reactions. Experiments such as this on a large scale could very easily lead to dangerous runaway situations. 

A 3-necked flesk fitted with e stirrer, thermometer, ges inlet, dropping funnel, and brine-cooled reflux condenser was charged with 53 g (1.1 mol) methyl mercaptan and 0.35 g mercuric methyl mercaptide. After admitting 56 g (1.0 mol) of acrolein during the course of 15 minutes with an inside temperature of about 10°C, the temperature was allowed to rise spontaneously to 75°C, at which point an ice bath was applied. There was no indication of further reaction one hour after the addition of the acrolein. Distillation of the product gave 71 g (yield 68%) of )3-methylmercaptopropionaldehyde, as described in U.S. Patent 2,584,496. 

In the methylation reaction of 33 with methyl iodide in the presence of potassium carbonate, the A-methyl derivative 35 was formed, which epimerized to 34 on standing in CDCI3 solution at room temperature. This epimerization can be rationalized in terms of the favored N-inside conformation 33 with an equatorial aryl group. On A-methylation, the... 

A typical example of frontal polymerization is the polymerization of methyl methacrylate (or an oligomer), placed inside a long aluminum tube 249 these tubes continuously dip into a bath with a liquid heated up to temperature of 70 - 80°C. The part at the tubes above the bath are cooled so that the reactive material does not polymerize. Polymerization shrinkage is compensated by continuous injection of a monomer or oligomer into the reaction zone. The appropriate combination of injection rate, velocity of tube movement through the reaction zone, and tube diameter are chosen according to experimental studies of the process. 

Bein and coworkers investigated the formation of poly(methyl methacrylate) (PMMA) through polymerization of methyl methacrylate (MMA) in channels of microporous crystals including Na-Y, mordenite, zeolite / , and ZSM-5, and mesoporous molecular sieves such as MCM-41 and MCM-48.[83] MMA in zeolites can also polymerize as acrylonitrile does, and with an increase in the host channel size the polymerization degree is enhanced. Electron microscopic observation indicates that the polymerization reaction proceeds mainly inside the zeolite channels, because almost no polymers are observable on the external surface of the zeolite particles. This is further confirmed by the fact that the polymer/zeolite composite lacks the characteristic glass transition temperature for a bulk polymer. 

Ring-opening polymerization reactions of several 2-substituted-2-oxazolines (i.e. 2-methyl, 2-ethyl, 2-nonyl, and 2-phenyl) in the presence of methyl tosylate as catalyst have been described by Schubert et al. (Scheme 14.14) [33-35]. The reactions were performed in the temperature range 80 to 200 °C inside a single-mode micro-wave reactor. In a typical run, 25 mL stock solutions of monomer-initiator-solvent were prepared before the polymerization. These stock solutions were divided among different reaction vials so each experiment was performed on a 1-mL scale. 

The reduction of methyl methacrylate in a PMMA latex was studied. Pulsed electron beam experiments were performed to study the effect of supercritical carbon dioxide on the monomer concentration inside the polymer particles during the polymerization reaction. The partitioning behaviour of methyl methacrylate between water and carbon dioxide was measured as a function of pressure and temperature. 28 refs. 

Nystrom and co-workers (1959) applied the Wilzbach technique to H labeling of methyl esters of saturated fatty acids, and the anticipated substitution of hydrogen by tritium occurred. In this procedure, gram amounts of methyl esters of palmitic and stearic acids were exposed to 1 Ci of H2 at room temperature. The fatty acid esters were deposited as thin layers by solvent evaporation on the inside wall of 1- X 10-inch reaction tubes. Methyl laurate and methyl myristate, being liquid at room temperature, required sealed ampules equipped with break seals the ampules were rotated to provide a continuously renewed thin film during their exposure to 5 Ci of tritium gas. Purification of the tritiated methyl esters includes saponification and extraction of the free acid with diethyl ether. 

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